From 2ed5d515997c8c2760f23a819c2c5779df385569 Mon Sep 17 00:00:00 2001
From: amazigh <76942612+aguiddir@users.noreply.github.com>
Date: Fri, 8 Dec 2023 02:05:27 +0100
Subject: [PATCH 1/9] =?UTF-8?q?=E2=9C=A8=20Add=20mypy=20for=20static=20typ?=
 =?UTF-8?q?e=20checking=20and=20type=20annotations=20(#249)?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 datacompy/core.py  | 156 +++++++++++++++++++++++++++------------------
 datacompy/fugue.py |  42 +++++++-----
 datacompy/py.typed |   0
 datacompy/spark.py | 142 ++++++++++++++++++++++-------------------
 pyproject.toml     |  13 ++++
 5 files changed, 211 insertions(+), 142 deletions(-)
 create mode 100644 datacompy/py.typed

diff --git a/datacompy/core.py b/datacompy/core.py
index 9213c0e7..fda507fb 100644
--- a/datacompy/core.py
+++ b/datacompy/core.py
@@ -20,9 +20,9 @@
 PROC COMPARE in SAS - i.e. human-readable reporting on the difference between
 two dataframes.
 """
-
 import logging
 import os
+from typing import cast, Any, List, Dict, Union, Optional
 
 import numpy as np
 import pandas as pd
@@ -79,18 +79,18 @@ class Compare:
 
     def __init__(
         self,
-        df1,
-        df2,
-        join_columns=None,
-        on_index=False,
-        abs_tol=0,
-        rel_tol=0,
-        df1_name="df1",
-        df2_name="df2",
-        ignore_spaces=False,
-        ignore_case=False,
-        cast_column_names_lower=True,
-    ):
+        df1: pd.DataFrame,
+        df2: pd.DataFrame,
+        join_columns: Optional[Union[List[str], str]] = None,
+        on_index: bool = False,
+        abs_tol: float = 0,
+        rel_tol: float = 0,
+        df1_name: str = "df1",
+        df2_name: str = "df2",
+        ignore_spaces: bool = False,
+        ignore_case: bool = False,
+        cast_column_names_lower: bool = True,
+    ) -> None:
         self.cast_column_names_lower = cast_column_names_lower
         if on_index and join_columns is not None:
             raise Exception("Only provide on_index or join_columns")
@@ -107,11 +107,11 @@ def __init__(
         else:
             self.join_columns = [
                 str(col).lower() if self.cast_column_names_lower else str(col)
-                for col in join_columns
+                for col in cast(List[str], join_columns)
             ]
             self.on_index = False
 
-        self._any_dupes = False
+        self._any_dupes: bool = False
         self.df1 = df1
         self.df2 = df2
         self.df1_name = df1_name
@@ -120,16 +120,18 @@ def __init__(
         self.rel_tol = rel_tol
         self.ignore_spaces = ignore_spaces
         self.ignore_case = ignore_case
-        self.df1_unq_rows = self.df2_unq_rows = self.intersect_rows = None
-        self.column_stats = []
-        self._compare(ignore_spaces, ignore_case)
+        self.df1_unq_rows: pd.DataFrame
+        self.df2_unq_rows: pd.DataFrame
+        self.intersect_rows: pd.DataFrame
+        self.column_stats: List[Dict[str, Any]] = []
+        self._compare(ignore_spaces=ignore_spaces, ignore_case=ignore_case)
 
     @property
-    def df1(self):
+    def df1(self) -> pd.DataFrame:
         return self._df1
 
     @df1.setter
-    def df1(self, df1):
+    def df1(self, df1: pd.DataFrame) -> None:
         """Check that it is a dataframe and has the join columns"""
         self._df1 = df1
         self._validate_dataframe(
@@ -137,18 +139,20 @@ def df1(self, df1):
         )
 
     @property
-    def df2(self):
+    def df2(self) -> pd.DataFrame:
         return self._df2
 
     @df2.setter
-    def df2(self, df2):
+    def df2(self, df2: pd.DataFrame) -> None:
         """Check that it is a dataframe and has the join columns"""
         self._df2 = df2
         self._validate_dataframe(
             "df2", cast_column_names_lower=self.cast_column_names_lower
         )
 
-    def _validate_dataframe(self, index, cast_column_names_lower=True):
+    def _validate_dataframe(
+        self, index: str, cast_column_names_lower: bool = True
+    ) -> None:
         """Check that it is a dataframe and has the join columns
 
         Parameters
@@ -163,9 +167,11 @@ def _validate_dataframe(self, index, cast_column_names_lower=True):
             raise TypeError(f"{index} must be a pandas DataFrame")
 
         if cast_column_names_lower:
-            dataframe.columns = [str(col).lower() for col in dataframe.columns]
+            dataframe.columns = pd.Index(
+                [str(col).lower() for col in dataframe.columns]
+            )
         else:
-            dataframe.columns = [str(col) for col in dataframe.columns]
+            dataframe.columns = pd.Index([str(col) for col in dataframe.columns])
         # Check if join_columns are present in the dataframe
         if not set(self.join_columns).issubset(set(dataframe.columns)):
             raise ValueError(f"{index} must have all columns from join_columns")
@@ -182,7 +188,7 @@ def _validate_dataframe(self, index, cast_column_names_lower=True):
             ):
                 self._any_dupes = True
 
-    def _compare(self, ignore_spaces, ignore_case):
+    def _compare(self, ignore_spaces: bool, ignore_case: bool) -> None:
         """Actually run the comparison.  This tries to run df1.equals(df2)
         first so that if they're truly equal we can tell.
 
@@ -214,26 +220,31 @@ def _compare(self, ignore_spaces, ignore_case):
         else:
             LOG.info("df1 does not match df2")
 
-    def df1_unq_columns(self):
+    def df1_unq_columns(self) -> OrderedSet[str]:
         """Get columns that are unique to df1"""
-        return OrderedSet(self.df1.columns) - OrderedSet(self.df2.columns)
+        return cast(
+            OrderedSet[str], OrderedSet(self.df1.columns) - OrderedSet(self.df2.columns)
+        )
 
-    def df2_unq_columns(self):
+    def df2_unq_columns(self) -> OrderedSet[str]:
         """Get columns that are unique to df2"""
-        return OrderedSet(self.df2.columns) - OrderedSet(self.df1.columns)
+        return cast(
+            OrderedSet[str], OrderedSet(self.df2.columns) - OrderedSet(self.df1.columns)
+        )
 
-    def intersect_columns(self):
+    def intersect_columns(self) -> OrderedSet[str]:
         """Get columns that are shared between the two dataframes"""
         return OrderedSet(self.df1.columns) & OrderedSet(self.df2.columns)
 
-    def _dataframe_merge(self, ignore_spaces):
+    def _dataframe_merge(self, ignore_spaces: bool) -> None:
         """Merge df1 to df2 on the join columns, to get df1 - df2, df2 - df1
         and df1 & df2
 
         If ``on_index`` is True, this will join on index values, otherwise it
         will join on the ``join_columns``.
         """
-
+        params: Dict[str, Any]
+        index_column: str
         LOG.debug("Outer joining")
         if self._any_dupes:
             LOG.debug("Duplicate rows found, deduping by order of remaining fields")
@@ -275,11 +286,10 @@ def _dataframe_merge(self, ignore_spaces):
         # Clean up temp columns for duplicate row matching
         if self._any_dupes:
             if self.on_index:
-                outer_join.index = outer_join[index_column]
-                outer_join.drop(index_column, axis=1, inplace=True)
+                outer_join.set_index(keys=index_column, drop=True, inplace=True)
                 self.df1.drop(index_column, axis=1, inplace=True)
                 self.df2.drop(index_column, axis=1, inplace=True)
-            outer_join.drop(order_column, axis=1, inplace=True)
+            outer_join.drop(labels=order_column, axis=1, inplace=True)
             self.df1.drop(order_column, axis=1, inplace=True)
             self.df2.drop(order_column, axis=1, inplace=True)
 
@@ -306,7 +316,7 @@ def _dataframe_merge(self, ignore_spaces):
             f"Number of rows in df1 and df2 (not necessarily equal): {len(self.intersect_rows)}"
         )
 
-    def _intersect_compare(self, ignore_spaces, ignore_case):
+    def _intersect_compare(self, ignore_spaces: bool, ignore_case: bool) -> None:
         """Run the comparison on the intersect dataframe
 
         This loops through all columns that are shared between df1 and df2, and
@@ -319,7 +329,7 @@ def _intersect_compare(self, ignore_spaces, ignore_case):
             if column in self.join_columns:
                 match_cnt = row_cnt
                 col_match = ""
-                max_diff = 0
+                max_diff = 0.0
                 null_diff = 0
             else:
                 col_1 = column + "_df1"
@@ -367,11 +377,11 @@ def _intersect_compare(self, ignore_spaces, ignore_case):
                 }
             )
 
-    def all_columns_match(self):
+    def all_columns_match(self) -> bool:
         """Whether the columns all match in the dataframes"""
         return self.df1_unq_columns() == self.df2_unq_columns() == set()
 
-    def all_rows_overlap(self):
+    def all_rows_overlap(self) -> bool:
         """Whether the rows are all present in both dataframes
 
         Returns
@@ -382,7 +392,7 @@ def all_rows_overlap(self):
         """
         return len(self.df1_unq_rows) == len(self.df2_unq_rows) == 0
 
-    def count_matching_rows(self):
+    def count_matching_rows(self) -> int:
         """Count the number of rows match (on overlapping fields)
 
         Returns
@@ -396,12 +406,12 @@ def count_matching_rows(self):
                 match_columns.append(column + "_match")
         return self.intersect_rows[match_columns].all(axis=1).sum()
 
-    def intersect_rows_match(self):
+    def intersect_rows_match(self) -> bool:
         """Check whether the intersect rows all match"""
         actual_length = self.intersect_rows.shape[0]
         return self.count_matching_rows() == actual_length
 
-    def matches(self, ignore_extra_columns=False):
+    def matches(self, ignore_extra_columns: bool = False) -> bool:
         """Return True or False if the dataframes match.
 
         Parameters
@@ -418,7 +428,7 @@ def matches(self, ignore_extra_columns=False):
         else:
             return True
 
-    def subset(self):
+    def subset(self) -> bool:
         """Return True if dataframe 2 is a subset of dataframe 1.
 
         Dataframe 2 is considered a subset if all of its columns are in
@@ -434,7 +444,9 @@ def subset(self):
         else:
             return True
 
-    def sample_mismatch(self, column, sample_count=10, for_display=False):
+    def sample_mismatch(
+        self, column: str, sample_count: int = 10, for_display: bool = False
+    ) -> pd.DataFrame:
         """Returns a sample sub-dataframe which contains the identifying
         columns, and df1 and df2 versions of the column.
 
@@ -463,13 +475,16 @@ def sample_mismatch(self, column, sample_count=10, for_display=False):
         return_cols = self.join_columns + [column + "_df1", column + "_df2"]
         to_return = sample[return_cols]
         if for_display:
-            to_return.columns = self.join_columns + [
-                column + " (" + self.df1_name + ")",
-                column + " (" + self.df2_name + ")",
-            ]
+            to_return.columns = pd.Index(
+                self.join_columns
+                + [
+                    column + " (" + self.df1_name + ")",
+                    column + " (" + self.df2_name + ")",
+                ]
+            )
         return to_return
 
-    def all_mismatch(self, ignore_matching_cols=False):
+    def all_mismatch(self, ignore_matching_cols: bool = False) -> pd.DataFrame:
         """All rows with any columns that have a mismatch. Returns all df1 and df2 versions of the columns and join
         columns.
 
@@ -512,7 +527,12 @@ def all_mismatch(self, ignore_matching_cols=False):
         mm_bool = self.intersect_rows[match_list].all(axis="columns")
         return self.intersect_rows[~mm_bool][self.join_columns + return_list]
 
-    def report(self, sample_count=10, column_count=10, html_file=None):
+    def report(
+        self,
+        sample_count: int = 10,
+        column_count: int = 10,
+        html_file: Optional[str] = None,
+    ) -> str:
         """Returns a string representation of a report.  The representation can
         then be printed or saved to a file.
 
@@ -533,7 +553,7 @@ def report(self, sample_count=10, column_count=10, html_file=None):
             The report, formatted kinda nicely.
         """
 
-        def df_to_str(pdf):
+        def df_to_str(pdf: pd.DataFrame) -> str:
             if not self.on_index:
                 pdf = pdf.reset_index(drop=True)
             return pdf.to_string()
@@ -674,7 +694,7 @@ def df_to_str(pdf):
         return report
 
 
-def render(filename, *fields):
+def render(filename: str, *fields: Union[int, float, str]) -> str:
     """Renders out an individual template.  This basically just reads in a
     template file, and applies ``.format()`` on the fields.
 
@@ -697,8 +717,13 @@ def render(filename, *fields):
 
 
 def columns_equal(
-    col_1, col_2, rel_tol=0, abs_tol=0, ignore_spaces=False, ignore_case=False
-):
+    col_1: "pd.Series[Any]",
+    col_2: "pd.Series[Any]",
+    rel_tol: float = 0,
+    abs_tol: float = 0,
+    ignore_spaces: bool = False,
+    ignore_case: bool = False,
+) -> "pd.Series[bool]":
     """Compares two columns from a dataframe, returning a True/False series,
     with the same index as column 1.
 
@@ -731,6 +756,7 @@ def columns_equal(
         A series of Boolean values.  True == the values match, False == the
         values don't match.
     """
+    compare: pd.Series[bool]
     try:
         compare = pd.Series(
             np.isclose(col_1, col_2, rtol=rel_tol, atol=abs_tol, equal_nan=True)
@@ -773,7 +799,9 @@ def columns_equal(
     return compare
 
 
-def compare_string_and_date_columns(col_1, col_2):
+def compare_string_and_date_columns(
+    col_1: "pd.Series[Any]", col_2: "pd.Series[Any]"
+) -> "pd.Series[bool]":
     """Compare a string column and date column, value-wise.  This tries to
     convert a string column to a date column and compare that way.
 
@@ -812,7 +840,9 @@ def compare_string_and_date_columns(col_1, col_2):
             return pd.Series(False, index=col_1.index)
 
 
-def get_merged_columns(original_df, merged_df, suffix):
+def get_merged_columns(
+    original_df: pd.DataFrame, merged_df: pd.DataFrame, suffix: str
+) -> List[str]:
     """Gets the columns from an original dataframe, in the new merged dataframe
 
     Parameters
@@ -836,7 +866,7 @@ def get_merged_columns(original_df, merged_df, suffix):
     return columns
 
 
-def temp_column_name(*dataframes):
+def temp_column_name(*dataframes: pd.DataFrame) -> str:
     """Gets a temp column name that isn't included in columns of any dataframes
 
     Parameters
@@ -861,7 +891,7 @@ def temp_column_name(*dataframes):
             return temp_column
 
 
-def calculate_max_diff(col_1, col_2):
+def calculate_max_diff(col_1: "pd.Series[Any]", col_2: "pd.Series[Any]") -> float:
     """Get a maximum difference between two columns
 
     Parameters
@@ -877,12 +907,14 @@ def calculate_max_diff(col_1, col_2):
         Numeric field, or zero.
     """
     try:
-        return (col_1.astype(float) - col_2.astype(float)).abs().max()
+        return cast(float, (col_1.astype(float) - col_2.astype(float)).abs().max())
     except:
-        return 0
+        return 0.0
 
 
-def generate_id_within_group(dataframe, join_columns):
+def generate_id_within_group(
+    dataframe: pd.DataFrame, join_columns: List[str]
+) -> "pd.Series[int]":
     """Generate an ID column that can be used to deduplicate identical rows.  The series generated
     is the order within a unique group, and it handles nulls.
 
diff --git a/datacompy/fugue.py b/datacompy/fugue.py
index 80038aa2..9a0109f4 100644
--- a/datacompy/fugue.py
+++ b/datacompy/fugue.py
@@ -20,7 +20,7 @@
 import logging
 import pickle
 from collections import defaultdict
-from typing import Any, Callable, Dict, Iterable, List, Optional, Tuple, Union
+from typing import Any, Callable, Dict, Iterable, List, cast, Union, Optional, Tuple
 
 import fugue.api as fa
 import pandas as pd
@@ -35,7 +35,7 @@
 HASH_COL = "__datacompy__hash__"
 
 
-def unq_columns(df1: AnyDataFrame, df2: AnyDataFrame):
+def unq_columns(df1: AnyDataFrame, df2: AnyDataFrame) -> OrderedSet[str]:
     """Get columns that are unique to df1
 
     Parameters
@@ -53,10 +53,10 @@ def unq_columns(df1: AnyDataFrame, df2: AnyDataFrame):
     """
     col1 = fa.get_column_names(df1)
     col2 = fa.get_column_names(df2)
-    return OrderedSet(col1) - OrderedSet(col2)
+    return cast(OrderedSet[str], OrderedSet(col1) - OrderedSet(col2))
 
 
-def intersect_columns(df1: AnyDataFrame, df2: AnyDataFrame):
+def intersect_columns(df1: AnyDataFrame, df2: AnyDataFrame) -> OrderedSet[str]:
     """Get columns that are shared between the two dataframes
 
     Parameters
@@ -77,7 +77,7 @@ def intersect_columns(df1: AnyDataFrame, df2: AnyDataFrame):
     return OrderedSet(col1) & OrderedSet(col2)
 
 
-def all_columns_match(df1: AnyDataFrame, df2: AnyDataFrame):
+def all_columns_match(df1: AnyDataFrame, df2: AnyDataFrame) -> bool:
     """Whether the columns all match in the dataframes
 
     Parameters
@@ -302,9 +302,9 @@ def report(
     ignore_spaces: bool = False,
     ignore_case: bool = False,
     cast_column_names_lower: bool = True,
-    sample_count=10,
-    column_count=10,
-    html_file=None,
+    sample_count: int = 10,
+    column_count: int = 10,
+    html_file: Optional[str] = None,
     parallelism: Optional[int] = None,
 ) -> str:
     """Returns a string representation of a report.  The representation can
@@ -320,7 +320,7 @@ def report(
         First dataframe to check
     df2 : ``AnyDataFrame``
         Second dataframe to check
-    join_columns : list or str, optional
+    join_columns : list or str
         Column(s) to join dataframes on.  If a string is passed in, that one
         column will be used.
     abs_tol : float, optional
@@ -406,7 +406,7 @@ def report(
     def shape0(col: str) -> int:
         return sum(x[col][0] for x in res)
 
-    def shape1(col: str) -> int:
+    def shape1(col: str) -> Any:
         return first[col][1]
 
     def _sum(col: str) -> int:
@@ -454,6 +454,8 @@ def _any(col: str) -> int:
         "Yes" if _any("_any_dupes") else "No",
     )
 
+    column_stats: List[Dict[str, Any]]
+    match_sample: List[pd.DataFrame]
     column_stats, match_sample = _aggregate_stats(res, sample_count=sample_count)
     any_mismatch = len(match_sample) > 0
 
@@ -673,7 +675,10 @@ def _deserialize(
     ) -> pd.DataFrame:
         arr = [pickle.loads(r["data"]) for r in df if r["left"] == left]
         if len(arr) > 0:
-            return pd.concat(arr).sort_values(schema.names).reset_index(drop=True)
+            return cast(
+                pd.DataFrame,
+                pd.concat(arr).sort_values(schema.names).reset_index(drop=True),
+            )
         # The following is how to construct an empty pandas dataframe with
         # the correct schema, it avoids pandas schema inference which is wrong.
         # This is not needed when upgrading to Fugue >= 0.8.7
@@ -772,7 +777,7 @@ def _get_compare_result(
 
 
 def _aggregate_stats(
-    compares, sample_count
+    compares: List[Any], sample_count: int
 ) -> Tuple[List[Dict[str, Any]], List[pd.DataFrame]]:
     samples = defaultdict(list)
     stats = []
@@ -798,9 +803,16 @@ def _aggregate_stats(
         )
         .reset_index(drop=False)
     )
-    return df.to_dict(orient="records"), [
-        _sample(pd.concat(v), sample_count=sample_count) for v in samples.values()
-    ]
+    return cast(
+        Tuple[List[Dict[str, Any]], List[pd.DataFrame]],
+        (
+            df.to_dict(orient="records"),
+            [
+                _sample(pd.concat(v), sample_count=sample_count)
+                for v in samples.values()
+            ],
+        ),
+    )
 
 
 def _sample(df: pd.DataFrame, sample_count: int) -> pd.DataFrame:
diff --git a/datacompy/py.typed b/datacompy/py.typed
new file mode 100644
index 00000000..e69de29b
diff --git a/datacompy/spark.py b/datacompy/spark.py
index a285036b..53599bd0 100644
--- a/datacompy/spark.py
+++ b/datacompy/spark.py
@@ -13,12 +13,13 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-
 import sys
 from enum import Enum
 from itertools import chain
+from typing import Any, TextIO, List, Union, Tuple, Optional, Dict, Set
 
 try:
+    import pyspark
     from pyspark.sql import functions as F
 except ImportError:
     pass  # Let non-Spark people at least enjoy the loveliness of the pandas datacompy functionality
@@ -29,9 +30,9 @@ class MatchType(Enum):
 
 
 # Used for checking equality with decimal(X, Y) types. Otherwise treated as the string "decimal".
-def decimal_comparator():
+def decimal_comparator() -> str:
     class DecimalComparator(str):
-        def __eq__(self, other):
+        def __eq__(self, other: str) -> bool:  # type: ignore[override]
             return len(other) >= 7 and other[0:7] == "decimal"
 
     return DecimalComparator("decimal")
@@ -48,7 +49,7 @@ def __eq__(self, other):
 ]
 
 
-def _is_comparable(type1, type2):
+def _is_comparable(type1: str, type2: str) -> bool:
     """Checks if two Spark data types can be safely compared.
     Two data types are considered comparable if any of the following apply:
         1. Both data types are the same
@@ -141,17 +142,17 @@ class SparkCompare:
 
     def __init__(
         self,
-        spark_session,
-        base_df,
-        compare_df,
-        join_columns,
-        column_mapping=None,
-        cache_intermediates=False,
-        known_differences=None,
-        rel_tol=0,
-        abs_tol=0,
-        show_all_columns=False,
-        match_rates=False,
+        spark_session: "pyspark.sql.SparkSession",
+        base_df: "pyspark.sql.DataFrame",
+        compare_df: "pyspark.sql.DataFrame",
+        join_columns: List[Union[str, Tuple[str, str]]],
+        column_mapping: Optional[List[Tuple[str, str]]] = None,
+        cache_intermediates: bool = False,
+        known_differences: Optional[List[Dict[str, Any]]] = None,
+        rel_tol: float = 0,
+        abs_tol: float = 0,
+        show_all_columns: bool = False,
+        match_rates: bool = False,
     ):
         self.rel_tol = rel_tol
         self.abs_tol = abs_tol
@@ -164,7 +165,7 @@ def __init__(
         self._original_compare_df = compare_df
         self.cache_intermediates = cache_intermediates
 
-        self.join_columns = self._tuplizer(join_columns)
+        self.join_columns = self._tuplizer(input_list=join_columns)
         self._join_column_names = [name[0] for name in self.join_columns]
 
         self._known_differences = known_differences
@@ -182,13 +183,15 @@ def __init__(
 
         self.spark = spark_session
         self.base_unq_rows = self.compare_unq_rows = None
-        self._base_row_count = self._compare_row_count = self._common_row_count = None
-        self._joined_dataframe = None
-        self._rows_only_base = None
-        self._rows_only_compare = None
-        self._all_matched_rows = None
-        self._all_rows_mismatched = None
-        self.columns_match_dict = {}
+        self._base_row_count: Optional[int] = None
+        self._compare_row_count: Optional[int] = None
+        self._common_row_count: Optional[int] = None
+        self._joined_dataframe: Optional["pyspark.sql.DataFrame"] = None
+        self._rows_only_base: Optional["pyspark.sql.DataFrame"] = None
+        self._rows_only_compare: Optional["pyspark.sql.DataFrame"] = None
+        self._all_matched_rows: Optional["pyspark.sql.DataFrame"] = None
+        self._all_rows_mismatched: Optional["pyspark.sql.DataFrame"] = None
+        self.columns_match_dict: Dict[str, Any] = {}
 
         # drop the duplicates before actual comparison made.
         self.base_df = base_df.dropDuplicates(self._join_column_names)
@@ -200,8 +203,10 @@ def __init__(
             self.compare_df.cache()
             self._compare_row_count = self.compare_df.count()
 
-    def _tuplizer(self, input_list):
-        join_columns = []
+    def _tuplizer(
+        self, input_list: List[Union[str, Tuple[str, str]]]
+    ) -> List[Tuple[str, str]]:
+        join_columns: List[Tuple[str, str]] = []
         for val in input_list:
             if isinstance(val, str):
                 join_columns.append((val, val))
@@ -211,12 +216,12 @@ def _tuplizer(self, input_list):
         return join_columns
 
     @property
-    def columns_in_both(self):
+    def columns_in_both(self) -> Set[str]:
         """set[str]: Get columns in both dataframes"""
         return set(self.base_df.columns) & set(self.compare_df.columns)
 
     @property
-    def columns_compared(self):
+    def columns_compared(self) -> List[str]:
         """list[str]: Get columns to be compared in both dataframes (all
         columns in both excluding the join key(s)"""
         return [
@@ -226,17 +231,17 @@ def columns_compared(self):
         ]
 
     @property
-    def columns_only_base(self):
+    def columns_only_base(self) -> Set[str]:
         """set[str]: Get columns that are unique to the base dataframe"""
         return set(self.base_df.columns) - set(self.compare_df.columns)
 
     @property
-    def columns_only_compare(self):
+    def columns_only_compare(self) -> Set[str]:
         """set[str]: Get columns that are unique to the compare dataframe"""
         return set(self.compare_df.columns) - set(self.base_df.columns)
 
     @property
-    def base_row_count(self):
+    def base_row_count(self) -> int:
         """int: Get the count of rows in the de-duped base dataframe"""
         if self._base_row_count is None:
             self._base_row_count = self.base_df.count()
@@ -244,7 +249,7 @@ def base_row_count(self):
         return self._base_row_count
 
     @property
-    def compare_row_count(self):
+    def compare_row_count(self) -> int:
         """int: Get the count of rows in the de-duped compare dataframe"""
         if self._compare_row_count is None:
             self._compare_row_count = self.compare_df.count()
@@ -252,7 +257,7 @@ def compare_row_count(self):
         return self._compare_row_count
 
     @property
-    def common_row_count(self):
+    def common_row_count(self) -> int:
         """int: Get the count of rows in common between base and compare dataframes"""
         if self._common_row_count is None:
             common_rows = self._get_or_create_joined_dataframe()
@@ -260,19 +265,19 @@ def common_row_count(self):
 
         return self._common_row_count
 
-    def _get_unq_base_rows(self):
+    def _get_unq_base_rows(self) -> "pyspark.sql.DataFrame":
         """Get the rows only from base data frame"""
         return self.base_df.select(self._join_column_names).subtract(
             self.compare_df.select(self._join_column_names)
         )
 
-    def _get_compare_rows(self):
+    def _get_compare_rows(self) -> "pyspark.sql.DataFrame":
         """Get the rows only from compare data frame"""
         return self.compare_df.select(self._join_column_names).subtract(
             self.base_df.select(self._join_column_names)
         )
 
-    def _print_columns_summary(self, myfile):
+    def _print_columns_summary(self, myfile: TextIO) -> None:
         """Prints the column summary details"""
         print("\n****** Column Summary ******", file=myfile)
         print(
@@ -292,7 +297,7 @@ def _print_columns_summary(self, myfile):
             file=myfile,
         )
 
-    def _print_only_columns(self, base_or_compare, myfile):
+    def _print_only_columns(self, base_or_compare: str, myfile: TextIO) -> None:
         """Prints the columns and data types only in either the base or compare datasets"""
 
         if base_or_compare.upper() == "BASE":
@@ -321,7 +326,7 @@ def _print_only_columns(self, base_or_compare, myfile):
             col_type = df.select(column).dtypes[0][1]
             print((format_pattern + "  {:13s}").format(column, col_type), file=myfile)
 
-    def _columns_with_matching_schema(self):
+    def _columns_with_matching_schema(self) -> Dict[str, str]:
         """This function will identify the columns which has matching schema"""
         col_schema_match = {}
         base_columns_dict = dict(self.base_df.dtypes)
@@ -329,12 +334,13 @@ def _columns_with_matching_schema(self):
 
         for base_row, base_type in base_columns_dict.items():
             if base_row in compare_columns_dict:
-                if base_type in compare_columns_dict.get(base_row):
-                    col_schema_match[base_row] = compare_columns_dict.get(base_row)
+                compare_column_type = compare_columns_dict.get(base_row)
+                if compare_column_type is not None and base_type in compare_column_type:
+                    col_schema_match[base_row] = compare_column_type
 
         return col_schema_match
 
-    def _columns_with_schemadiff(self):
+    def _columns_with_schemadiff(self) -> Dict[str, Dict[str, str]]:
         """This function will identify the columns which has different schema"""
         col_schema_diff = {}
         base_columns_dict = dict(self.base_df.dtypes)
@@ -342,15 +348,19 @@ def _columns_with_schemadiff(self):
 
         for base_row, base_type in base_columns_dict.items():
             if base_row in compare_columns_dict:
-                if base_type not in compare_columns_dict.get(base_row):
+                compare_column_type = compare_columns_dict.get(base_row)
+                if (
+                    compare_column_type is not None
+                    and base_type not in compare_column_type
+                ):
                     col_schema_diff[base_row] = dict(
                         base_type=base_type,
-                        compare_type=compare_columns_dict.get(base_row),
+                        compare_type=compare_column_type,
                     )
         return col_schema_diff
 
     @property
-    def rows_both_mismatch(self):
+    def rows_both_mismatch(self) -> Optional["pyspark.sql.DataFrame"]:
         """pyspark.sql.DataFrame: Returns all rows in both dataframes that have mismatches"""
         if self._all_rows_mismatched is None:
             self._merge_dataframes()
@@ -358,7 +368,7 @@ def rows_both_mismatch(self):
         return self._all_rows_mismatched
 
     @property
-    def rows_both_all(self):
+    def rows_both_all(self) -> Optional["pyspark.sql.DataFrame"]:
         """pyspark.sql.DataFrame: Returns all rows in both dataframes"""
         if self._all_matched_rows is None:
             self._merge_dataframes()
@@ -366,7 +376,7 @@ def rows_both_all(self):
         return self._all_matched_rows
 
     @property
-    def rows_only_base(self):
+    def rows_only_base(self) -> "pyspark.sql.DataFrame":
         """pyspark.sql.DataFrame: Returns rows only in the base dataframe"""
         if not self._rows_only_base:
             base_rows = self._get_unq_base_rows()
@@ -386,7 +396,7 @@ def rows_only_base(self):
         return self._rows_only_base
 
     @property
-    def rows_only_compare(self):
+    def rows_only_compare(self) -> Optional["pyspark.sql.DataFrame"]:
         """pyspark.sql.DataFrame: Returns rows only in the compare dataframe"""
         if not self._rows_only_compare:
             compare_rows = self._get_compare_rows()
@@ -407,7 +417,7 @@ def rows_only_compare(self):
 
         return self._rows_only_compare
 
-    def _generate_select_statement(self, match_data=True):
+    def _generate_select_statement(self, match_data: bool = True) -> str:
         """This function is to generate the select statement to be used later in the query."""
         base_only = list(set(self.base_df.columns) - set(self.compare_df.columns))
         compare_only = list(set(self.compare_df.columns) - set(self.base_df.columns))
@@ -440,7 +450,7 @@ def _generate_select_statement(self, match_data=True):
 
         return select_statement
 
-    def _merge_dataframes(self):
+    def _merge_dataframes(self) -> None:
         """Merges the two dataframes and creates self._all_matched_rows and self._all_rows_mismatched."""
         full_joined_dataframe = self._get_or_create_joined_dataframe()
         full_joined_dataframe.createOrReplaceTempView("full_matched_table")
@@ -449,9 +459,8 @@ def _merge_dataframes(self):
         select_query = """SELECT {} FROM full_matched_table A""".format(
             select_statement
         )
-
         self._all_matched_rows = self.spark.sql(select_query).orderBy(
-            self._join_column_names
+            self._join_column_names  # type: ignore[arg-type]
         )
         self._all_matched_rows.createOrReplaceTempView("matched_table")
 
@@ -460,10 +469,10 @@ def _merge_dataframes(self):
         )
         mismatch_query = """SELECT * FROM matched_table A WHERE {}""".format(where_cond)
         self._all_rows_mismatched = self.spark.sql(mismatch_query).orderBy(
-            self._join_column_names
+            self._join_column_names  # type: ignore[arg-type]
         )
 
-    def _get_or_create_joined_dataframe(self):
+    def _get_or_create_joined_dataframe(self) -> "pyspark.sql.DataFrame":
         if self._joined_dataframe is None:
             join_condition = " AND ".join(
                 ["A." + name + "<=>B." + name for name in self._join_column_names]
@@ -488,7 +497,7 @@ def _get_or_create_joined_dataframe(self):
 
         return self._joined_dataframe
 
-    def _print_num_of_rows_with_column_equality(self, myfile):
+    def _print_num_of_rows_with_column_equality(self, myfile: TextIO) -> None:
         # match_dataframe contains columns from both dataframes with flag to indicate if columns matched
         match_dataframe = self._get_or_create_joined_dataframe().select(
             *self.columns_compared
@@ -507,7 +516,10 @@ def _print_num_of_rows_with_column_equality(self, myfile):
             )
         )
         all_rows_matched = self.spark.sql(match_query)
-        matched_rows = all_rows_matched.head()[0]
+        all_rows_matched_head = all_rows_matched.head()
+        matched_rows = (
+            all_rows_matched_head[0] if all_rows_matched_head is not None else 0
+        )
 
         print("\n****** Row Comparison ******", file=myfile)
         print(
@@ -516,7 +528,7 @@ def _print_num_of_rows_with_column_equality(self, myfile):
         )
         print(f"Number of rows with all columns equal: {matched_rows}", file=myfile)
 
-    def _populate_columns_match_dict(self):
+    def _populate_columns_match_dict(self) -> None:
         """
         side effects:
             columns_match_dict assigned to { column -> match_type_counts }
@@ -531,7 +543,7 @@ def _populate_columns_match_dict(self):
             *self.columns_compared
         )
 
-        def helper(c):
+        def helper(c: str) -> "pyspark.sql.Column":
             # Create a predicate for each match type, comparing column values to the match type value
             predicates = [F.col(c) == k.value for k in MatchType]
             # Create a tuple(number of match types found for each match type in this column)
@@ -541,15 +553,15 @@ def helper(c):
 
         # For each column, create a single tuple. This tuple's values correspond to the number of times
         # each match type appears in that column
-        match_data = match_dataframe.agg(
+        match_data_agg = match_dataframe.agg(
             *[helper(col) for col in self.columns_compared]
         ).collect()
-        match_data = match_data[0]
+        match_data = match_data_agg[0]
 
         for c in self.columns_compared:
             self.columns_match_dict[c] = match_data[c]
 
-    def _create_select_statement(self, name):
+    def _create_select_statement(self, name: str) -> str:
         if self._known_differences:
             match_type_comparison = ""
             for k in MatchType:
@@ -568,7 +580,7 @@ def _create_select_statement(self, name):
                 name=name, match_failure=MatchType.MISMATCH.value
             )
 
-    def _create_case_statement(self, name):
+    def _create_case_statement(self, name: str) -> str:
         equal_comparisons = ["(A.{name} IS NULL AND B.{name} IS NULL)"]
         known_diff_comparisons = ["(FALSE)"]
 
@@ -622,7 +634,7 @@ def _create_case_statement(self, name):
             match_failure=MatchType.MISMATCH.value,
         )
 
-    def _print_row_summary(self, myfile):
+    def _print_row_summary(self, myfile: TextIO) -> None:
         base_df_cnt = self.base_df.count()
         compare_df_cnt = self.compare_df.count()
         base_df_with_dup_cnt = self._original_base_df.count()
@@ -647,7 +659,7 @@ def _print_row_summary(self, myfile):
             file=myfile,
         )
 
-    def _print_schema_diff_details(self, myfile):
+    def _print_schema_diff_details(self, myfile: TextIO) -> None:
         schema_diff_dict = self._columns_with_schemadiff()
 
         if not schema_diff_dict:  # If there are no differences, don't print the section
@@ -691,7 +703,7 @@ def _print_schema_diff_details(self, myfile):
                 file=myfile,
             )
 
-    def _base_to_compare_name(self, base_name):
+    def _base_to_compare_name(self, base_name: str) -> str:
         """Translates a column name in the base dataframe to its counterpart in the
         compare dataframe, if they are different."""
 
@@ -703,7 +715,7 @@ def _base_to_compare_name(self, base_name):
                     return name[1]
             return base_name
 
-    def _print_row_matches_by_column(self, myfile):
+    def _print_row_matches_by_column(self, myfile: TextIO) -> None:
         self._populate_columns_match_dict()
         columns_with_mismatches = {
             key: self.columns_match_dict[key]
@@ -852,7 +864,7 @@ def _print_row_matches_by_column(self, myfile):
                 print(format_pattern.format(*output_row), file=myfile)
 
     # noinspection PyUnresolvedReferences
-    def report(self, file=sys.stdout):
+    def report(self, file: TextIO = sys.stdout) -> None:
         """Creates a comparison report and prints it to the file specified
         (stdout by default).
 
diff --git a/pyproject.toml b/pyproject.toml
index ae11c20c..415849a3 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -74,6 +74,8 @@ qa = [
     "pre-commit",
     "black",
     "isort",
+    "mypy",
+    "pandas-stubs",
 ]
 build = [
     "build",
@@ -102,6 +104,17 @@ use_parentheses = true
 line_length = 88
 profile = "black"
 
+[tool.mypy]
+strict = true
+
+[[tool.mypy.overrides]]
+module = ["fugue.*","triad.*"]
+implicit_reexport = true
+
+[[tool.mypy.overrides]]
+module = "pyarrow"
+ignore_missing_imports = true
+
 [edgetest.envs.core]
 python_version = "3.9"
 conda_install = ["openjdk=8"]

From f57faad2506877947f8c489c3e849107c28ed908 Mon Sep 17 00:00:00 2001
From: Jacob Dawang <jdawang@users.noreply.github.com>
Date: Fri, 8 Dec 2023 09:22:32 -0500
Subject: [PATCH 2/9] Test with and without spark (#252)

* Test without spark

* Bump setup python version

* Separate tests out

* Install datacompy step

* Drop 3.0 and add 3.5

* Add fugue no spark

* Add permissions

* Format and docstrings
---
 .github/workflows/test-package.yml     |  77 ++-
 pyproject.toml                         |  12 +-
 tests/test_fugue.py                    | 672 -------------------------
 tests/test_fugue/conftest.py           |  89 ++++
 tests/test_fugue/test_duckdb.py        | 140 ++++++
 tests/test_fugue/test_fugue_helpers.py |  22 +
 tests/test_fugue/test_fugue_pandas.py  | 194 +++++++
 tests/test_fugue/test_fugue_polars.py  | 124 +++++
 tests/test_fugue/test_fugue_spark.py   | 202 ++++++++
 tests/test_spark.py                    |   3 +
 10 files changed, 851 insertions(+), 684 deletions(-)
 delete mode 100644 tests/test_fugue.py
 create mode 100644 tests/test_fugue/conftest.py
 create mode 100644 tests/test_fugue/test_duckdb.py
 create mode 100644 tests/test_fugue/test_fugue_helpers.py
 create mode 100644 tests/test_fugue/test_fugue_pandas.py
 create mode 100644 tests/test_fugue/test_fugue_polars.py
 create mode 100644 tests/test_fugue/test_fugue_spark.py

diff --git a/.github/workflows/test-package.yml b/.github/workflows/test-package.yml
index 1e4536b3..b5ec2ea2 100644
--- a/.github/workflows/test-package.yml
+++ b/.github/workflows/test-package.yml
@@ -9,39 +9,94 @@ on:
   pull_request:
     branches: [develop, main]
 
+permissions:
+  contents: read
+
 jobs:
-  build:
+  test-dev-install:
 
-    runs-on: ubuntu-latest 
+    runs-on: ubuntu-latest
     strategy:
       fail-fast: false
       matrix:
         python-version: [3.8, 3.9, '3.10']
-        spark-version: [3.0.3, 3.1.3, 3.2.3, 3.3.1, 3.4.0]
+        spark-version: [3.1.3, 3.2.3, 3.3.1, 3.4.0, 3.5.0]
     env:
-      PYTHON_VERSION: ${{ matrix.python-version }} 
+      PYTHON_VERSION: ${{ matrix.python-version }}
       SPARK_VERSION: ${{ matrix.spark-version }}
 
     steps:
-    - uses: actions/checkout@v2
-      
+    - uses: actions/checkout@v3
+
     - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v2
+      uses: actions/setup-python@v5
       with:
         python-version: ${{ matrix.python-version }}
-    
+
     - name: Setup Java JDK
       uses: actions/setup-java@v3
       with:
         java-version: '8'
         distribution: 'adopt'
-        
-    - name: Install Spark
+
+    - name: Install Spark and datacompy
       run: |
         python -m pip install --upgrade pip
         python -m pip install pytest pytest-spark pypandoc
         python -m pip install pyspark==${{ matrix.spark-version }}
-        python -m pip install .[dev,spark]
+        python -m pip install .[dev]
+    - name: Test with pytest
+      run: |
+        python -m pytest tests/
+
+  test-bare-install:
+
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        python-version: [3.8, 3.9, '3.10']
+    env:
+      PYTHON_VERSION: ${{ matrix.python-version }}
+
+    steps:
+    - uses: actions/checkout@v3
+
+    - name: Set up Python ${{ matrix.python-version }}
+      uses: actions/setup-python@v5
+      with:
+        python-version: ${{ matrix.python-version }}
+
+    - name: Install datacompy
+      run: |
+        python -m pip install --upgrade pip
+        python -m pip install .[tests]
+    - name: Test with pytest
+      run: |
+        python -m pytest tests/
+
+  test-fugue-install-no-spark:
+
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        python-version: [3.8, 3.9, '3.10']
+    env:
+      PYTHON_VERSION: ${{ matrix.python-version }}
+
+    steps:
+    - uses: actions/checkout@v3
+
+    - name: Set up Python ${{ matrix.python-version }}
+      uses: actions/setup-python@v5
+      with:
+        python-version: ${{ matrix.python-version }}
+
+    - name: Install datacompy
+      run: |
+        python -m pip install --upgrade pip
+        python -m pip install .[tests,duckdb,polars,dask,ray]
     - name: Test with pytest
       run: |
         python -m pytest tests/
diff --git a/pyproject.toml b/pyproject.toml
index 415849a3..21bcefd1 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -39,6 +39,10 @@ Repository = "https://github.com/capitalone/datacompy.git"
 "Bug Tracker" = "https://github.com/capitalone/datacompy/issues"
 "Source Code" = "https://github.com/capitalone/datacompy"
 
+[build-system]
+requires = ["setuptools>=64.0.0"]
+build-backend = "setuptools.build_meta"
+
 [tool.setuptools]
 packages = ["datacompy"]
 zip-safe = false
@@ -67,8 +71,13 @@ docs = [
 tests = [
     "pytest",
     "pytest-cov",
+]
+
+tests-spark = [
+    "pytest",
+    "pytest-cov",
     "pytest-spark",
-    "fugue[polars,duckdb,spark]",
+    "fugue[spark]",
 ]
 qa = [
     "pre-commit",
@@ -92,6 +101,7 @@ dev = [
     "datacompy[spark]",
     "datacompy[docs]",
     "datacompy[tests]",
+    "datacompy[tests-spark]",
     "datacompy[qa]",
     "datacompy[build]",
 ]
diff --git a/tests/test_fugue.py b/tests/test_fugue.py
deleted file mode 100644
index 47f7008b..00000000
--- a/tests/test_fugue.py
+++ /dev/null
@@ -1,672 +0,0 @@
-#
-# Copyright 2023 Capital One Services, LLC
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-"""
-Testing out the fugue is_match functionality
-"""
-from io import StringIO
-
-import duckdb
-import numpy as np
-import pandas as pd
-import polars as pl
-import pytest
-from ordered_set import OrderedSet
-from pytest import raises
-
-from datacompy import (
-    Compare,
-    all_columns_match,
-    all_rows_overlap,
-    intersect_columns,
-    is_match,
-    report,
-    unq_columns,
-)
-
-
-@pytest.fixture
-def ref_df():
-    np.random.seed(0)
-
-    df1 = pd.DataFrame(
-        dict(
-            a=np.random.randint(0, 10, 100),
-            b=np.random.rand(100),
-            c=np.random.choice(["aaa", "b_c", "csd"], 100),
-        )
-    )
-    df1_copy = df1.copy()
-    df2 = df1.copy().drop(columns=["c"])
-    df3 = df1.copy().drop(columns=["a", "b"])
-    df4 = pd.DataFrame(
-        dict(
-            a=np.random.randint(1, 12, 100),  # shift the join col
-            b=np.random.rand(100),
-            c=np.random.choice(["aaa", "b_c", "csd"], 100),
-        )
-    )
-    return [df1, df1_copy, df2, df3, df4]
-
-
-@pytest.fixture
-def shuffle_df(ref_df):
-    return ref_df[0].sample(frac=1.0)
-
-
-@pytest.fixture
-def float_off_df(shuffle_df):
-    return shuffle_df.assign(b=shuffle_df.b + 0.0001)
-
-
-@pytest.fixture
-def upper_case_df(shuffle_df):
-    return shuffle_df.assign(c=shuffle_df.c.str.upper())
-
-
-@pytest.fixture
-def space_df(shuffle_df):
-    return shuffle_df.assign(c=shuffle_df.c + " ")
-
-
-@pytest.fixture
-def upper_col_df(shuffle_df):
-    return shuffle_df.rename(columns={"a": "A"})
-
-
-@pytest.fixture
-def simple_diff_df1():
-    return pd.DataFrame(dict(aa=[0, 1, 0], bb=[2.1, 3.1, 4.1])).convert_dtypes()
-
-
-@pytest.fixture
-def simple_diff_df2():
-    return pd.DataFrame(
-        dict(aa=[1, 0, 1], bb=[3.1, 4.1, 5.1], cc=["a", "b", "c"])
-    ).convert_dtypes()
-
-
-@pytest.fixture
-def no_intersection_diff_df1():
-    np.random.seed(0)
-    return pd.DataFrame(dict(x=["a"], y=[0.1])).convert_dtypes()
-
-
-@pytest.fixture
-def no_intersection_diff_df2():
-    return pd.DataFrame(dict(x=["b"], y=[1.1])).convert_dtypes()
-
-
-@pytest.fixture
-def large_diff_df1():
-    np.random.seed(0)
-    data = np.random.randint(0, 7, size=10000)
-    return pd.DataFrame({"x": data, "y": np.array([9] * 10000)}).convert_dtypes()
-
-
-@pytest.fixture
-def large_diff_df2():
-    np.random.seed(0)
-    data = np.random.randint(6, 11, size=10000)
-    return pd.DataFrame({"x": data, "y": np.array([9] * 10000)}).convert_dtypes()
-
-
-def test_is_match_native(
-    ref_df,
-    shuffle_df,
-    float_off_df,
-    upper_case_df,
-    space_df,
-    upper_col_df,
-):
-    # defaults to Compare class
-    assert is_match(ref_df[0], ref_df[0].copy(), join_columns="a")
-    assert not is_match(ref_df[0], shuffle_df, join_columns="a")
-    # Fugue
-    assert is_match(ref_df[0], shuffle_df, join_columns="a", parallelism=2)
-
-    assert not is_match(ref_df[0], float_off_df, join_columns="a", parallelism=2)
-    assert not is_match(
-        ref_df[0], float_off_df, abs_tol=0.00001, join_columns="a", parallelism=2
-    )
-    assert is_match(
-        ref_df[0], float_off_df, abs_tol=0.001, join_columns="a", parallelism=2
-    )
-    assert is_match(
-        ref_df[0], float_off_df, abs_tol=0.001, join_columns="a", parallelism=2
-    )
-
-    assert not is_match(ref_df[0], upper_case_df, join_columns="a", parallelism=2)
-    assert is_match(
-        ref_df[0], upper_case_df, join_columns="a", ignore_case=True, parallelism=2
-    )
-
-    assert not is_match(ref_df[0], space_df, join_columns="a", parallelism=2)
-    assert is_match(
-        ref_df[0], space_df, join_columns="a", ignore_spaces=True, parallelism=2
-    )
-
-    assert is_match(ref_df[0], upper_col_df, join_columns="a", parallelism=2)
-
-    with raises(AssertionError):
-        is_match(
-            ref_df[0],
-            upper_col_df,
-            join_columns="a",
-            cast_column_names_lower=False,
-            parallelism=2,
-        )
-
-
-def test_is_match_spark(
-    spark_session,
-    ref_df,
-    shuffle_df,
-    float_off_df,
-    upper_case_df,
-    space_df,
-    upper_col_df,
-):
-    ref_df[0].iteritems = ref_df[0].items  # pandas 2 compatibility
-    rdf = spark_session.createDataFrame(ref_df[0])
-
-    assert is_match(rdf, shuffle_df, join_columns="a")
-
-    assert not is_match(rdf, float_off_df, join_columns="a")
-    assert not is_match(rdf, float_off_df, abs_tol=0.00001, join_columns="a")
-    assert is_match(rdf, float_off_df, abs_tol=0.001, join_columns="a")
-    assert is_match(rdf, float_off_df, abs_tol=0.001, join_columns="a")
-
-    assert not is_match(rdf, upper_case_df, join_columns="a")
-    assert is_match(rdf, upper_case_df, join_columns="a", ignore_case=True)
-
-    assert not is_match(rdf, space_df, join_columns="a")
-    assert is_match(rdf, space_df, join_columns="a", ignore_spaces=True)
-
-    assert is_match(rdf, upper_col_df, join_columns="a")
-
-    with raises(AssertionError):
-        is_match(rdf, upper_col_df, join_columns="a", cast_column_names_lower=False)
-
-    assert is_match(
-        spark_session.sql("SELECT 'a' AS a, 'b' AS b"),
-        spark_session.sql("SELECT 'a' AS a, 'b' AS b"),
-        join_columns="a",
-    )
-
-
-def test_is_match_polars(
-    ref_df,
-    shuffle_df,
-    float_off_df,
-    upper_case_df,
-    space_df,
-    upper_col_df,
-):
-    rdf = pl.from_pandas(ref_df[0])
-
-    assert is_match(rdf, shuffle_df, join_columns="a")
-
-    assert not is_match(rdf, float_off_df, join_columns="a")
-    assert not is_match(rdf, float_off_df, abs_tol=0.00001, join_columns="a")
-    assert is_match(rdf, float_off_df, abs_tol=0.001, join_columns="a")
-    assert is_match(rdf, float_off_df, abs_tol=0.001, join_columns="a")
-
-    assert not is_match(rdf, upper_case_df, join_columns="a")
-    assert is_match(rdf, upper_case_df, join_columns="a", ignore_case=True)
-
-    assert not is_match(rdf, space_df, join_columns="a")
-    assert is_match(rdf, space_df, join_columns="a", ignore_spaces=True)
-
-    assert is_match(rdf, upper_col_df, join_columns="a")
-    with raises(AssertionError):
-        is_match(rdf, upper_col_df, join_columns="a", cast_column_names_lower=False)
-
-
-def test_is_match_duckdb(
-    ref_df,
-    shuffle_df,
-    float_off_df,
-    upper_case_df,
-    space_df,
-    upper_col_df,
-):
-    with duckdb.connect():
-        rdf = duckdb.from_df(ref_df[0])
-
-        assert is_match(rdf, shuffle_df, join_columns="a")
-
-        assert not is_match(rdf, float_off_df, join_columns="a")
-        assert not is_match(rdf, float_off_df, abs_tol=0.00001, join_columns="a")
-        assert is_match(rdf, float_off_df, abs_tol=0.001, join_columns="a")
-        assert is_match(rdf, float_off_df, abs_tol=0.001, join_columns="a")
-
-        assert not is_match(rdf, upper_case_df, join_columns="a")
-        assert is_match(rdf, upper_case_df, join_columns="a", ignore_case=True)
-
-        assert not is_match(rdf, space_df, join_columns="a")
-        assert is_match(rdf, space_df, join_columns="a", ignore_spaces=True)
-
-        assert is_match(rdf, upper_col_df, join_columns="a")
-        with raises(AssertionError):
-            is_match(rdf, upper_col_df, join_columns="a", cast_column_names_lower=False)
-
-        assert is_match(
-            duckdb.sql("SELECT 'a' AS a, 'b' AS b"),
-            duckdb.sql("SELECT 'a' AS a, 'b' AS b"),
-            join_columns="a",
-        )
-
-
-def test_doc_case():
-    data1 = """acct_id,dollar_amt,name,float_fld,date_fld
-    10000001234,123.45,George Maharis,14530.1555,2017-01-01
-    10000001235,0.45,Michael Bluth,1,2017-01-01
-    10000001236,1345,George Bluth,,2017-01-01
-    10000001237,123456,Bob Loblaw,345.12,2017-01-01
-    10000001239,1.05,Lucille Bluth,,2017-01-01
-    """
-
-    data2 = """acct_id,dollar_amt,name,float_fld
-    10000001234,123.4,George Michael Bluth,14530.155
-    10000001235,0.45,Michael Bluth,
-    10000001236,1345,George Bluth,1
-    10000001237,123456,Robert Loblaw,345.12
-    10000001238,1.05,Loose Seal Bluth,111
-    """
-
-    df1 = pd.read_csv(StringIO(data1))
-    df2 = pd.read_csv(StringIO(data2))
-
-    assert not is_match(
-        df1,
-        df2,
-        join_columns="acct_id",
-        abs_tol=0,
-        rel_tol=0,
-        df1_name="Original",
-        df2_name="New",
-        parallelism=2,
-    )
-
-
-def _compare_report(expected, actual, truncate=False):
-    if truncate:
-        expected = expected.split("Sample Rows", 1)[0]
-        actual = actual.split("Sample Rows", 1)[0]
-    assert expected == actual
-
-
-def test_report_pandas(
-    simple_diff_df1,
-    simple_diff_df2,
-    no_intersection_diff_df1,
-    no_intersection_diff_df2,
-    large_diff_df1,
-    large_diff_df2,
-):
-    comp = Compare(simple_diff_df1, simple_diff_df2, join_columns=["aa"])
-    a = report(simple_diff_df1, simple_diff_df2, ["aa"])
-    _compare_report(comp.report(), a)
-    a = report(simple_diff_df1, simple_diff_df2, "aa", parallelism=2)
-    _compare_report(comp.report(), a)
-
-    comp = Compare(
-        no_intersection_diff_df1, no_intersection_diff_df2, join_columns=["x"]
-    )
-    a = report(no_intersection_diff_df1, no_intersection_diff_df2, ["x"])
-    _compare_report(comp.report(), a)
-    a = report(no_intersection_diff_df1, no_intersection_diff_df2, "x", parallelism=2)
-    _compare_report(comp.report(), a)
-
-    # due to https://github.com/capitalone/datacompy/issues/221
-    # we can have y as a constant to ensure all the x matches are equal
-
-    comp = Compare(large_diff_df1, large_diff_df2, join_columns=["x"])
-    a = report(large_diff_df1, large_diff_df2, ["x"])
-    _compare_report(comp.report(), a, truncate=True)
-    a = report(large_diff_df1, large_diff_df2, "x", parallelism=2)
-    _compare_report(comp.report(), a, truncate=True)
-
-
-def test_report_spark(
-    spark_session,
-    simple_diff_df1,
-    simple_diff_df2,
-    no_intersection_diff_df1,
-    no_intersection_diff_df2,
-    large_diff_df1,
-    large_diff_df2,
-):
-    simple_diff_df1.iteritems = simple_diff_df1.items  # pandas 2 compatibility
-    simple_diff_df2.iteritems = simple_diff_df2.items  # pandas 2 compatibility
-    no_intersection_diff_df1.iteritems = (
-        no_intersection_diff_df1.items
-    )  # pandas 2 compatibility
-    no_intersection_diff_df2.iteritems = (
-        no_intersection_diff_df2.items
-    )  # pandas 2 compatibility
-    large_diff_df1.iteritems = large_diff_df1.items  # pandas 2 compatibility
-    large_diff_df2.iteritems = large_diff_df2.items  # pandas 2 compatibility
-
-    df1 = spark_session.createDataFrame(simple_diff_df1)
-    df2 = spark_session.createDataFrame(simple_diff_df2)
-    comp = Compare(simple_diff_df1, simple_diff_df2, join_columns="aa")
-    a = report(df1, df2, ["aa"])
-    _compare_report(comp.report(), a)
-
-    df1 = spark_session.createDataFrame(no_intersection_diff_df1)
-    df2 = spark_session.createDataFrame(no_intersection_diff_df2)
-    comp = Compare(no_intersection_diff_df1, no_intersection_diff_df2, join_columns="x")
-    a = report(df1, df2, ["x"])
-    _compare_report(comp.report(), a)
-
-    # due to https://github.com/capitalone/datacompy/issues/221
-    # we can have y as a constant to ensure all the x matches are equal
-
-    df1 = spark_session.createDataFrame(large_diff_df1)
-    df2 = spark_session.createDataFrame(large_diff_df2)
-    comp = Compare(large_diff_df1, large_diff_df2, join_columns="x")
-    a = report(df1, df2, ["x"])
-    _compare_report(comp.report(), a, truncate=True)
-
-
-def test_unique_columns_native(ref_df):
-    df1 = ref_df[0]
-    df1_copy = ref_df[1]
-    df2 = ref_df[2]
-    df3 = ref_df[3]
-
-    assert unq_columns(df1, df1.copy()) == OrderedSet()
-    assert unq_columns(df1, df2) == OrderedSet(["c"])
-    assert unq_columns(df1, df3) == OrderedSet(["a", "b"])
-    assert unq_columns(df1.copy(), df1) == OrderedSet()
-    assert unq_columns(df3, df2) == OrderedSet(["c"])
-
-
-def test_unique_columns_spark(spark_session, ref_df):
-    df1 = ref_df[0]
-    df1_copy = ref_df[1]
-    df2 = ref_df[2]
-    df3 = ref_df[3]
-
-    df1.iteritems = df1.items  # pandas 2 compatibility
-    df1_copy.iteritems = df1_copy.items  # pandas 2 compatibility
-    df2.iteritems = df2.items  # pandas 2 compatibility
-    df3.iteritems = df3.items  # pandas 2 compatibility
-
-    sdf1 = spark_session.createDataFrame(df1)
-    sdf1_copy = spark_session.createDataFrame(df1_copy)
-    sdf2 = spark_session.createDataFrame(df2)
-    sdf3 = spark_session.createDataFrame(df3)
-
-    assert unq_columns(sdf1, sdf1_copy) == OrderedSet()
-    assert unq_columns(sdf1, sdf2) == OrderedSet(["c"])
-    assert unq_columns(sdf1, sdf3) == OrderedSet(["a", "b"])
-    assert unq_columns(sdf1_copy, sdf1) == OrderedSet()
-    assert unq_columns(sdf3, sdf2) == OrderedSet(["c"])
-
-
-def test_unique_columns_polars(ref_df):
-    df1 = ref_df[0]
-    df1_copy = ref_df[1]
-    df2 = ref_df[2]
-    df3 = ref_df[3]
-
-    pdf1 = pl.from_pandas(df1)
-    pdf1_copy = pl.from_pandas(df1_copy)
-    pdf2 = pl.from_pandas(df2)
-    pdf3 = pl.from_pandas(df3)
-
-    assert unq_columns(pdf1, pdf1_copy) == OrderedSet()
-    assert unq_columns(pdf1, pdf2) == OrderedSet(["c"])
-    assert unq_columns(pdf1, pdf3) == OrderedSet(["a", "b"])
-    assert unq_columns(pdf1_copy, pdf1) == OrderedSet()
-    assert unq_columns(pdf3, pdf2) == OrderedSet(["c"])
-
-
-def test_unique_columns_duckdb(ref_df):
-    df1 = ref_df[0]
-    df1_copy = ref_df[1]
-    df2 = ref_df[2]
-    df3 = ref_df[3]
-
-    with duckdb.connect():
-        ddf1 = duckdb.from_df(df1)
-        ddf1_copy = duckdb.from_df(df1_copy)
-        ddf2 = duckdb.from_df(df2)
-        ddf3 = duckdb.from_df(df3)
-
-        assert unq_columns(ddf1, ddf1_copy) == OrderedSet()
-        assert unq_columns(ddf1, ddf2) == OrderedSet(["c"])
-        assert unq_columns(ddf1, ddf3) == OrderedSet(["a", "b"])
-        assert unq_columns(ddf1_copy, ddf1) == OrderedSet()
-        assert unq_columns(ddf3, ddf2) == OrderedSet(["c"])
-
-
-def test_intersect_columns_native(ref_df):
-    df1 = ref_df[0]
-    df1_copy = ref_df[1]
-    df2 = ref_df[2]
-    df3 = ref_df[3]
-
-    assert intersect_columns(df1, df1_copy) == OrderedSet(["a", "b", "c"])
-    assert intersect_columns(df1, df2) == OrderedSet(["a", "b"])
-    assert intersect_columns(df1, df3) == OrderedSet(["c"])
-    assert intersect_columns(df1_copy, df1) == OrderedSet(["a", "b", "c"])
-    assert intersect_columns(df3, df2) == OrderedSet()
-
-
-def test_intersect_columns_spark(spark_session, ref_df):
-    df1 = ref_df[0]
-    df1_copy = ref_df[1]
-    df2 = ref_df[2]
-    df3 = ref_df[3]
-
-    df1.iteritems = df1.items  # pandas 2 compatibility
-    df1_copy.iteritems = df1_copy.items  # pandas 2 compatibility
-    df2.iteritems = df2.items  # pandas 2 compatibility
-    df3.iteritems = df3.items  # pandas 2 compatibility
-
-    sdf1 = spark_session.createDataFrame(df1)
-    sdf1_copy = spark_session.createDataFrame(df1_copy)
-    sdf2 = spark_session.createDataFrame(df2)
-    sdf3 = spark_session.createDataFrame(df3)
-
-    assert intersect_columns(sdf1, sdf1_copy) == OrderedSet(["a", "b", "c"])
-    assert intersect_columns(sdf1, sdf2) == OrderedSet(["a", "b"])
-    assert intersect_columns(sdf1, sdf3) == OrderedSet(["c"])
-    assert intersect_columns(sdf1_copy, sdf1) == OrderedSet(["a", "b", "c"])
-    assert intersect_columns(sdf3, sdf2) == OrderedSet()
-
-
-def test_intersect_columns_polars(ref_df):
-    df1 = ref_df[0]
-    df1_copy = ref_df[1]
-    df2 = ref_df[2]
-    df3 = ref_df[3]
-
-    pdf1 = pl.from_pandas(df1)
-    pdf1_copy = pl.from_pandas(df1_copy)
-    pdf2 = pl.from_pandas(df2)
-    pdf3 = pl.from_pandas(df3)
-
-    assert intersect_columns(pdf1, pdf1_copy) == OrderedSet(["a", "b", "c"])
-    assert intersect_columns(pdf1, pdf2) == OrderedSet(["a", "b"])
-    assert intersect_columns(pdf1, pdf3) == OrderedSet(["c"])
-    assert intersect_columns(pdf1_copy, pdf1) == OrderedSet(["a", "b", "c"])
-    assert intersect_columns(pdf3, pdf2) == OrderedSet()
-
-
-def test_intersect_columns_duckdb(ref_df):
-    df1 = ref_df[0]
-    df1_copy = ref_df[1]
-    df2 = ref_df[2]
-    df3 = ref_df[3]
-
-    with duckdb.connect():
-        ddf1 = duckdb.from_df(df1)
-        ddf1_copy = duckdb.from_df(df1_copy)
-        ddf2 = duckdb.from_df(df2)
-        ddf3 = duckdb.from_df(df3)
-
-        assert intersect_columns(ddf1, ddf1_copy) == OrderedSet(["a", "b", "c"])
-        assert intersect_columns(ddf1, ddf2) == OrderedSet(["a", "b"])
-        assert intersect_columns(ddf1, ddf3) == OrderedSet(["c"])
-        assert intersect_columns(ddf1_copy, ddf1) == OrderedSet(["a", "b", "c"])
-        assert intersect_columns(ddf3, ddf2) == OrderedSet()
-
-
-def test_all_columns_match_native(ref_df):
-    df1 = ref_df[0]
-    df1_copy = ref_df[1]
-    df2 = ref_df[2]
-    df3 = ref_df[3]
-
-    assert all_columns_match(df1, df1_copy) is True
-    assert all_columns_match(df1, df2) is False
-    assert all_columns_match(df1, df3) is False
-    assert all_columns_match(df1_copy, df1) is True
-    assert all_columns_match(df3, df2) is False
-
-
-def test_all_columns_match_spark(spark_session, ref_df):
-    df1 = ref_df[0]
-    df1_copy = ref_df[1]
-    df2 = ref_df[2]
-    df3 = ref_df[3]
-
-    df1.iteritems = df1.items  # pandas 2 compatibility
-    df1_copy.iteritems = df1_copy.items  # pandas 2 compatibility
-    df2.iteritems = df2.items  # pandas 2 compatibility
-    df3.iteritems = df3.items  # pandas 2 compatibility
-
-    df1 = spark_session.createDataFrame(df1)
-    df1_copy = spark_session.createDataFrame(df1_copy)
-    df2 = spark_session.createDataFrame(df2)
-    df3 = spark_session.createDataFrame(df3)
-
-    assert all_columns_match(df1, df1_copy) is True
-    assert all_columns_match(df1, df2) is False
-    assert all_columns_match(df1, df3) is False
-    assert all_columns_match(df1_copy, df1) is True
-    assert all_columns_match(df3, df2) is False
-
-
-def test_all_columns_match_polars(ref_df):
-    df1 = ref_df[0]
-    df1_copy = ref_df[1]
-    df2 = ref_df[2]
-    df3 = ref_df[3]
-
-    df1 = pl.from_pandas(df1)
-    df1_copy = pl.from_pandas(df1_copy)
-    df2 = pl.from_pandas(df2)
-    df3 = pl.from_pandas(df3)
-
-    assert all_columns_match(df1, df1_copy) is True
-    assert all_columns_match(df1, df2) is False
-    assert all_columns_match(df1, df3) is False
-    assert all_columns_match(df1_copy, df1) is True
-    assert all_columns_match(df3, df2) is False
-
-
-def test_all_columns_match_duckdb(ref_df):
-    df1 = ref_df[0]
-    df1_copy = ref_df[1]
-    df2 = ref_df[2]
-    df3 = ref_df[3]
-
-    with duckdb.connect():
-        df1 = duckdb.from_df(df1)
-        df1_copy = duckdb.from_df(df1_copy)
-        df2 = duckdb.from_df(df2)
-        df3 = duckdb.from_df(df3)
-
-        assert all_columns_match(df1, df1_copy) is True
-        assert all_columns_match(df1, df2) is False
-        assert all_columns_match(df1, df3) is False
-        assert all_columns_match(df1_copy, df1) is True
-        assert all_columns_match(df3, df2) is False
-
-
-def test_all_rows_overlap_native(
-    ref_df,
-    shuffle_df,
-):
-    # defaults to Compare class
-    assert all_rows_overlap(ref_df[0], ref_df[0].copy(), join_columns="a")
-    assert all_rows_overlap(ref_df[0], shuffle_df, join_columns="a")
-    assert not all_rows_overlap(ref_df[0], ref_df[4], join_columns="a")
-    # Fugue
-    assert all_rows_overlap(ref_df[0], shuffle_df, join_columns="a", parallelism=2)
-    assert not all_rows_overlap(ref_df[0], ref_df[4], join_columns="a", parallelism=2)
-
-
-def test_all_rows_overlap_spark(
-    spark_session,
-    ref_df,
-    shuffle_df,
-):
-    ref_df[0].iteritems = ref_df[0].items  # pandas 2 compatibility
-    ref_df[4].iteritems = ref_df[4].items  # pandas 2 compatibility
-    shuffle_df.iteritems = shuffle_df.items  # pandas 2 compatibility
-    rdf = spark_session.createDataFrame(ref_df[0])
-    rdf_copy = spark_session.createDataFrame(ref_df[0])
-    rdf4 = spark_session.createDataFrame(ref_df[4])
-    sdf = spark_session.createDataFrame(shuffle_df)
-
-    assert all_rows_overlap(rdf, rdf_copy, join_columns="a")
-    assert all_rows_overlap(rdf, sdf, join_columns="a")
-    assert not all_rows_overlap(rdf, rdf4, join_columns="a")
-    assert all_rows_overlap(
-        spark_session.sql("SELECT 'a' AS a, 'b' AS b"),
-        spark_session.sql("SELECT 'a' AS a, 'b' AS b"),
-        join_columns="a",
-    )
-
-
-def test_all_rows_overlap_polars(
-    ref_df,
-    shuffle_df,
-):
-    rdf = pl.from_pandas(ref_df[0])
-    rdf_copy = pl.from_pandas(ref_df[0].copy())
-    rdf4 = pl.from_pandas(ref_df[4])
-    sdf = pl.from_pandas(shuffle_df)
-
-    assert all_rows_overlap(rdf, rdf_copy, join_columns="a")
-    assert all_rows_overlap(rdf, sdf, join_columns="a")
-    assert not all_rows_overlap(rdf, rdf4, join_columns="a")
-
-
-def test_all_rows_overlap_duckdb(
-    ref_df,
-    shuffle_df,
-):
-    with duckdb.connect():
-        rdf = duckdb.from_df(ref_df[0])
-        rdf_copy = duckdb.from_df(ref_df[0].copy())
-        rdf4 = duckdb.from_df(ref_df[4])
-        sdf = duckdb.from_df(shuffle_df)
-
-        assert all_rows_overlap(rdf, rdf_copy, join_columns="a")
-        assert all_rows_overlap(rdf, sdf, join_columns="a")
-        assert not all_rows_overlap(rdf, rdf4, join_columns="a")
-        assert all_rows_overlap(
-            duckdb.sql("SELECT 'a' AS a, 'b' AS b"),
-            duckdb.sql("SELECT 'a' AS a, 'b' AS b"),
-            join_columns="a",
-        )
diff --git a/tests/test_fugue/conftest.py b/tests/test_fugue/conftest.py
new file mode 100644
index 00000000..6a5683d2
--- /dev/null
+++ b/tests/test_fugue/conftest.py
@@ -0,0 +1,89 @@
+import pytest
+import numpy as np
+import pandas as pd
+
+
+@pytest.fixture
+def ref_df():
+    np.random.seed(0)
+
+    df1 = pd.DataFrame(
+        dict(
+            a=np.random.randint(0, 10, 100),
+            b=np.random.rand(100),
+            c=np.random.choice(["aaa", "b_c", "csd"], 100),
+        )
+    )
+    df1_copy = df1.copy()
+    df2 = df1.copy().drop(columns=["c"])
+    df3 = df1.copy().drop(columns=["a", "b"])
+    df4 = pd.DataFrame(
+        dict(
+            a=np.random.randint(1, 12, 100),  # shift the join col
+            b=np.random.rand(100),
+            c=np.random.choice(["aaa", "b_c", "csd"], 100),
+        )
+    )
+    return [df1, df1_copy, df2, df3, df4]
+
+
+@pytest.fixture
+def shuffle_df(ref_df):
+    return ref_df[0].sample(frac=1.0)
+
+
+@pytest.fixture
+def float_off_df(shuffle_df):
+    return shuffle_df.assign(b=shuffle_df.b + 0.0001)
+
+
+@pytest.fixture
+def upper_case_df(shuffle_df):
+    return shuffle_df.assign(c=shuffle_df.c.str.upper())
+
+
+@pytest.fixture
+def space_df(shuffle_df):
+    return shuffle_df.assign(c=shuffle_df.c + " ")
+
+
+@pytest.fixture
+def upper_col_df(shuffle_df):
+    return shuffle_df.rename(columns={"a": "A"})
+
+
+@pytest.fixture
+def simple_diff_df1():
+    return pd.DataFrame(dict(aa=[0, 1, 0], bb=[2.1, 3.1, 4.1])).convert_dtypes()
+
+
+@pytest.fixture
+def simple_diff_df2():
+    return pd.DataFrame(
+        dict(aa=[1, 0, 1], bb=[3.1, 4.1, 5.1], cc=["a", "b", "c"])
+    ).convert_dtypes()
+
+
+@pytest.fixture
+def no_intersection_diff_df1():
+    np.random.seed(0)
+    return pd.DataFrame(dict(x=["a"], y=[0.1])).convert_dtypes()
+
+
+@pytest.fixture
+def no_intersection_diff_df2():
+    return pd.DataFrame(dict(x=["b"], y=[1.1])).convert_dtypes()
+
+
+@pytest.fixture
+def large_diff_df1():
+    np.random.seed(0)
+    data = np.random.randint(0, 7, size=10000)
+    return pd.DataFrame({"x": data, "y": np.array([9] * 10000)}).convert_dtypes()
+
+
+@pytest.fixture
+def large_diff_df2():
+    np.random.seed(0)
+    data = np.random.randint(6, 11, size=10000)
+    return pd.DataFrame({"x": data, "y": np.array([9] * 10000)}).convert_dtypes()
diff --git a/tests/test_fugue/test_duckdb.py b/tests/test_fugue/test_duckdb.py
new file mode 100644
index 00000000..39465f42
--- /dev/null
+++ b/tests/test_fugue/test_duckdb.py
@@ -0,0 +1,140 @@
+#
+# Copyright 2020 Capital One Services, LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+"""Test fugue functionality with duckdb."""
+import pytest
+from ordered_set import OrderedSet
+from pytest import raises
+
+from datacompy import (
+    all_columns_match,
+    all_rows_overlap,
+    intersect_columns,
+    is_match,
+    unq_columns,
+)
+
+duckdb = pytest.importorskip("duckdb")
+
+
+def test_is_match_duckdb(
+    ref_df,
+    shuffle_df,
+    float_off_df,
+    upper_case_df,
+    space_df,
+    upper_col_df,
+):
+    with duckdb.connect():
+        rdf = duckdb.from_df(ref_df[0])
+
+        assert is_match(rdf, shuffle_df, join_columns="a")
+
+        assert not is_match(rdf, float_off_df, join_columns="a")
+        assert not is_match(rdf, float_off_df, abs_tol=0.00001, join_columns="a")
+        assert is_match(rdf, float_off_df, abs_tol=0.001, join_columns="a")
+        assert is_match(rdf, float_off_df, abs_tol=0.001, join_columns="a")
+
+        assert not is_match(rdf, upper_case_df, join_columns="a")
+        assert is_match(rdf, upper_case_df, join_columns="a", ignore_case=True)
+
+        assert not is_match(rdf, space_df, join_columns="a")
+        assert is_match(rdf, space_df, join_columns="a", ignore_spaces=True)
+
+        assert is_match(rdf, upper_col_df, join_columns="a")
+        with raises(AssertionError):
+            is_match(rdf, upper_col_df, join_columns="a", cast_column_names_lower=False)
+
+        assert is_match(
+            duckdb.sql("SELECT 'a' AS a, 'b' AS b"),
+            duckdb.sql("SELECT 'a' AS a, 'b' AS b"),
+            join_columns="a",
+        )
+
+
+def test_unique_columns_duckdb(ref_df):
+    df1 = ref_df[0]
+    df1_copy = ref_df[1]
+    df2 = ref_df[2]
+    df3 = ref_df[3]
+
+    with duckdb.connect():
+        ddf1 = duckdb.from_df(df1)
+        ddf1_copy = duckdb.from_df(df1_copy)
+        ddf2 = duckdb.from_df(df2)
+        ddf3 = duckdb.from_df(df3)
+
+        assert unq_columns(ddf1, ddf1_copy) == OrderedSet()
+        assert unq_columns(ddf1, ddf2) == OrderedSet(["c"])
+        assert unq_columns(ddf1, ddf3) == OrderedSet(["a", "b"])
+        assert unq_columns(ddf1_copy, ddf1) == OrderedSet()
+        assert unq_columns(ddf3, ddf2) == OrderedSet(["c"])
+
+
+def test_intersect_columns_duckdb(ref_df):
+    df1 = ref_df[0]
+    df1_copy = ref_df[1]
+    df2 = ref_df[2]
+    df3 = ref_df[3]
+
+    with duckdb.connect():
+        ddf1 = duckdb.from_df(df1)
+        ddf1_copy = duckdb.from_df(df1_copy)
+        ddf2 = duckdb.from_df(df2)
+        ddf3 = duckdb.from_df(df3)
+
+        assert intersect_columns(ddf1, ddf1_copy) == OrderedSet(["a", "b", "c"])
+        assert intersect_columns(ddf1, ddf2) == OrderedSet(["a", "b"])
+        assert intersect_columns(ddf1, ddf3) == OrderedSet(["c"])
+        assert intersect_columns(ddf1_copy, ddf1) == OrderedSet(["a", "b", "c"])
+        assert intersect_columns(ddf3, ddf2) == OrderedSet()
+
+
+def test_all_columns_match_duckdb(ref_df):
+    df1 = ref_df[0]
+    df1_copy = ref_df[1]
+    df2 = ref_df[2]
+    df3 = ref_df[3]
+
+    with duckdb.connect():
+        df1 = duckdb.from_df(df1)
+        df1_copy = duckdb.from_df(df1_copy)
+        df2 = duckdb.from_df(df2)
+        df3 = duckdb.from_df(df3)
+
+        assert all_columns_match(df1, df1_copy) is True
+        assert all_columns_match(df1, df2) is False
+        assert all_columns_match(df1, df3) is False
+        assert all_columns_match(df1_copy, df1) is True
+        assert all_columns_match(df3, df2) is False
+
+
+def test_all_rows_overlap_duckdb(
+    ref_df,
+    shuffle_df,
+):
+    with duckdb.connect():
+        rdf = duckdb.from_df(ref_df[0])
+        rdf_copy = duckdb.from_df(ref_df[0].copy())
+        rdf4 = duckdb.from_df(ref_df[4])
+        sdf = duckdb.from_df(shuffle_df)
+
+        assert all_rows_overlap(rdf, rdf_copy, join_columns="a")
+        assert all_rows_overlap(rdf, sdf, join_columns="a")
+        assert not all_rows_overlap(rdf, rdf4, join_columns="a")
+        assert all_rows_overlap(
+            duckdb.sql("SELECT 'a' AS a, 'b' AS b"),
+            duckdb.sql("SELECT 'a' AS a, 'b' AS b"),
+            join_columns="a",
+        )
diff --git a/tests/test_fugue/test_fugue_helpers.py b/tests/test_fugue/test_fugue_helpers.py
new file mode 100644
index 00000000..2c2d56a9
--- /dev/null
+++ b/tests/test_fugue/test_fugue_helpers.py
@@ -0,0 +1,22 @@
+#
+# Copyright 2020 Capital One Services, LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+"""One test helper for fugue reports."""
+
+def _compare_report(expected, actual, truncate=False):
+    """Compare datacompy reports."""
+    if truncate:
+        expected = expected.split("Sample Rows", 1)[0]
+        actual = actual.split("Sample Rows", 1)[0]
+    assert expected == actual
diff --git a/tests/test_fugue/test_fugue_pandas.py b/tests/test_fugue/test_fugue_pandas.py
new file mode 100644
index 00000000..3bacb30e
--- /dev/null
+++ b/tests/test_fugue/test_fugue_pandas.py
@@ -0,0 +1,194 @@
+#
+# Copyright 2023 Capital One Services, LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+"""Test the fugue functionality with pandas."""
+from io import StringIO
+import pandas as pd
+from ordered_set import OrderedSet
+from pytest import raises
+
+from datacompy import (
+    Compare,
+    all_columns_match,
+    all_rows_overlap,
+    intersect_columns,
+    is_match,
+    report,
+    unq_columns,
+)
+
+from test_fugue_helpers import _compare_report
+
+
+def test_is_match_native(
+    ref_df,
+    shuffle_df,
+    float_off_df,
+    upper_case_df,
+    space_df,
+    upper_col_df,
+):
+    # defaults to Compare class
+    assert is_match(ref_df[0], ref_df[0].copy(), join_columns="a")
+    assert not is_match(ref_df[0], shuffle_df, join_columns="a")
+    # Fugue
+    assert is_match(ref_df[0], shuffle_df, join_columns="a", parallelism=2)
+
+    assert not is_match(ref_df[0], float_off_df, join_columns="a", parallelism=2)
+    assert not is_match(
+        ref_df[0], float_off_df, abs_tol=0.00001, join_columns="a", parallelism=2
+    )
+    assert is_match(
+        ref_df[0], float_off_df, abs_tol=0.001, join_columns="a", parallelism=2
+    )
+    assert is_match(
+        ref_df[0], float_off_df, abs_tol=0.001, join_columns="a", parallelism=2
+    )
+
+    assert not is_match(ref_df[0], upper_case_df, join_columns="a", parallelism=2)
+    assert is_match(
+        ref_df[0], upper_case_df, join_columns="a", ignore_case=True, parallelism=2
+    )
+
+    assert not is_match(ref_df[0], space_df, join_columns="a", parallelism=2)
+    assert is_match(
+        ref_df[0], space_df, join_columns="a", ignore_spaces=True, parallelism=2
+    )
+
+    assert is_match(ref_df[0], upper_col_df, join_columns="a", parallelism=2)
+
+    with raises(AssertionError):
+        is_match(
+            ref_df[0],
+            upper_col_df,
+            join_columns="a",
+            cast_column_names_lower=False,
+            parallelism=2,
+        )
+
+
+def test_doc_case():
+    data1 = """acct_id,dollar_amt,name,float_fld,date_fld
+    10000001234,123.45,George Maharis,14530.1555,2017-01-01
+    10000001235,0.45,Michael Bluth,1,2017-01-01
+    10000001236,1345,George Bluth,,2017-01-01
+    10000001237,123456,Bob Loblaw,345.12,2017-01-01
+    10000001239,1.05,Lucille Bluth,,2017-01-01
+    """
+
+    data2 = """acct_id,dollar_amt,name,float_fld
+    10000001234,123.4,George Michael Bluth,14530.155
+    10000001235,0.45,Michael Bluth,
+    10000001236,1345,George Bluth,1
+    10000001237,123456,Robert Loblaw,345.12
+    10000001238,1.05,Loose Seal Bluth,111
+    """
+
+    df1 = pd.read_csv(StringIO(data1))
+    df2 = pd.read_csv(StringIO(data2))
+
+    assert not is_match(
+        df1,
+        df2,
+        join_columns="acct_id",
+        abs_tol=0,
+        rel_tol=0,
+        df1_name="Original",
+        df2_name="New",
+        parallelism=2,
+    )
+
+
+def test_report_pandas(
+    simple_diff_df1,
+    simple_diff_df2,
+    no_intersection_diff_df1,
+    no_intersection_diff_df2,
+    large_diff_df1,
+    large_diff_df2,
+):
+    comp = Compare(simple_diff_df1, simple_diff_df2, join_columns=["aa"])
+    a = report(simple_diff_df1, simple_diff_df2, ["aa"])
+    _compare_report(comp.report(), a)
+    a = report(simple_diff_df1, simple_diff_df2, "aa", parallelism=2)
+    _compare_report(comp.report(), a)
+
+    comp = Compare(
+        no_intersection_diff_df1, no_intersection_diff_df2, join_columns=["x"]
+    )
+    a = report(no_intersection_diff_df1, no_intersection_diff_df2, ["x"])
+    _compare_report(comp.report(), a)
+    a = report(no_intersection_diff_df1, no_intersection_diff_df2, "x", parallelism=2)
+    _compare_report(comp.report(), a)
+
+    # due to https://github.com/capitalone/datacompy/issues/221
+    # we can have y as a constant to ensure all the x matches are equal
+
+    comp = Compare(large_diff_df1, large_diff_df2, join_columns=["x"])
+    a = report(large_diff_df1, large_diff_df2, ["x"])
+    _compare_report(comp.report(), a, truncate=True)
+    a = report(large_diff_df1, large_diff_df2, "x", parallelism=2)
+    _compare_report(comp.report(), a, truncate=True)
+
+
+def test_unique_columns_native(ref_df):
+    df1 = ref_df[0]
+    df1_copy = ref_df[1]
+    df2 = ref_df[2]
+    df3 = ref_df[3]
+
+    assert unq_columns(df1, df1.copy()) == OrderedSet()
+    assert unq_columns(df1, df2) == OrderedSet(["c"])
+    assert unq_columns(df1, df3) == OrderedSet(["a", "b"])
+    assert unq_columns(df1.copy(), df1) == OrderedSet()
+    assert unq_columns(df3, df2) == OrderedSet(["c"])
+
+
+def test_intersect_columns_native(ref_df):
+    df1 = ref_df[0]
+    df1_copy = ref_df[1]
+    df2 = ref_df[2]
+    df3 = ref_df[3]
+
+    assert intersect_columns(df1, df1_copy) == OrderedSet(["a", "b", "c"])
+    assert intersect_columns(df1, df2) == OrderedSet(["a", "b"])
+    assert intersect_columns(df1, df3) == OrderedSet(["c"])
+    assert intersect_columns(df1_copy, df1) == OrderedSet(["a", "b", "c"])
+    assert intersect_columns(df3, df2) == OrderedSet()
+
+
+def test_all_columns_match_native(ref_df):
+    df1 = ref_df[0]
+    df1_copy = ref_df[1]
+    df2 = ref_df[2]
+    df3 = ref_df[3]
+
+    assert all_columns_match(df1, df1_copy) is True
+    assert all_columns_match(df1, df2) is False
+    assert all_columns_match(df1, df3) is False
+    assert all_columns_match(df1_copy, df1) is True
+    assert all_columns_match(df3, df2) is False
+
+
+def test_all_rows_overlap_native(
+    ref_df,
+    shuffle_df,
+):
+    # defaults to Compare class
+    assert all_rows_overlap(ref_df[0], ref_df[0].copy(), join_columns="a")
+    assert all_rows_overlap(ref_df[0], shuffle_df, join_columns="a")
+    assert not all_rows_overlap(ref_df[0], ref_df[4], join_columns="a")
+    # Fugue
+    assert all_rows_overlap(ref_df[0], shuffle_df, join_columns="a", parallelism=2)
+    assert not all_rows_overlap(ref_df[0], ref_df[4], join_columns="a", parallelism=2)
diff --git a/tests/test_fugue/test_fugue_polars.py b/tests/test_fugue/test_fugue_polars.py
new file mode 100644
index 00000000..97b88c7e
--- /dev/null
+++ b/tests/test_fugue/test_fugue_polars.py
@@ -0,0 +1,124 @@
+#
+# Copyright 2020 Capital One Services, LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+"""Test fugue and polars."""
+import pytest
+from ordered_set import OrderedSet
+from pytest import raises
+
+from datacompy import (
+    all_columns_match,
+    all_rows_overlap,
+    intersect_columns,
+    is_match,
+    unq_columns,
+)
+
+pl = pytest.importorskip("polars")
+
+
+def test_is_match_polars(
+    ref_df,
+    shuffle_df,
+    float_off_df,
+    upper_case_df,
+    space_df,
+    upper_col_df,
+):
+    rdf = pl.from_pandas(ref_df[0])
+
+    assert is_match(rdf, shuffle_df, join_columns="a")
+
+    assert not is_match(rdf, float_off_df, join_columns="a")
+    assert not is_match(rdf, float_off_df, abs_tol=0.00001, join_columns="a")
+    assert is_match(rdf, float_off_df, abs_tol=0.001, join_columns="a")
+    assert is_match(rdf, float_off_df, abs_tol=0.001, join_columns="a")
+
+    assert not is_match(rdf, upper_case_df, join_columns="a")
+    assert is_match(rdf, upper_case_df, join_columns="a", ignore_case=True)
+
+    assert not is_match(rdf, space_df, join_columns="a")
+    assert is_match(rdf, space_df, join_columns="a", ignore_spaces=True)
+
+    assert is_match(rdf, upper_col_df, join_columns="a")
+    with raises(AssertionError):
+        is_match(rdf, upper_col_df, join_columns="a", cast_column_names_lower=False)
+
+
+def test_unique_columns_polars(ref_df):
+    df1 = ref_df[0]
+    df1_copy = ref_df[1]
+    df2 = ref_df[2]
+    df3 = ref_df[3]
+
+    pdf1 = pl.from_pandas(df1)
+    pdf1_copy = pl.from_pandas(df1_copy)
+    pdf2 = pl.from_pandas(df2)
+    pdf3 = pl.from_pandas(df3)
+
+    assert unq_columns(pdf1, pdf1_copy) == OrderedSet()
+    assert unq_columns(pdf1, pdf2) == OrderedSet(["c"])
+    assert unq_columns(pdf1, pdf3) == OrderedSet(["a", "b"])
+    assert unq_columns(pdf1_copy, pdf1) == OrderedSet()
+    assert unq_columns(pdf3, pdf2) == OrderedSet(["c"])
+
+
+def test_intersect_columns_polars(ref_df):
+    df1 = ref_df[0]
+    df1_copy = ref_df[1]
+    df2 = ref_df[2]
+    df3 = ref_df[3]
+
+    pdf1 = pl.from_pandas(df1)
+    pdf1_copy = pl.from_pandas(df1_copy)
+    pdf2 = pl.from_pandas(df2)
+    pdf3 = pl.from_pandas(df3)
+
+    assert intersect_columns(pdf1, pdf1_copy) == OrderedSet(["a", "b", "c"])
+    assert intersect_columns(pdf1, pdf2) == OrderedSet(["a", "b"])
+    assert intersect_columns(pdf1, pdf3) == OrderedSet(["c"])
+    assert intersect_columns(pdf1_copy, pdf1) == OrderedSet(["a", "b", "c"])
+    assert intersect_columns(pdf3, pdf2) == OrderedSet()
+
+
+def test_all_columns_match_polars(ref_df):
+    df1 = ref_df[0]
+    df1_copy = ref_df[1]
+    df2 = ref_df[2]
+    df3 = ref_df[3]
+
+    df1 = pl.from_pandas(df1)
+    df1_copy = pl.from_pandas(df1_copy)
+    df2 = pl.from_pandas(df2)
+    df3 = pl.from_pandas(df3)
+
+    assert all_columns_match(df1, df1_copy) is True
+    assert all_columns_match(df1, df2) is False
+    assert all_columns_match(df1, df3) is False
+    assert all_columns_match(df1_copy, df1) is True
+    assert all_columns_match(df3, df2) is False
+
+
+def test_all_rows_overlap_polars(
+    ref_df,
+    shuffle_df,
+):
+    rdf = pl.from_pandas(ref_df[0])
+    rdf_copy = pl.from_pandas(ref_df[0].copy())
+    rdf4 = pl.from_pandas(ref_df[4])
+    sdf = pl.from_pandas(shuffle_df)
+
+    assert all_rows_overlap(rdf, rdf_copy, join_columns="a")
+    assert all_rows_overlap(rdf, sdf, join_columns="a")
+    assert not all_rows_overlap(rdf, rdf4, join_columns="a")
diff --git a/tests/test_fugue/test_fugue_spark.py b/tests/test_fugue/test_fugue_spark.py
new file mode 100644
index 00000000..0ef86c24
--- /dev/null
+++ b/tests/test_fugue/test_fugue_spark.py
@@ -0,0 +1,202 @@
+#
+# Copyright 2020 Capital One Services, LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+"""Test fugue and spark."""
+import pytest
+from datacompy import (
+    Compare,
+    all_columns_match,
+    all_rows_overlap,
+    intersect_columns,
+    is_match,
+    report,
+    unq_columns,
+)
+from ordered_set import OrderedSet
+from pytest import raises
+
+from test_fugue_helpers import _compare_report
+
+pyspark = pytest.importorskip("pyspark")
+
+
+def test_is_match_spark(
+    spark_session,
+    ref_df,
+    shuffle_df,
+    float_off_df,
+    upper_case_df,
+    space_df,
+    upper_col_df,
+):
+    ref_df[0].iteritems = ref_df[0].items  # pandas 2 compatibility
+    rdf = spark_session.createDataFrame(ref_df[0])
+
+    assert is_match(rdf, shuffle_df, join_columns="a")
+
+    assert not is_match(rdf, float_off_df, join_columns="a")
+    assert not is_match(rdf, float_off_df, abs_tol=0.00001, join_columns="a")
+    assert is_match(rdf, float_off_df, abs_tol=0.001, join_columns="a")
+    assert is_match(rdf, float_off_df, abs_tol=0.001, join_columns="a")
+
+    assert not is_match(rdf, upper_case_df, join_columns="a")
+    assert is_match(rdf, upper_case_df, join_columns="a", ignore_case=True)
+
+    assert not is_match(rdf, space_df, join_columns="a")
+    assert is_match(rdf, space_df, join_columns="a", ignore_spaces=True)
+
+    assert is_match(rdf, upper_col_df, join_columns="a")
+
+    with raises(AssertionError):
+        is_match(rdf, upper_col_df, join_columns="a", cast_column_names_lower=False)
+
+    assert is_match(
+        spark_session.sql("SELECT 'a' AS a, 'b' AS b"),
+        spark_session.sql("SELECT 'a' AS a, 'b' AS b"),
+        join_columns="a",
+    )
+
+
+def test_report_spark(
+    spark_session,
+    simple_diff_df1,
+    simple_diff_df2,
+    no_intersection_diff_df1,
+    no_intersection_diff_df2,
+    large_diff_df1,
+    large_diff_df2,
+):
+    simple_diff_df1.iteritems = simple_diff_df1.items  # pandas 2 compatibility
+    simple_diff_df2.iteritems = simple_diff_df2.items  # pandas 2 compatibility
+    no_intersection_diff_df1.iteritems = (
+        no_intersection_diff_df1.items
+    )  # pandas 2 compatibility
+    no_intersection_diff_df2.iteritems = (
+        no_intersection_diff_df2.items
+    )  # pandas 2 compatibility
+    large_diff_df1.iteritems = large_diff_df1.items  # pandas 2 compatibility
+    large_diff_df2.iteritems = large_diff_df2.items  # pandas 2 compatibility
+
+    df1 = spark_session.createDataFrame(simple_diff_df1)
+    df2 = spark_session.createDataFrame(simple_diff_df2)
+    comp = Compare(simple_diff_df1, simple_diff_df2, join_columns="aa")
+    a = report(df1, df2, ["aa"])
+    _compare_report(comp.report(), a)
+
+    df1 = spark_session.createDataFrame(no_intersection_diff_df1)
+    df2 = spark_session.createDataFrame(no_intersection_diff_df2)
+    comp = Compare(no_intersection_diff_df1, no_intersection_diff_df2, join_columns="x")
+    a = report(df1, df2, ["x"])
+    _compare_report(comp.report(), a)
+
+    # due to https://github.com/capitalone/datacompy/issues/221
+    # we can have y as a constant to ensure all the x matches are equal
+
+    df1 = spark_session.createDataFrame(large_diff_df1)
+    df2 = spark_session.createDataFrame(large_diff_df2)
+    comp = Compare(large_diff_df1, large_diff_df2, join_columns="x")
+    a = report(df1, df2, ["x"])
+    _compare_report(comp.report(), a, truncate=True)
+
+
+def test_unique_columns_spark(spark_session, ref_df):
+    df1 = ref_df[0]
+    df1_copy = ref_df[1]
+    df2 = ref_df[2]
+    df3 = ref_df[3]
+
+    df1.iteritems = df1.items  # pandas 2 compatibility
+    df1_copy.iteritems = df1_copy.items  # pandas 2 compatibility
+    df2.iteritems = df2.items  # pandas 2 compatibility
+    df3.iteritems = df3.items  # pandas 2 compatibility
+
+    sdf1 = spark_session.createDataFrame(df1)
+    sdf1_copy = spark_session.createDataFrame(df1_copy)
+    sdf2 = spark_session.createDataFrame(df2)
+    sdf3 = spark_session.createDataFrame(df3)
+
+    assert unq_columns(sdf1, sdf1_copy) == OrderedSet()
+    assert unq_columns(sdf1, sdf2) == OrderedSet(["c"])
+    assert unq_columns(sdf1, sdf3) == OrderedSet(["a", "b"])
+    assert unq_columns(sdf1_copy, sdf1) == OrderedSet()
+    assert unq_columns(sdf3, sdf2) == OrderedSet(["c"])
+
+
+def test_intersect_columns_spark(spark_session, ref_df):
+    df1 = ref_df[0]
+    df1_copy = ref_df[1]
+    df2 = ref_df[2]
+    df3 = ref_df[3]
+
+    df1.iteritems = df1.items  # pandas 2 compatibility
+    df1_copy.iteritems = df1_copy.items  # pandas 2 compatibility
+    df2.iteritems = df2.items  # pandas 2 compatibility
+    df3.iteritems = df3.items  # pandas 2 compatibility
+
+    sdf1 = spark_session.createDataFrame(df1)
+    sdf1_copy = spark_session.createDataFrame(df1_copy)
+    sdf2 = spark_session.createDataFrame(df2)
+    sdf3 = spark_session.createDataFrame(df3)
+
+    assert intersect_columns(sdf1, sdf1_copy) == OrderedSet(["a", "b", "c"])
+    assert intersect_columns(sdf1, sdf2) == OrderedSet(["a", "b"])
+    assert intersect_columns(sdf1, sdf3) == OrderedSet(["c"])
+    assert intersect_columns(sdf1_copy, sdf1) == OrderedSet(["a", "b", "c"])
+    assert intersect_columns(sdf3, sdf2) == OrderedSet()
+
+
+def test_all_columns_match_spark(spark_session, ref_df):
+    df1 = ref_df[0]
+    df1_copy = ref_df[1]
+    df2 = ref_df[2]
+    df3 = ref_df[3]
+
+    df1.iteritems = df1.items  # pandas 2 compatibility
+    df1_copy.iteritems = df1_copy.items  # pandas 2 compatibility
+    df2.iteritems = df2.items  # pandas 2 compatibility
+    df3.iteritems = df3.items  # pandas 2 compatibility
+
+    df1 = spark_session.createDataFrame(df1)
+    df1_copy = spark_session.createDataFrame(df1_copy)
+    df2 = spark_session.createDataFrame(df2)
+    df3 = spark_session.createDataFrame(df3)
+
+    assert all_columns_match(df1, df1_copy) is True
+    assert all_columns_match(df1, df2) is False
+    assert all_columns_match(df1, df3) is False
+    assert all_columns_match(df1_copy, df1) is True
+    assert all_columns_match(df3, df2) is False
+
+
+def test_all_rows_overlap_spark(
+    spark_session,
+    ref_df,
+    shuffle_df,
+):
+    ref_df[0].iteritems = ref_df[0].items  # pandas 2 compatibility
+    ref_df[4].iteritems = ref_df[4].items  # pandas 2 compatibility
+    shuffle_df.iteritems = shuffle_df.items  # pandas 2 compatibility
+    rdf = spark_session.createDataFrame(ref_df[0])
+    rdf_copy = spark_session.createDataFrame(ref_df[0])
+    rdf4 = spark_session.createDataFrame(ref_df[4])
+    sdf = spark_session.createDataFrame(shuffle_df)
+
+    assert all_rows_overlap(rdf, rdf_copy, join_columns="a")
+    assert all_rows_overlap(rdf, sdf, join_columns="a")
+    assert not all_rows_overlap(rdf, rdf4, join_columns="a")
+    assert all_rows_overlap(
+        spark_session.sql("SELECT 'a' AS a, 'b' AS b"),
+        spark_session.sql("SELECT 'a' AS a, 'b' AS b"),
+        join_columns="a",
+    )
diff --git a/tests/test_spark.py b/tests/test_spark.py
index c577a667..2babfb7f 100644
--- a/tests/test_spark.py
+++ b/tests/test_spark.py
@@ -20,6 +20,9 @@
 from decimal import Decimal
 
 import pytest
+
+pytest.importorskip("pyspark")
+
 from pyspark.sql import Row, SparkSession
 from pyspark.sql.types import (
     DateType,

From 01d2d8fb7a8c91c98ca62c086ab7bb436e182096 Mon Sep 17 00:00:00 2001
From: Faisal <faisal.dosani@pm.me>
Date: Thu, 18 Jan 2024 12:41:40 -0400
Subject: [PATCH 3/9] Native Polars support (#258)

* adding in first commit of Polars port

* small fixes to reporting

* renaming from core_polars to polars

* updating usage docs for polars

* updating docs and some clean up of README

* adding in pytest.importorskip

* adding in pytest.importorskip

* fixing imports

* fixing mypy and minor bugs

* fixing polars test bugs

* adding in abc class

* using base and cleanup
---
 README.md                    |  311 +-------
 datacompy/__init__.py        |    3 +-
 datacompy/base.py            |  141 ++++
 datacompy/core.py            |   16 +-
 datacompy/fugue.py           |    2 +-
 datacompy/polars.py          |  984 +++++++++++++++++++++++++
 datacompy/spark.py           |    2 +-
 docs/source/index.rst        |    1 +
 docs/source/install.rst      |    4 +-
 docs/source/pandas_usage.rst |    7 +
 docs/source/polars_usage.rst |  209 ++++++
 docs/source/spark_usage.rst  |  122 +++-
 tests/test_polars.py         | 1306 ++++++++++++++++++++++++++++++++++
 13 files changed, 2795 insertions(+), 313 deletions(-)
 create mode 100644 datacompy/base.py
 create mode 100644 datacompy/polars.py
 create mode 100644 docs/source/polars_usage.rst
 create mode 100644 tests/test_polars.py

diff --git a/README.md b/README.md
index c80f30ad..d1be5efa 100644
--- a/README.md
+++ b/README.md
@@ -38,308 +38,15 @@ pip install datacompy[ray]
 
 ```
 
-
-## Pandas Detail
-
-DataComPy will try to join two dataframes either on a list of join columns, or
-on indexes.  If the two dataframes have duplicates based on join values, the
-match process sorts by the remaining fields and joins based on that row number.
-
-Column-wise comparisons attempt to match values even when dtypes don't match.
-So if, for example, you have a column with ``decimal.Decimal`` values in one
-dataframe and an identically-named column with ``float64`` dtype in another,
-it will tell you that the dtypes are different but will still try to compare the
-values.
-
-
-### Basic Usage
-
-```python
-
-from io import StringIO
-import pandas as pd
-import datacompy
-
-data1 = """acct_id,dollar_amt,name,float_fld,date_fld
-10000001234,123.45,George Maharis,14530.1555,2017-01-01
-10000001235,0.45,Michael Bluth,1,2017-01-01
-10000001236,1345,George Bluth,,2017-01-01
-10000001237,123456,Bob Loblaw,345.12,2017-01-01
-10000001239,1.05,Lucille Bluth,,2017-01-01
-"""
-
-data2 = """acct_id,dollar_amt,name,float_fld
-10000001234,123.4,George Michael Bluth,14530.155
-10000001235,0.45,Michael Bluth,
-10000001236,1345,George Bluth,1
-10000001237,123456,Robert Loblaw,345.12
-10000001238,1.05,Loose Seal Bluth,111
-"""
-
-df1 = pd.read_csv(StringIO(data1))
-df2 = pd.read_csv(StringIO(data2))
-
-compare = datacompy.Compare(
-    df1,
-    df2,
-    join_columns='acct_id',  #You can also specify a list of columns
-    abs_tol=0, #Optional, defaults to 0
-    rel_tol=0, #Optional, defaults to 0
-    df1_name='Original', #Optional, defaults to 'df1'
-    df2_name='New' #Optional, defaults to 'df2'
-    )
-compare.matches(ignore_extra_columns=False)
-# False
-
-# This method prints out a human-readable report summarizing and sampling differences
-print(compare.report())
-```
-
-See docs for more detailed usage instructions and an example of the report output.
-
-
-### Things that are happening behind the scenes
-
-- You pass in two dataframes (``df1``, ``df2``) to ``datacompy.Compare`` and a
-  column to join on (or list of columns) to ``join_columns``.  By default the
-  comparison needs to match values exactly, but you can pass in ``abs_tol``
-  and/or ``rel_tol`` to apply absolute and/or relative tolerances for numeric columns.
-
-  - You can pass in ``on_index=True`` instead of ``join_columns`` to join on
-    the index instead.
-
-- The class validates that you passed dataframes, that they contain all of the
-  columns in `join_columns` and have unique column names other than that.  The
-  class also lowercases all column names to disambiguate.
-- On initialization the class validates inputs, and runs the comparison.
-- ``Compare.matches()`` will return ``True`` if the dataframes match, ``False``
-  otherwise.
-
-  - You can pass in ``ignore_extra_columns=True`` to not return ``False`` just
-    because there are non-overlapping column names (will still check on
-    overlapping columns)
-  - NOTE: if you only want to validate whether a dataframe matches exactly or
-    not, you should look at ``pandas.testing.assert_frame_equal``.  The main
-    use case for ``datacompy`` is when you need to interpret the difference
-    between two dataframes.
-
-- Compare also has some shortcuts like
-
-  - ``intersect_rows``, ``df1_unq_rows``, ``df2_unq_rows`` for getting
-    intersection, just df1 and just df2 records (DataFrames)
-  - ``intersect_columns()``, ``df1_unq_columns()``, ``df2_unq_columns()`` for
-    getting intersection, just df1 and just df2 columns (Sets)
-
-- You can turn on logging to see more detailed logs.
-
-
-## Fugue Detail
-
-[Fugue](https://github.com/fugue-project/fugue) is a Python library that provides a unified interface
-for data processing on Pandas, DuckDB, Polars, Arrow, Spark, Dask, Ray, and many other backends.
-DataComPy integrates with Fugue to provide a simple way to compare data across these backends.
-
-### Basic Usage
-
-The following usage example compares two Pandas dataframes, it is equivalent to the Pandas example above.
-
-```python
-from io import StringIO
-import pandas as pd
-import datacompy
-
-data1 = """acct_id,dollar_amt,name,float_fld,date_fld
-10000001234,123.45,George Maharis,14530.1555,2017-01-01
-10000001235,0.45,Michael Bluth,1,2017-01-01
-10000001236,1345,George Bluth,,2017-01-01
-10000001237,123456,Bob Loblaw,345.12,2017-01-01
-10000001239,1.05,Lucille Bluth,,2017-01-01
-"""
-
-data2 = """acct_id,dollar_amt,name,float_fld
-10000001234,123.4,George Michael Bluth,14530.155
-10000001235,0.45,Michael Bluth,
-10000001236,1345,George Bluth,1
-10000001237,123456,Robert Loblaw,345.12
-10000001238,1.05,Loose Seal Bluth,111
-"""
-
-df1 = pd.read_csv(StringIO(data1))
-df2 = pd.read_csv(StringIO(data2))
-
-datacompy.is_match(
-    df1,
-    df2,
-    join_columns='acct_id',  #You can also specify a list of columns
-    abs_tol=0, #Optional, defaults to 0
-    rel_tol=0, #Optional, defaults to 0
-    df1_name='Original', #Optional, defaults to 'df1'
-    df2_name='New' #Optional, defaults to 'df2'
-)
-# False
-
-# This method prints out a human-readable report summarizing and sampling differences
-print(datacompy.report(
-    df1,
-    df2,
-    join_columns='acct_id',  #You can also specify a list of columns
-    abs_tol=0, #Optional, defaults to 0
-    rel_tol=0, #Optional, defaults to 0
-    df1_name='Original', #Optional, defaults to 'df1'
-    df2_name='New' #Optional, defaults to 'df2'
-))
-```
-
-In order to compare dataframes of different backends, you just need to replace ``df1`` and ``df2`` with
-dataframes of different backends. Just pass in Dataframes such as Pandas dataframes, DuckDB relations,
-Polars dataframes, Arrow tables, Spark dataframes, Dask dataframes or Ray datasets. For example,
-to compare a Pandas dataframe with a Spark dataframe:
-
-```python  
-from pyspark.sql import SparkSession
-
-spark = SparkSession.builder.getOrCreate()
-spark_df2 = spark.createDataFrame(df2)
-datacompy.is_match(
-    df1,
-    spark_df2,
-    join_columns='acct_id',
-)
-```
-
-Notice that in order to use a specific backend, you need to have the corresponding library installed.
-For example, if you want compare Ray datasets, you must do
-
-```shell
-pip install datacompy[ray]
-```
-
-
-### How it works
-
-DataComPy uses Fugue to partition the two dataframes into chunks, and then compare each chunk in parallel
-using the Pandas-based ``Compare``. The comparison results are then aggregated to produce the final result.
-Different from the join operation used in ``SparkCompare``, the Fugue version uses the ``cogroup -> map``
-like semantic (not exactly the same, Fugue adopts a coarse version to achieve great performance), which
-guarantees full data comparison with consistent result compared to Pandas-based ``Compare``.
-
-
-## Spark Detail
-
-:::{important}
-With version ``v0.9.0`` SparkCompare now uses Null Safe (``<=>``) comparisons
-:::
-
-DataComPy's ``SparkCompare`` class will join two dataframes either on a list of join
-columns. It has the capability to map column names that may be different in each
-dataframe, including in the join columns. You are responsible for creating the
-dataframes from any source which Spark can handle and specifying a unique join
-key. If there are duplicates in either dataframe by join key, the match process
-will remove the duplicates before joining (and tell you how many duplicates were
-found).
-
-As with the Pandas-based ``Compare`` class, comparisons will be attempted even
-if dtypes don't match. Any schema differences will be reported in the output
-as well as in any mismatch reports, so that you can assess whether or not a
-type mismatch is a problem or not.
-
-The main reasons why you would choose to use ``SparkCompare`` over ``Compare``
-are that your data is too large to fit into memory, or you're comparing data
-that works well in a Spark environment, like partitioned Parquet, CSV, or JSON
-files, or Cerebro tables.
-
-### Performance Implications
-
-
-Spark scales incredibly well, so you can use ``SparkCompare`` to compare
-billions of rows of data, provided you spin up a big enough cluster. Still,
-joining billions of rows of data is an inherently large task, so there are a
-couple of things you may want to take into consideration when getting into the
-cliched realm of "big data":
-
-* ``SparkCompare`` will compare all columns in common in the dataframes and
-  report on the rest. If there are columns in the data that you don't care to
-  compare, use a ``select`` statement/method on the dataframe(s) to filter
-  those out. Particularly when reading from wide Parquet files, this can make
-  a huge difference when the columns you don't care about don't have to be
-  read into memory and included in the joined dataframe.
-* For large datasets, adding ``cache_intermediates=True`` to the ``SparkCompare``
-  call can help optimize performance by caching certain intermediate dataframes
-  in memory, like the de-duped version of each input dataset, or the joined
-  dataframe. Otherwise, Spark's lazy evaluation will recompute those each time
-  it needs the data in a report or as you access instance attributes. This may
-  be fine for smaller dataframes, but will be costly for larger ones. You do
-  need to ensure that you have enough free cache memory before you do this, so
-  this parameter is set to False by default.
-
-
-### Basic Usage
-
-```python
-
-    import datetime
-    import datacompy
-    from pyspark.sql import Row
-
-    # This example assumes you have a SparkSession named "spark" in your environment, as you
-    # do when running `pyspark` from the terminal or in a Databricks notebook (Spark v2.0 and higher)
-
-    data1 = [
-        Row(acct_id=10000001234, dollar_amt=123.45, name='George Maharis', float_fld=14530.1555,
-            date_fld=datetime.date(2017, 1, 1)),
-        Row(acct_id=10000001235, dollar_amt=0.45, name='Michael Bluth', float_fld=1.0,
-            date_fld=datetime.date(2017, 1, 1)),
-        Row(acct_id=10000001236, dollar_amt=1345.0, name='George Bluth', float_fld=None,
-            date_fld=datetime.date(2017, 1, 1)),
-        Row(acct_id=10000001237, dollar_amt=123456.0, name='Bob Loblaw', float_fld=345.12,
-            date_fld=datetime.date(2017, 1, 1)),
-        Row(acct_id=10000001239, dollar_amt=1.05, name='Lucille Bluth', float_fld=None,
-            date_fld=datetime.date(2017, 1, 1))
-    ]
-
-    data2 = [
-        Row(acct_id=10000001234, dollar_amt=123.4, name='George Michael Bluth', float_fld=14530.155),
-        Row(acct_id=10000001235, dollar_amt=0.45, name='Michael Bluth', float_fld=None),
-        Row(acct_id=10000001236, dollar_amt=1345.0, name='George Bluth', float_fld=1.0),
-        Row(acct_id=10000001237, dollar_amt=123456.0, name='Robert Loblaw', float_fld=345.12),
-        Row(acct_id=10000001238, dollar_amt=1.05, name='Loose Seal Bluth', float_fld=111.0)
-    ]
-
-    base_df = spark.createDataFrame(data1)
-    compare_df = spark.createDataFrame(data2)
-
-    comparison = datacompy.SparkCompare(spark, base_df, compare_df, join_columns=['acct_id'])
-
-    # This prints out a human-readable report summarizing differences
-    comparison.report()
-```
-
-### Using SparkCompare on EMR or standalone Spark
-
-1. Set proxy variables
-2. Create a virtual environment, if desired (``virtualenv venv; source venv/bin/activate``)
-3. Pip install datacompy and requirements
-4. Ensure your SPARK_HOME environment variable is set (this is probably ``/usr/lib/spark`` but may
-   differ based on your installation)
-5. Augment your PYTHONPATH environment variable with
-   ``export PYTHONPATH=$SPARK_HOME/python/lib/py4j-0.10.4-src.zip:$SPARK_HOME/python:$PYTHONPATH``
-   (note that your version of py4j may differ depending on the version of Spark you're using)
-
-
-### Using SparkCompare on Databricks
-
-1. Clone this repository locally
-2. Create a datacompy egg by running ``python setup.py bdist_egg`` from the repo root directory.
-3. From the Databricks front page, click the "Library" link under the "New" section.
-4. On the New library page:
-    a. Change source to "Upload Python Egg or PyPi"
-    b. Under "Upload Egg", Library Name should be "datacompy"
-    c. Drag the egg file in datacompy/dist/ to the "Drop library egg here to upload" box
-    d. Click the "Create Library" button
-5. Once the library has been created, from the library page (which you can find in your /Users/{login} workspace),
-   you can choose clusters to attach the library to.
-6. ``import datacompy`` in a notebook attached to the cluster that the library is attached to and enjoy!
-
+## Supported backends
+
+- Pandas: ([See documentation](https://capitalone.github.io/datacompy/pandas_usage.html))
+- Spark: ([See documentation](https://capitalone.github.io/datacompy/spark_usage.html))
+- Polars (Experimental): ([See documentation](https://capitalone.github.io/datacompy/polars_usage.html))
+- Fugue is a Python library that provides a unified interface for data processing on Pandas, DuckDB, Polars, Arrow, 
+  Spark, Dask, Ray, and many other backends. DataComPy integrates with Fugue to provide a simple way to compare data 
+  across these backends. Please note that Fugue will use the Pandas (Native) logic at its lowest level 
+  ([See documentation](https://capitalone.github.io/datacompy/fugue_usage.html))
 
 ## Contributors
 
diff --git a/datacompy/__init__.py b/datacompy/__init__.py
index 7608f8cb..39231fc1 100644
--- a/datacompy/__init__.py
+++ b/datacompy/__init__.py
@@ -13,7 +13,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-__version__ = "0.10.5"
+__version__ = "0.11.0"
 
 from datacompy.core import *
 from datacompy.fugue import (
@@ -24,4 +24,5 @@
     report,
     unq_columns,
 )
+from datacompy.polars import PolarsCompare
 from datacompy.spark import NUMERIC_SPARK_TYPES, SparkCompare
diff --git a/datacompy/base.py b/datacompy/base.py
new file mode 100644
index 00000000..23a815fc
--- /dev/null
+++ b/datacompy/base.py
@@ -0,0 +1,141 @@
+#
+# Copyright 2024 Capital One Services, LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""
+Compare two Pandas DataFrames
+
+Originally this package was meant to provide similar functionality to
+PROC COMPARE in SAS - i.e. human-readable reporting on the difference between
+two dataframes.
+"""
+
+import logging
+from abc import ABC, abstractmethod
+from typing import Any, Optional
+
+from ordered_set import OrderedSet
+
+LOG = logging.getLogger(__name__)
+
+
+class BaseCompare(ABC):
+    @property
+    def df1(self) -> Any:
+        return self._df1  # type: ignore
+
+    @df1.setter
+    @abstractmethod
+    def df1(self, df1: Any) -> None:
+        """Check that it is a dataframe and has the join columns"""
+        pass
+
+    @property
+    def df2(self) -> Any:
+        return self._df2  # type: ignore
+
+    @df2.setter
+    @abstractmethod
+    def df2(self, df2: Any) -> None:
+        """Check that it is a dataframe and has the join columns"""
+        pass
+
+    @abstractmethod
+    def _validate_dataframe(
+        self, index: str, cast_column_names_lower: bool = True
+    ) -> None:
+        """Check that it is a dataframe and has the join columns"""
+        pass
+
+    @abstractmethod
+    def _compare(self, ignore_spaces: bool, ignore_case: bool) -> None:
+        """Actually run the comparison.  This tries to run df1.equals(df2)
+        first so that if they're truly equal we can tell.
+
+        This method will log out information about what is different between
+        the two dataframes, and will also return a boolean.
+        """
+        pass
+
+    @abstractmethod
+    def df1_unq_columns(self) -> OrderedSet[str]:
+        """Get columns that are unique to df1"""
+        pass
+
+    @abstractmethod
+    def df2_unq_columns(self) -> OrderedSet[str]:
+        """Get columns that are unique to df2"""
+        pass
+
+    @abstractmethod
+    def intersect_columns(self) -> OrderedSet[str]:
+        """Get columns that are shared between the two dataframes"""
+        pass
+
+    @abstractmethod
+    def _dataframe_merge(self, ignore_spaces: bool) -> None:
+        """Merge df1 to df2 on the join columns, to get df1 - df2, df2 - df1
+        and df1 & df2
+
+        If ``on_index`` is True, this will join on index values, otherwise it
+        will join on the ``join_columns``.
+        """
+        pass
+
+    @abstractmethod
+    def _intersect_compare(self, ignore_spaces: bool, ignore_case: bool) -> None:
+        pass
+
+    @abstractmethod
+    def all_columns_match(self) -> bool:
+        pass
+
+    @abstractmethod
+    def all_rows_overlap(self) -> bool:
+        pass
+
+    @abstractmethod
+    def count_matching_rows(self) -> int:
+        pass
+
+    @abstractmethod
+    def intersect_rows_match(self) -> bool:
+        pass
+
+    @abstractmethod
+    def matches(self, ignore_extra_columns: bool = False) -> bool:
+        pass
+
+    @abstractmethod
+    def subset(self) -> bool:
+        pass
+
+    @abstractmethod
+    def sample_mismatch(
+        self, column: str, sample_count: int = 10, for_display: bool = False
+    ) -> Any:
+        pass
+
+    @abstractmethod
+    def all_mismatch(self, ignore_matching_cols: bool = False) -> Any:
+        pass
+
+    @abstractmethod
+    def report(
+        self,
+        sample_count: int = 10,
+        column_count: int = 10,
+        html_file: Optional[str] = None,
+    ) -> str:
+        pass
diff --git a/datacompy/core.py b/datacompy/core.py
index fda507fb..8472ff1b 100644
--- a/datacompy/core.py
+++ b/datacompy/core.py
@@ -22,16 +22,18 @@
 """
 import logging
 import os
-from typing import cast, Any, List, Dict, Union, Optional
+from typing import Any, Dict, List, Optional, Union, cast
 
 import numpy as np
 import pandas as pd
 from ordered_set import OrderedSet
 
+from datacompy.base import BaseCompare
+
 LOG = logging.getLogger(__name__)
 
 
-class Compare:
+class Compare(BaseCompare):
     """Comparison class to be used to compare whether two dataframes as equal.
 
     Both df1 and df2 should be dataframes containing all of the join_columns,
@@ -418,6 +420,11 @@ def matches(self, ignore_extra_columns: bool = False) -> bool:
         ----------
         ignore_extra_columns : bool
             Ignores any columns in one dataframe and not in the other.
+
+        Returns
+        -------
+        bool
+            True or False if the dataframes match.
         """
         if not ignore_extra_columns and not self.all_columns_match():
             return False
@@ -434,6 +441,11 @@ def subset(self) -> bool:
         Dataframe 2 is considered a subset if all of its columns are in
         dataframe 1, and all of its rows match rows in dataframe 1 for the
         shared columns.
+
+        Returns
+        -------
+        bool
+            True if dataframe 2 is a subset of dataframe 1.
         """
         if not self.df2_unq_columns() == set():
             return False
diff --git a/datacompy/fugue.py b/datacompy/fugue.py
index 9a0109f4..360cbe17 100644
--- a/datacompy/fugue.py
+++ b/datacompy/fugue.py
@@ -20,7 +20,7 @@
 import logging
 import pickle
 from collections import defaultdict
-from typing import Any, Callable, Dict, Iterable, List, cast, Union, Optional, Tuple
+from typing import Any, Callable, Dict, Iterable, List, Optional, Tuple, Union, cast
 
 import fugue.api as fa
 import pandas as pd
diff --git a/datacompy/polars.py b/datacompy/polars.py
new file mode 100644
index 00000000..0ea879c9
--- /dev/null
+++ b/datacompy/polars.py
@@ -0,0 +1,984 @@
+#
+# Copyright 2020 Capital One Services, LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""
+Compare two Polars DataFrames
+
+Originally this package was meant to provide similar functionality to
+PROC COMPARE in SAS - i.e. human-readable reporting on the difference between
+two dataframes.
+"""
+import logging
+import os
+from copy import deepcopy
+from typing import Any, Dict, List, Optional, Union, cast
+
+import numpy as np
+from ordered_set import OrderedSet
+
+from datacompy.base import BaseCompare
+
+try:
+    import polars as pl
+    from polars.exceptions import ComputeError, InvalidOperationError
+except ImportError:
+    pass  # Let non-Polars people at least enjoy the loveliness of the pandas datacompy functionality
+
+LOG = logging.getLogger(__name__)
+
+STRING_TYPE = ["String", "Utf8"]
+DATE_TYPE = ["Date", "Datetime"]
+
+
+class PolarsCompare(BaseCompare):
+    """Comparison class to be used to compare whether two dataframes as equal.
+
+    Both df1 and df2 should be dataframes containing all of the join_columns,
+    with unique column names. Differences between values are compared to
+    abs_tol + rel_tol * abs(df2['value']).
+
+    Parameters
+    ----------
+    df1 : Polars ``DataFrame``
+        First dataframe to check
+    df2 : Polars ``DataFrame``
+        Second dataframe to check
+    join_columns : list or str
+        Column(s) to join dataframes on.  If a string is passed in, that one
+        column will be used.
+    abs_tol : float, optional
+        Absolute tolerance between two values.
+    rel_tol : float, optional
+        Relative tolerance between two values.
+    df1_name : str, optional
+        A string name for the first dataframe.  This allows the reporting to
+        print out an actual name instead of "df1", and allows human users to
+        more easily track the dataframes.
+    df2_name : str, optional
+        A string name for the second dataframe
+    ignore_spaces : bool, optional
+        Flag to strip whitespace (including newlines) from string columns (including any join
+        columns)
+    ignore_case : bool, optional
+        Flag to ignore the case of string columns
+    cast_column_names_lower: bool, optional
+        Boolean indicator that controls of column names will be cast into lower case
+
+    Attributes
+    ----------
+    df1_unq_rows : Polars ``DataFrame``
+        All records that are only in df1 (based on a join on join_columns)
+    df2_unq_rows : Polars ``DataFrame``
+        All records that are only in df2 (based on a join on join_columns)
+    """
+
+    def __init__(
+        self,
+        df1: "pl.DataFrame",
+        df2: "pl.DataFrame",
+        join_columns: Union[List[str], str],
+        abs_tol: float = 0,
+        rel_tol: float = 0,
+        df1_name: str = "df1",
+        df2_name: str = "df2",
+        ignore_spaces: bool = False,
+        ignore_case: bool = False,
+        cast_column_names_lower: bool = True,
+    ) -> None:
+        self.cast_column_names_lower = cast_column_names_lower
+
+        if isinstance(join_columns, str):
+            self.join_columns = [
+                str(join_columns).lower()
+                if self.cast_column_names_lower
+                else str(join_columns)
+            ]
+        elif isinstance(join_columns, list):
+            self.join_columns = [
+                str(col).lower() if self.cast_column_names_lower else str(col)
+                for col in join_columns
+            ]
+        else:
+            raise TypeError(f"{join_columns} must be a string or list of string(s)")
+
+        self._any_dupes: bool = False
+        self.df1 = df1
+        self.df2 = df2
+        self.df1_name = df1_name
+        self.df2_name = df2_name
+        self.abs_tol = abs_tol
+        self.rel_tol = rel_tol
+        self.ignore_spaces = ignore_spaces
+        self.ignore_case = ignore_case
+        self.df1_unq_rows: "pl.DataFrame"
+        self.df2_unq_rows: "pl.DataFrame"
+        self.intersect_rows: "pl.DataFrame"
+        self.column_stats: List[Dict[str, Any]] = []
+        self._compare(ignore_spaces=ignore_spaces, ignore_case=ignore_case)
+
+    @property
+    def df1(self) -> "pl.DataFrame":
+        return self._df1
+
+    @df1.setter
+    def df1(self, df1: "pl.DataFrame") -> None:
+        """Check that it is a dataframe and has the join columns"""
+        self._df1 = df1
+        self._validate_dataframe(
+            "df1", cast_column_names_lower=self.cast_column_names_lower
+        )
+
+    @property
+    def df2(self) -> "pl.DataFrame":
+        return self._df2
+
+    @df2.setter
+    def df2(self, df2: "pl.DataFrame") -> None:
+        """Check that it is a dataframe and has the join columns"""
+        self._df2 = df2
+        self._validate_dataframe(
+            "df2", cast_column_names_lower=self.cast_column_names_lower
+        )
+
+    def _validate_dataframe(
+        self, index: str, cast_column_names_lower: bool = True
+    ) -> None:
+        """Check that it is a dataframe and has the join columns
+
+        Parameters
+        ----------
+        index : str
+            The "index" of the dataframe - df1 or df2.
+        cast_column_names_lower: bool, optional
+            Boolean indicator that controls of column names will be cast into lower case
+        """
+        dataframe = getattr(self, index)
+        if not isinstance(dataframe, pl.DataFrame):
+            raise TypeError(f"{index} must be a Polars DataFrame")
+
+        if cast_column_names_lower:
+            dataframe.columns = [str(col).lower() for col in dataframe.columns]
+
+        # Check if join_columns are present in the dataframe
+        if not set(self.join_columns).issubset(set(dataframe.columns)):
+            raise ValueError(f"{index} must have all columns from join_columns")
+
+        if len(set(dataframe.columns)) < len(dataframe.columns):
+            raise ValueError(f"{index} must have unique column names")
+
+        if len(dataframe.unique(subset=self.join_columns)) < len(dataframe):
+            self._any_dupes = True
+
+    def _compare(self, ignore_spaces: bool, ignore_case: bool) -> None:
+        """Actually run the comparison.  This tries to run df1.equals(df2)
+        first so that if they're truly equal we can tell.
+
+        This method will log out information about what is different between
+        the two dataframes, and will also return a boolean.
+        """
+        LOG.debug("Checking equality")
+        if self.df1.equals(self.df2):
+            LOG.info("df1 Polars.DataFrame.equals df2")
+        else:
+            LOG.info("df1 does not Polars.DataFrame.equals df2")
+        LOG.info(f"Number of columns in common: {len(self.intersect_columns())}")
+        LOG.debug("Checking column overlap")
+        for col in self.df1_unq_columns():
+            LOG.info(f"Column in df1 and not in df2: {col}")
+        LOG.info(
+            f"Number of columns in df1 and not in df2: {len(self.df1_unq_columns())}"
+        )
+        for col in self.df2_unq_columns():
+            LOG.info(f"Column in df2 and not in df1: {col}")
+        LOG.info(
+            f"Number of columns in df2 and not in df1: {len(self.df2_unq_columns())}"
+        )
+        LOG.debug("Merging dataframes")
+        self._dataframe_merge(ignore_spaces)
+        self._intersect_compare(ignore_spaces, ignore_case)
+        if self.matches():
+            LOG.info("df1 matches df2")
+        else:
+            LOG.info("df1 does not match df2")
+
+    def df1_unq_columns(self) -> OrderedSet[str]:
+        """Get columns that are unique to df1"""
+        return cast(
+            OrderedSet[str], OrderedSet(self.df1.columns) - OrderedSet(self.df2.columns)
+        )
+
+    def df2_unq_columns(self) -> OrderedSet[str]:
+        """Get columns that are unique to df2"""
+        return cast(
+            OrderedSet[str], OrderedSet(self.df2.columns) - OrderedSet(self.df1.columns)
+        )
+
+    def intersect_columns(self) -> OrderedSet[str]:
+        """Get columns that are shared between the two dataframes"""
+        return OrderedSet(self.df1.columns) & OrderedSet(self.df2.columns)
+
+    def _dataframe_merge(self, ignore_spaces: bool) -> None:
+        """Merge df1 to df2 on the join columns, to get df1 - df2, df2 - df1
+        and df1 & df2
+        """
+        params: Dict[str, Any]
+        LOG.debug("Outer joining")
+
+        df1 = self.df1.clone()
+        df2 = self.df2.clone()
+        temp_join_columns = deepcopy(self.join_columns)
+
+        if self._any_dupes:
+            LOG.debug("Duplicate rows found, deduping by order of remaining fields")
+            # Create order column for uniqueness of match
+            order_column = temp_column_name(df1, df2)
+            df1 = df1.with_columns(
+                generate_id_within_group(df1, temp_join_columns).alias(order_column)
+            )
+            df2 = df2.with_columns(
+                generate_id_within_group(df2, temp_join_columns).alias(order_column)
+            )
+            temp_join_columns.append(order_column)
+
+        params = {"on": temp_join_columns}
+
+        if ignore_spaces:
+            for column in self.join_columns:
+                if str(df1[column].dtype) in STRING_TYPE:
+                    df1 = df1.with_columns(pl.col(column).str.strip_chars())
+                if str(df2[column].dtype) in STRING_TYPE:
+                    df2 = df2.with_columns(pl.col(column).str.strip_chars())
+
+        df1_non_join_columns = OrderedSet(df1.columns) - OrderedSet(temp_join_columns)
+        df2_non_join_columns = OrderedSet(df2.columns) - OrderedSet(temp_join_columns)
+
+        for c in df1_non_join_columns:
+            df1 = df1.rename({c: c + "_df1"})
+        for c in df2_non_join_columns:
+            df2 = df2.rename({c: c + "_df2"})
+
+        # generate merge indicator
+        df1 = df1.with_columns(_merge_left=pl.lit(True))
+        df2 = df2.with_columns(_merge_right=pl.lit(True))
+
+        outer_join = df1.join(df2, how="outer_coalesce", join_nulls=True, **params)
+
+        # process merge indicator
+        outer_join = outer_join.with_columns(
+            pl.when((pl.col("_merge_left") == True) & (pl.col("_merge_right") == True))
+            .then(pl.lit("both"))
+            .when((pl.col("_merge_left") == True) & (pl.col("_merge_right").is_null()))
+            .then(pl.lit("left_only"))
+            .when((pl.col("_merge_left").is_null()) & (pl.col("_merge_right") == True))
+            .then(pl.lit("right_only"))
+            .alias("_merge")
+        )
+
+        # Clean up temp columns for duplicate row matching
+        if self._any_dupes:
+            outer_join = outer_join.drop(order_column)
+
+        df1_cols = get_merged_columns(self.df1, outer_join, "_df1")
+        df2_cols = get_merged_columns(self.df2, outer_join, "_df2")
+
+        LOG.debug("Selecting df1 unique rows")
+        self.df1_unq_rows = outer_join.filter(
+            outer_join["_merge"] == "left_only"
+        ).select(df1_cols)
+        self.df1_unq_rows.columns = self.df1.columns
+
+        LOG.debug("Selecting df2 unique rows")
+        self.df2_unq_rows = outer_join.filter(
+            outer_join["_merge"] == "right_only"
+        ).select(df2_cols)
+        self.df2_unq_rows.columns = self.df2.columns
+
+        LOG.info(f"Number of rows in df1 and not in df2: {len(self.df1_unq_rows)}")
+        LOG.info(f"Number of rows in df2 and not in df1: {len(self.df2_unq_rows)}")
+
+        LOG.debug("Selecting intersecting rows")
+        self.intersect_rows = outer_join.filter(outer_join["_merge"] == "both")
+        LOG.info(
+            f"Number of rows in df1 and df2 (not necessarily equal): {len(self.intersect_rows)}"
+        )
+
+    def _intersect_compare(self, ignore_spaces: bool, ignore_case: bool) -> None:
+        """Run the comparison on the intersect dataframe
+
+        This loops through all columns that are shared between df1 and df2, and
+        creates a column column_match which is True for matches, False
+        otherwise.
+        """
+        match_cnt: Union[int, float]
+        null_diff: Union[int, float]
+
+        LOG.debug("Comparing intersection")
+        row_cnt = len(self.intersect_rows)
+        for column in self.intersect_columns():
+            if column in self.join_columns:
+                match_cnt = row_cnt
+                col_match = ""
+                max_diff = 0.0
+                null_diff = 0
+            else:
+                col_1 = column + "_df1"
+                col_2 = column + "_df2"
+                col_match = column + "_match"
+                self.intersect_rows = self.intersect_rows.with_columns(
+                    columns_equal(
+                        self.intersect_rows[col_1],
+                        self.intersect_rows[col_2],
+                        self.rel_tol,
+                        self.abs_tol,
+                        ignore_spaces,
+                        ignore_case,
+                    ).alias(col_match)
+                )
+                match_cnt = self.intersect_rows[col_match].sum()
+                max_diff = calculate_max_diff(
+                    self.intersect_rows[col_1], self.intersect_rows[col_2]
+                )
+                null_diff = (
+                    (self.intersect_rows[col_1].is_null())
+                    ^ (self.intersect_rows[col_2].is_null())
+                ).sum()
+            if row_cnt > 0:
+                match_rate = float(match_cnt) / row_cnt
+            else:
+                match_rate = 0
+            LOG.info(f"{column}: {match_cnt} / {row_cnt} ({match_rate:.2%}) match")
+
+            self.column_stats.append(
+                {
+                    "column": column,
+                    "match_column": col_match,
+                    "match_cnt": match_cnt,
+                    "unequal_cnt": row_cnt - match_cnt,
+                    "dtype1": str(self.df1[column].dtype),
+                    "dtype2": str(self.df2[column].dtype),
+                    "all_match": all(
+                        (
+                            self.df1[column].dtype == self.df2[column].dtype,
+                            row_cnt == match_cnt,
+                        )
+                    ),
+                    "max_diff": max_diff,
+                    "null_diff": null_diff,
+                }
+            )
+
+    def all_columns_match(self) -> bool:
+        """Whether the columns all match in the dataframes"""
+        return self.df1_unq_columns() == self.df2_unq_columns() == set()
+
+    def all_rows_overlap(self) -> bool:
+        """Whether the rows are all present in both dataframes
+
+        Returns
+        -------
+        bool
+            True if all rows in df1 are in df2 and vice versa (based on
+            existence for join option)
+        """
+        return len(self.df1_unq_rows) == len(self.df2_unq_rows) == 0
+
+    def count_matching_rows(self) -> int:
+        """Count the number of rows match (on overlapping fields)
+
+        Returns
+        -------
+        int
+            Number of matching rows
+        """
+        match_columns = []
+        for column in self.intersect_columns():
+            if column not in self.join_columns:
+                match_columns.append(column + "_match")
+
+        if len(match_columns) > 0:
+            return int(
+                self.intersect_rows[match_columns]
+                .select(pl.all_horizontal(match_columns).alias("__sum"))
+                .sum()
+                .item()
+            )
+        else:
+            # corner case where it is just the join columns that make the dataframes
+            if len(self.intersect_rows) > 0:
+                return len(self.intersect_rows)
+            else:
+                return 0
+
+    def intersect_rows_match(self) -> bool:
+        """Check whether the intersect rows all match"""
+        actual_length = self.intersect_rows.shape[0]
+        return self.count_matching_rows() == actual_length
+
+    def matches(self, ignore_extra_columns: bool = False) -> bool:
+        """Return True or False if the dataframes match.
+
+        Parameters
+        ----------
+        ignore_extra_columns : bool
+            Ignores any columns in one dataframe and not in the other.
+
+        Returns
+        -------
+        bool
+            True or False if the dataframes match.
+        """
+        if not ignore_extra_columns and not self.all_columns_match():
+            return False
+        elif not self.all_rows_overlap():
+            return False
+        elif not self.intersect_rows_match():
+            return False
+        else:
+            return True
+
+    def subset(self) -> bool:
+        """Return True if dataframe 2 is a subset of dataframe 1.
+
+        Dataframe 2 is considered a subset if all of its columns are in
+        dataframe 1, and all of its rows match rows in dataframe 1 for the
+        shared columns.
+
+        Returns
+        -------
+        bool
+            True if dataframe 2 is a subset of dataframe 1.
+        """
+        if not self.df2_unq_columns() == set():
+            return False
+        elif not len(self.df2_unq_rows) == 0:
+            return False
+        elif not self.intersect_rows_match():
+            return False
+        else:
+            return True
+
+    def sample_mismatch(
+        self, column: str, sample_count: int = 10, for_display: bool = False
+    ) -> "pl.DataFrame":
+        """Returns a sample sub-dataframe which contains the identifying
+        columns, and df1 and df2 versions of the column.
+
+        Parameters
+        ----------
+        column : str
+            The raw column name (i.e. without ``_df1`` appended)
+        sample_count : int, optional
+            The number of sample records to return.  Defaults to 10.
+        for_display : bool, optional
+            Whether this is just going to be used for display (overwrite the
+            column names)
+
+        Returns
+        -------
+        Polars.DataFrame
+            A sample of the intersection dataframe, containing only the
+            "pertinent" columns, for rows that don't match on the provided
+            column.
+        """
+        row_cnt = self.intersect_rows.shape[0]
+        col_match = self.intersect_rows[column + "_match"]
+        match_cnt = col_match.sum()
+        sample_count = min(sample_count, row_cnt - match_cnt)  # type: ignore
+        sample = self.intersect_rows.filter(pl.col(column + "_match") != True).sample(
+            sample_count
+        )
+        return_cols = self.join_columns + [column + "_df1", column + "_df2"]
+        to_return = sample[return_cols]
+        if for_display:
+            to_return.columns = self.join_columns + [
+                column + " (" + self.df1_name + ")",
+                column + " (" + self.df2_name + ")",
+            ]
+        return to_return
+
+    def all_mismatch(self, ignore_matching_cols: bool = False) -> "pl.DataFrame":
+        """All rows with any columns that have a mismatch. Returns all df1 and df2 versions of the columns and join
+        columns.
+
+        Parameters
+        ----------
+        ignore_matching_cols : bool, optional
+            Whether showing the matching columns in the output or not. The default is False.
+
+        Returns
+        -------
+        Polars.DataFrame
+            All rows of the intersection dataframe, containing any columns, that don't match.
+        """
+        match_list = []
+        return_list = []
+        for col in self.intersect_rows.columns:
+            if col.endswith("_match"):
+                orig_col_name = col[:-6]
+
+                col_comparison = columns_equal(
+                    self.intersect_rows[orig_col_name + "_df1"],
+                    self.intersect_rows[orig_col_name + "_df2"],
+                    self.rel_tol,
+                    self.abs_tol,
+                    self.ignore_spaces,
+                    self.ignore_case,
+                )
+
+                if not ignore_matching_cols or (
+                    ignore_matching_cols and not col_comparison.all()
+                ):
+                    LOG.debug(f"Adding column {orig_col_name} to the result.")
+                    match_list.append(col)
+                    return_list.extend([orig_col_name + "_df1", orig_col_name + "_df2"])
+                elif ignore_matching_cols:
+                    LOG.debug(
+                        f"Column {orig_col_name} is equal in df1 and df2. It will not be added to the result."
+                    )
+        return (
+            self.intersect_rows.with_columns(__all=pl.all_horizontal(match_list))
+            .filter(pl.col("__all") != True)
+            .select(self.join_columns + return_list)
+        )
+
+    def report(
+        self,
+        sample_count: int = 10,
+        column_count: int = 10,
+        html_file: Optional[str] = None,
+    ) -> str:
+        """Returns a string representation of a report.  The representation can
+        then be printed or saved to a file.
+
+        Parameters
+        ----------
+        sample_count : int, optional
+            The number of sample records to return.  Defaults to 10.
+
+        column_count : int, optional
+            The number of columns to display in the sample records output.  Defaults to 10.
+
+        html_file : str, optional
+            HTML file name to save report output to. If ``None`` the file creation will be skipped.
+
+        Returns
+        -------
+        str
+            The report, formatted kinda nicely.
+        """
+
+        def df_to_str(pdf: "pl.DataFrame") -> str:
+            return pdf.to_pandas().to_string()
+
+        # Header
+        report = render("header.txt")
+        df_header = pl.DataFrame(
+            {
+                "DataFrame": [self.df1_name, self.df2_name],
+                "Columns": [self.df1.shape[1], self.df2.shape[1]],
+                "Rows": [self.df1.shape[0], self.df2.shape[0]],
+            }
+        )
+        report += df_to_str(df_header[["DataFrame", "Columns", "Rows"]])
+        report += "\n\n"
+
+        # Column Summary
+        report += render(
+            "column_summary.txt",
+            len(self.intersect_columns()),
+            len(self.df1_unq_columns()),
+            len(self.df2_unq_columns()),
+            self.df1_name,
+            self.df2_name,
+        )
+
+        # Row Summary
+        match_on = ", ".join(self.join_columns)
+        report += render(
+            "row_summary.txt",
+            match_on,
+            self.abs_tol,
+            self.rel_tol,
+            self.intersect_rows.shape[0],
+            self.df1_unq_rows.shape[0],
+            self.df2_unq_rows.shape[0],
+            self.intersect_rows.shape[0] - self.count_matching_rows(),
+            self.count_matching_rows(),
+            self.df1_name,
+            self.df2_name,
+            "Yes" if self._any_dupes else "No",
+        )
+
+        # Column Matching
+        cnt_intersect = self.intersect_rows.shape[0]
+        report += render(
+            "column_comparison.txt",
+            len([col for col in self.column_stats if col["unequal_cnt"] > 0]),
+            len([col for col in self.column_stats if col["unequal_cnt"] == 0]),
+            sum([col["unequal_cnt"] for col in self.column_stats]),
+        )
+
+        match_stats = []
+        match_sample = []
+        any_mismatch = False
+        for column in self.column_stats:
+            if not column["all_match"]:
+                any_mismatch = True
+                match_stats.append(
+                    {
+                        "Column": column["column"],
+                        f"{self.df1_name} dtype": column["dtype1"],
+                        f"{self.df2_name} dtype": column["dtype2"],
+                        "# Unequal": column["unequal_cnt"],
+                        "Max Diff": column["max_diff"],
+                        "# Null Diff": column["null_diff"],
+                    }
+                )
+                if column["unequal_cnt"] > 0:
+                    match_sample.append(
+                        self.sample_mismatch(
+                            column["column"], sample_count, for_display=True
+                        )
+                    )
+
+        if any_mismatch:
+            report += "Columns with Unequal Values or Types\n"
+            report += "------------------------------------\n"
+            report += "\n"
+            df_match_stats = pl.DataFrame(match_stats)
+            df_match_stats = df_match_stats.sort("Column")
+            # Have to specify again for sorting
+            report += (
+                df_match_stats[
+                    [
+                        "Column",
+                        f"{self.df1_name} dtype",
+                        f"{self.df2_name} dtype",
+                        "# Unequal",
+                        "Max Diff",
+                        "# Null Diff",
+                    ]
+                ]
+                .to_pandas()
+                .to_string()
+            )
+            report += "\n\n"
+
+            if sample_count > 0:
+                report += "Sample Rows with Unequal Values\n"
+                report += "-------------------------------\n"
+                report += "\n"
+                for sample in match_sample:
+                    report += df_to_str(sample)
+                    report += "\n\n"
+
+        if min(sample_count, self.df1_unq_rows.shape[0]) > 0:
+            report += (
+                f"Sample Rows Only in {self.df1_name} (First {column_count} Columns)\n"
+            )
+            report += (
+                f"---------------------------------------{'-' * len(self.df1_name)}\n"
+            )
+            report += "\n"
+            columns = self.df1_unq_rows.columns[:column_count]
+            unq_count = min(sample_count, self.df1_unq_rows.shape[0])
+            report += df_to_str(self.df1_unq_rows.sample(unq_count)[columns])
+            report += "\n\n"
+
+        if min(sample_count, self.df2_unq_rows.shape[0]) > 0:
+            report += (
+                f"Sample Rows Only in {self.df2_name} (First {column_count} Columns)\n"
+            )
+            report += (
+                f"---------------------------------------{'-' * len(self.df2_name)}\n"
+            )
+            report += "\n"
+            columns = self.df2_unq_rows.columns[:column_count]
+            unq_count = min(sample_count, self.df2_unq_rows.shape[0])
+            report += df_to_str(self.df2_unq_rows.sample(unq_count)[columns])
+            report += "\n\n"
+
+        if html_file:
+            html_report = report.replace("\n", "<br>").replace(" ", "&nbsp;")
+            html_report = f"<pre>{html_report}</pre>"
+            with open(html_file, "w") as f:
+                f.write(html_report)
+
+        return report
+
+
+def render(filename: str, *fields: Union[int, float, str]) -> str:
+    """Renders out an individual template.  This basically just reads in a
+    template file, and applies ``.format()`` on the fields.
+
+    Parameters
+    ----------
+    filename : str
+        The file that contains the template.  Will automagically prepend the
+        templates directory before opening
+    fields : list
+        Fields to be rendered out in the template
+
+    Returns
+    -------
+    str
+        The fully rendered out file.
+    """
+    this_dir = os.path.dirname(os.path.realpath(__file__))
+    with open(os.path.join(this_dir, "templates", filename)) as file_open:
+        return file_open.read().format(*fields)
+
+
+def columns_equal(
+    col_1: "pl.Series",
+    col_2: "pl.Series",
+    rel_tol: float = 0,
+    abs_tol: float = 0,
+    ignore_spaces: bool = False,
+    ignore_case: bool = False,
+) -> "pl.Series":
+    """Compares two columns from a dataframe, returning a True/False series,
+    with the same index as column 1.
+
+    - Two nulls (np.nan) will evaluate to True.
+    - A null and a non-null value will evaluate to False.
+    - Numeric values will use the relative and absolute tolerances.
+    - Decimal values (decimal.Decimal) will attempt to be converted to floats
+      before comparing
+    - Non-numeric values (i.e. where np.isclose can't be used) will just
+      trigger True on two nulls or exact matches.
+
+    Parameters
+    ----------
+    col_1 : Polars.Series
+        The first column to look at
+    col_2 : Polars.Series
+        The second column
+    rel_tol : float, optional
+        Relative tolerance
+    abs_tol : float, optional
+        Absolute tolerance
+    ignore_spaces : bool, optional
+        Flag to strip whitespace (including newlines) from string columns
+    ignore_case : bool, optional
+        Flag to ignore the case of string columns
+
+    Returns
+    -------
+    Polars.Series
+        A series of Boolean values.  True == the values match, False == the
+        values don't match.
+    """
+    compare: pl.Series
+    try:
+        compare = pl.Series(
+            np.isclose(col_1, col_2, rtol=rel_tol, atol=abs_tol, equal_nan=True)
+        )
+    except TypeError:
+        try:
+            if col_1.dtype in DATE_TYPE or col_2 in DATE_TYPE:
+                raise TypeError("Found date, moving to alternative logic")
+
+            compare = pl.Series(
+                np.isclose(
+                    col_1.cast(pl.Float64, strict=True),
+                    col_2.cast(pl.Float64, strict=True),
+                    rtol=rel_tol,
+                    atol=abs_tol,
+                    equal_nan=True,
+                )
+            )
+        except (ValueError, TypeError, InvalidOperationError, ComputeError):
+            try:
+                if ignore_spaces:
+                    if str(col_1.dtype) in STRING_TYPE:
+                        col_1 = col_1.str.strip_chars()
+                    if str(col_2.dtype) in STRING_TYPE:
+                        col_2 = col_2.str.strip_chars()
+
+                if ignore_case:
+                    if str(col_1.dtype) in STRING_TYPE:
+                        col_1 = col_1.str.to_uppercase()
+                    if str(col_2.dtype) in STRING_TYPE:
+                        col_2 = col_2.str.to_uppercase()
+
+                if (
+                    str(col_1.dtype) in STRING_TYPE and str(col_2.dtype) in DATE_TYPE
+                ) or (
+                    str(col_1.dtype) in DATE_TYPE and str(col_2.dtype) in STRING_TYPE
+                ):
+                    compare = compare_string_and_date_columns(col_1, col_2)
+                else:
+                    compare = pl.Series(
+                        (col_1.eq_missing(col_2)) | (col_1.is_null() & col_2.is_null())
+                    )
+            except:
+                # Blanket exception should just return all False
+                compare = pl.Series(False * col_1.shape[0])
+    return compare
+
+
+def compare_string_and_date_columns(
+    col_1: "pl.Series", col_2: "pl.Series"
+) -> "pl.Series":
+    """Compare a string column and date column, value-wise.  This tries to
+    convert a string column to a date column and compare that way.
+
+    Parameters
+    ----------
+    col_1 : Polars.Series
+        The first column to look at
+    col_2 : Polars.Series
+        The second column
+
+    Returns
+    -------
+    Polars.Series
+        A series of Boolean values.  True == the values match, False == the
+        values don't match.
+    """
+    if str(col_1.dtype) in STRING_TYPE:
+        str_column = col_1
+        date_column = col_2
+    else:
+        str_column = col_2
+        date_column = col_1
+
+    try:  # datetime is inferred
+        return pl.Series(
+            (str_column.str.to_datetime().eq_missing(date_column))
+            | (str_column.is_null() & date_column.is_null())
+        )
+    except:
+        return pl.Series([False] * col_1.shape[0])
+
+
+def get_merged_columns(
+    original_df: "pl.DataFrame", merged_df: "pl.DataFrame", suffix: str
+) -> List[str]:
+    """Gets the columns from an original dataframe, in the new merged dataframe
+
+    Parameters
+    ----------
+    original_df : Polars.DataFrame
+        The original, pre-merge dataframe
+    merged_df : Polars.DataFrame
+        Post-merge with another dataframe, with suffixes added in.
+    suffix : str
+        What suffix was used to distinguish when the original dataframe was
+        overlapping with the other merged dataframe.
+    """
+    columns = []
+    for col in original_df.columns:
+        if col in merged_df.columns:
+            columns.append(col)
+        elif col + suffix in merged_df.columns:
+            columns.append(col + suffix)
+        else:
+            raise ValueError("Column not found: %s", col)
+    return columns
+
+
+def temp_column_name(*dataframes: "pl.DataFrame") -> str:
+    """Gets a temp column name that isn't included in columns of any dataframes
+
+    Parameters
+    ----------
+    dataframes : list of Polars.DataFrame
+        The DataFrames to create a temporary column name for
+
+    Returns
+    -------
+    str
+        String column name that looks like '_temp_x' for some integer x
+    """
+    i = 0
+    while True:
+        temp_column = f"_temp_{i}"
+        unique = True
+        for dataframe in dataframes:
+            if temp_column in dataframe.columns:
+                i += 1
+                unique = False
+        if unique:
+            return temp_column
+
+
+def calculate_max_diff(col_1: "pl.Series", col_2: "pl.Series") -> float:
+    """Get a maximum difference between two columns
+
+    Parameters
+    ----------
+    col_1 : Polars.Series
+        The first column
+    col_2 : Polars.Series
+        The second column
+
+    Returns
+    -------
+    Numeric
+        Numeric field, or zero.
+    """
+    try:
+        return cast(
+            float, (col_1.cast(pl.Float64) - col_2.cast(pl.Float64)).abs().max()
+        )
+    except:
+        return 0.0
+
+
+def generate_id_within_group(
+    dataframe: "pl.DataFrame", join_columns: List[str]
+) -> "pl.Series":
+    """Generate an ID column that can be used to deduplicate identical rows.  The series generated
+    is the order within a unique group, and it handles nulls.
+
+    Parameters
+    ----------
+    dataframe : Polars.DataFrame
+        The dataframe to operate on
+    join_columns : list
+        List of strings which are the join columns
+
+    Returns
+    -------
+    Polars.Series
+        The ID column that's unique in each group.
+    """
+    default_value = "DATACOMPY_NULL"
+    if (
+        dataframe.select(pl.any_horizontal(pl.col(join_columns).is_null()))
+        .to_series()
+        .any()
+    ):
+        if (
+            dataframe.select(
+                pl.any_horizontal(pl.col(join_columns).cast(pl.String) == default_value)
+            )
+            .to_series()
+            .any()
+        ):
+            raise ValueError(f"{default_value} was found in your join columns")
+        return (
+            dataframe[join_columns]
+            .cast(pl.String)
+            .fill_null(default_value)
+            .select(rn=pl.col(dataframe.columns[0]).cum_count().over(join_columns))
+            .to_series()
+        )
+    else:
+        return dataframe.select(
+            rn=pl.col(dataframe.columns[0]).cum_count().over(join_columns)
+        ).to_series()
diff --git a/datacompy/spark.py b/datacompy/spark.py
index 53599bd0..16bf6695 100644
--- a/datacompy/spark.py
+++ b/datacompy/spark.py
@@ -16,7 +16,7 @@
 import sys
 from enum import Enum
 from itertools import chain
-from typing import Any, TextIO, List, Union, Tuple, Optional, Dict, Set
+from typing import Any, Dict, List, Optional, Set, TextIO, Tuple, Union
 
 try:
     import pyspark
diff --git a/docs/source/index.rst b/docs/source/index.rst
index bcb00f66..0ac03d6d 100644
--- a/docs/source/index.rst
+++ b/docs/source/index.rst
@@ -11,6 +11,7 @@ Contents
     Installation <install>
     Pandas Usage <pandas_usage>
     Spark Usage <spark_usage>
+    Polars Usage <polars_usage>
     Fugue Usage <fugue_usage>
     Developer Instructions <developer_instructions>
 
diff --git a/docs/source/install.rst b/docs/source/install.rst
index 4d1e798f..e6038f73 100644
--- a/docs/source/install.rst
+++ b/docs/source/install.rst
@@ -22,8 +22,8 @@ conda (installs dependencies from Conda Forge)
 
 ::
 
-    conda create --name test python=3.9
-    source activate test
+    conda create --name datacompy python=3.9 pip conda
+    source activate datacompy
     conda config --add channels conda-forge
     conda install datacompy
 
diff --git a/docs/source/pandas_usage.rst b/docs/source/pandas_usage.rst
index 1762ee9c..8c1e62f9 100644
--- a/docs/source/pandas_usage.rst
+++ b/docs/source/pandas_usage.rst
@@ -196,6 +196,9 @@ There are a few convenience methods available after the comparison has been run:
     print(compare.df2_unq_columns())
     # set()
 
+
+.. _pandas-dup-rows:
+
 Duplicate rows
 --------------
 
@@ -244,6 +247,8 @@ ID, before dropping the temp_id again.  So the first two rows in the first dataf
 first two rows in the second dataframe, and the third row in the second dataframe will be recognized
 as uniquely in the second.
 
+.. _pandas-caveats:
+
 Caveats
 +++++++
 
@@ -257,6 +262,8 @@ Caveats
   directly on that field.  If there are a lot of duplicates you may need to join on more columns, or
   handle them separately.
 
+.. _pandas-limitations:
+
 Limitations
 -----------
 
diff --git a/docs/source/polars_usage.rst b/docs/source/polars_usage.rst
new file mode 100644
index 00000000..13bb719a
--- /dev/null
+++ b/docs/source/polars_usage.rst
@@ -0,0 +1,209 @@
+Polars Usage
+============
+
+.. important::
+
+    Please note that Polars support is experimental and new in ``datacompy``
+    as of v0.11.0
+
+Overview
+--------
+
+`Polars <https://github.com/pola-rs/polars>`_ is a DataFrame interface on top of an OLAP Query Engine implemented in
+Rust using Apache Arrow Columnar Format as the memory model. DataComPy's implementation of Polars is very similar port
+of the Pandas version. There are some differences you should be aware of as they may yield slightly different
+results. For instance Polars does not have indexes like Pandas so that functionality is not supported.
+
+
+Basic Usage
+-----------
+
+Usage is very similar to the Pandas implementation. Consider the following code:
+
+.. code-block:: python
+
+    from io import StringIO
+    import polars as pl
+    from datacompy import PolarsCompare
+
+    data1 = """acct_id,dollar_amt,name,float_fld,date_fld
+    10000001234,123.45,George Maharis,14530.1555,2017-01-01
+    10000001235,0.45,Michael Bluth,1,2017-01-01
+    10000001236,1345,George Bluth,,2017-01-01
+    10000001237,123456,Bob Loblaw,345.12,2017-01-01
+    10000001238,1.05,Lucille Bluth,,2017-01-01
+    10000001238,1.05,Loose Seal Bluth,,2017-01-01
+    """
+
+    data2 = """acct_id,dollar_amt,name,float_fld
+    10000001234,123.4,George Michael Bluth,14530.155
+    10000001235,0.45,Michael Bluth,
+    10000001236,1345,George Bluth,1
+    10000001237,123456,Robert Loblaw,345.12
+    10000001238,1.05,Loose Seal Bluth,111
+    """
+
+    df1 = pl.read_csv(StringIO(data1))
+    df2 = pl.read_csv(StringIO(data2))
+
+Compare Object Setup
+--------------------
+
+Unlike the Pandas implementation there is only one supported method for joining your dataframes: join column(s).
+
+.. code-block:: python
+
+    compare = PolarsCompare(
+        df1,
+        df2,
+        join_columns='acct_id',  #You can also specify a list of columns
+        abs_tol=0.0001,
+        rel_tol=0,
+        df1_name='original',
+        df2_name='new')
+
+    # OR
+
+    compare = PolarsCompare(df1, df2, join_columns=['acct_id', 'name'])
+
+Reports
+-------
+
+A report is generated by calling ``PolarsCompare.report()``, which returns a string.
+Here is a sample report generated by ``datacompy`` for the two tables above,
+joined on ``acct_id`` (Note: if you don't specify ``df1_name`` and/or ``df2_name``,
+then any instance of "original" or "new" in the report is replaced with "df1"
+and/or "df2".)::
+
+    DataComPy Comparison
+    --------------------
+
+    DataFrame Summary
+    -----------------
+
+      DataFrame  Columns  Rows
+    0  original        5     6
+    1       new        4     5
+
+    Column Summary
+    --------------
+
+    Number of columns in common: 4
+    Number of columns in original but not in new: 1
+    Number of columns in new but not in original: 0
+
+    Row Summary
+    -----------
+
+    Matched on: acct_id
+    Any duplicates on match values: Yes
+    Absolute Tolerance: 0.0001
+    Relative Tolerance: 0
+    Number of rows in common: 5
+    Number of rows in original but not in new: 1
+    Number of rows in new but not in original: 0
+
+    Number of rows with some compared columns unequal: 5
+    Number of rows with all compared columns equal: 0
+
+    Column Comparison
+    -----------------
+
+    Number of columns compared with some values unequal: 3
+    Number of columns compared with all values equal: 1
+    Total number of values which compare unequal: 8
+
+    Columns with Unequal Values or Types
+    ------------------------------------
+
+           Column original dtype new dtype  # Unequal  Max Diff  # Null Diff
+    0  dollar_amt        Float64   Float64          1    0.0500            0
+    1   float_fld        Float64   Float64          4    0.0005            3
+    2        name         String    String          3    0.0000            0
+
+    Sample Rows with Unequal Values
+    -------------------------------
+
+           acct_id  dollar_amt (original)  dollar_amt (new)
+    0  10000001234                 123.45             123.4
+
+           acct_id name (original)            name (new)
+    0  10000001234  George Maharis  George Michael Bluth
+    1  10000001237      Bob Loblaw         Robert Loblaw
+    2  10000001238   Lucille Bluth      Loose Seal Bluth
+
+           acct_id  float_fld (original)  float_fld (new)
+    0  10000001234            14530.1555        14530.155
+    1  10000001235                1.0000              NaN
+    2  10000001236                   NaN            1.000
+    3  10000001238                   NaN          111.000
+
+    Sample Rows Only in original (First 10 Columns)
+    -----------------------------------------------
+
+           acct_id  dollar_amt              name  float_fld    date_fld
+    0  10000001238        1.05  Loose Seal Bluth        NaN  2017-01-01
+
+Convenience Methods
+-------------------
+
+There are a few convenience methods available after the comparison has been run:
+
+.. code-block:: python
+
+    print(compare.intersect_rows[['name_df1', 'name_df2', 'name_match']])
+    # shape: (5, 3)
+    # ┌────────────────┬──────────────────────┬────────────┐
+    # │ name_df1       ┆ name_df2             ┆ name_match │
+    # │ ---            ┆ ---                  ┆ ---        │
+    # │ str            ┆ str                  ┆ bool       │
+    # ╞════════════════╪══════════════════════╪════════════╡
+    # │ George Maharis ┆ George Michael Bluth ┆ false      │
+    # │ Michael Bluth  ┆ Michael Bluth        ┆ true       │
+    # │ George Bluth   ┆ George Bluth         ┆ true       │
+    # │ Bob Loblaw     ┆ Robert Loblaw        ┆ false      │
+    # │ Lucille Bluth  ┆ Loose Seal Bluth     ┆ false      │
+    # └────────────────┴──────────────────────┴────────────┘
+
+    print(compare.df1_unq_rows)
+    # shape: (1, 5)
+    # ┌─────────────┬────────────┬──────────────────┬───────────┬────────────┐
+    # │ acct_id     ┆ dollar_amt ┆ name             ┆ float_fld ┆ date_fld   │
+    # │ ---         ┆ ---        ┆ ---              ┆ ---       ┆ ---        │
+    # │ i64         ┆ f64        ┆ str              ┆ f64       ┆ str        │
+    # ╞═════════════╪════════════╪══════════════════╪═══════════╪════════════╡
+    # │ 10000001238 ┆ 1.05       ┆ Loose Seal Bluth ┆ null      ┆ 2017-01-01 │
+    # └─────────────┴────────────┴──────────────────┴───────────┴────────────┘
+
+    print(compare.df2_unq_rows)
+    # shape: (0, 4)
+    # ┌─────────┬────────────┬──────┬───────────┐
+    # │ acct_id ┆ dollar_amt ┆ name ┆ float_fld │
+    # │ ---     ┆ ---        ┆ ---  ┆ ---       │
+    # │ i64     ┆ f64        ┆ str  ┆ f64       │
+    # ╞═════════╪════════════╪══════╪═══════════╡
+    # └─────────┴────────────┴──────┴───────────┘
+
+    print(compare.intersect_columns())
+    # OrderedSet(['acct_id', 'dollar_amt', 'name', 'float_fld'])
+
+    print(compare.df1_unq_columns())
+    # OrderedSet(['date_fld'])
+
+    print(compare.df2_unq_columns())
+    # OrderedSet()
+
+Duplicate rows
+--------------
+
+The PolarsCompare will try and handle duplicate rows just like the Pandas version. See :ref:`pandas-dup-rows`.
+
+Caveats and Limitations
+-----------------------
+
+- Similar to Pandas the Polars version will try and be resilient to duplicate matching. See Pandas: :ref:`pandas-caveats`.
+- As mentioned above there is no indexing like in Pandas, so you must join on ``join_columns``
+- Polars ``join`` method uses ``join_nulls``. This tries to match `Pandas' behaviour <https://pandas.pydata.org/docs/reference/api/pandas.merge.html#pandas.merge>`_
+  but there might be unexpected results due to this.
+- The Polars documentation has a good section on migrating from Pandas to Polars and some of the things to consider.
+  See `Coming from Pandas <https://docs.pola.rs/user-guide/migration/pandas/>`_
\ No newline at end of file
diff --git a/docs/source/spark_usage.rst b/docs/source/spark_usage.rst
index 8a85862c..82c62722 100644
--- a/docs/source/spark_usage.rst
+++ b/docs/source/spark_usage.rst
@@ -1,11 +1,125 @@
 Spark Usage
 ===========
 
-*Under Construction*
+.. important::
+
+    With version ``v0.9.0`` SparkCompare now uses Null Safe (``<=>``) comparisons
+
+
+DataComPy's ``SparkCompare`` class will join two dataframes either on a list of join
+columns. It has the capability to map column names that may be different in each
+dataframe, including in the join columns. You are responsible for creating the
+dataframes from any source which Spark can handle and specifying a unique join
+key. If there are duplicates in either dataframe by join key, the match process
+will remove the duplicates before joining (and tell you how many duplicates were
+found).
+
+As with the Pandas-based ``Compare`` class, comparisons will be attempted even
+if dtypes don't match. Any schema differences will be reported in the output
+as well as in any mismatch reports, so that you can assess whether or not a
+type mismatch is a problem or not.
+
+The main reasons why you would choose to use ``SparkCompare`` over ``Compare``
+are that your data is too large to fit into memory, or you're comparing data
+that works well in a Spark environment, like partitioned Parquet, CSV, or JSON
+files, or Cerebro tables.
+
+
+Basic Usage
+-----------
+
+.. code-block:: python
+
+    import datetime
+    import datacompy
+    from pyspark.sql import Row
+
+    # This example assumes you have a SparkSession named "spark" in your environment, as you
+    # do when running `pyspark` from the terminal or in a Databricks notebook (Spark v2.0 and higher)
+
+    data1 = [
+        Row(acct_id=10000001234, dollar_amt=123.45, name='George Maharis', float_fld=14530.1555,
+            date_fld=datetime.date(2017, 1, 1)),
+        Row(acct_id=10000001235, dollar_amt=0.45, name='Michael Bluth', float_fld=1.0,
+            date_fld=datetime.date(2017, 1, 1)),
+        Row(acct_id=10000001236, dollar_amt=1345.0, name='George Bluth', float_fld=None,
+            date_fld=datetime.date(2017, 1, 1)),
+        Row(acct_id=10000001237, dollar_amt=123456.0, name='Bob Loblaw', float_fld=345.12,
+            date_fld=datetime.date(2017, 1, 1)),
+        Row(acct_id=10000001239, dollar_amt=1.05, name='Lucille Bluth', float_fld=None,
+            date_fld=datetime.date(2017, 1, 1))
+    ]
+
+    data2 = [
+        Row(acct_id=10000001234, dollar_amt=123.4, name='George Michael Bluth', float_fld=14530.155),
+        Row(acct_id=10000001235, dollar_amt=0.45, name='Michael Bluth', float_fld=None),
+        Row(acct_id=10000001236, dollar_amt=1345.0, name='George Bluth', float_fld=1.0),
+        Row(acct_id=10000001237, dollar_amt=123456.0, name='Robert Loblaw', float_fld=345.12),
+        Row(acct_id=10000001238, dollar_amt=1.05, name='Loose Seal Bluth', float_fld=111.0)
+    ]
+
+    base_df = spark.createDataFrame(data1)
+    compare_df = spark.createDataFrame(data2)
+
+    comparison = datacompy.SparkCompare(spark, base_df, compare_df, join_columns=['acct_id'])
+
+    # This prints out a human-readable report summarizing differences
+    comparison.report()
+
+
+Using SparkCompare on EMR or standalone Spark
+---------------------------------------------
+
+1. Set proxy variables
+2. Create a virtual environment, if desired (``virtualenv venv; source venv/bin/activate``)
+3. Pip install datacompy and requirements
+4. Ensure your SPARK_HOME environment variable is set (this is probably ``/usr/lib/spark`` but may
+   differ based on your installation)
+5. Augment your PYTHONPATH environment variable with
+   ``export PYTHONPATH=$SPARK_HOME/python/lib/py4j-0.10.4-src.zip:$SPARK_HOME/python:$PYTHONPATH``
+   (note that your version of py4j may differ depending on the version of Spark you're using)
+
+
+Using SparkCompare on Databricks
+--------------------------------
+
+1. Clone this repository locally
+2. Create a datacompy egg by running ``python setup.py bdist_egg`` from the repo root directory.
+3. From the Databricks front page, click the "Library" link under the "New" section.
+4. On the New library page:
+    a. Change source to "Upload Python Egg or PyPi"
+    b. Under "Upload Egg", Library Name should be "datacompy"
+    c. Drag the egg file in datacompy/dist/ to the "Drop library egg here to upload" box
+    d. Click the "Create Library" button
+5. Once the library has been created, from the library page (which you can find in your /Users/{login} workspace),
+   you can choose clusters to attach the library to.
+6. ``import datacompy`` in a notebook attached to the cluster that the library is attached to and enjoy!
+
+
+Performance Implications
+------------------------
+
+Spark scales incredibly well, so you can use ``SparkCompare`` to compare
+billions of rows of data, provided you spin up a big enough cluster. Still,
+joining billions of rows of data is an inherently large task, so there are a
+couple of things you may want to take into consideration when getting into the
+cliched realm of "big data":
+
+* ``SparkCompare`` will compare all columns in common in the dataframes and
+  report on the rest. If there are columns in the data that you don't care to
+  compare, use a ``select`` statement/method on the dataframe(s) to filter
+  those out. Particularly when reading from wide Parquet files, this can make
+  a huge difference when the columns you don't care about don't have to be
+  read into memory and included in the joined dataframe.
+* For large datasets, adding ``cache_intermediates=True`` to the ``SparkCompare``
+  call can help optimize performance by caching certain intermediate dataframes
+  in memory, like the de-duped version of each input dataset, or the joined
+  dataframe. Otherwise, Spark's lazy evaluation will recompute those each time
+  it needs the data in a report or as you access instance attributes. This may
+  be fine for smaller dataframes, but will be costly for larger ones. You do
+  need to ensure that you have enough free cache memory before you do this, so
+  this parameter is set to False by default.
 
-Meanwhile, see the Readme "Spark Detail" section for a usage example and comments on ``SparkCompare``. You may also
-want to checkout the :class:`datacompy.SparkCompare` API documentation, which is pretty well-documented, if I do say
-so myself.
 
 Known Differences
 -----------------
diff --git a/tests/test_polars.py b/tests/test_polars.py
new file mode 100644
index 00000000..8bf747df
--- /dev/null
+++ b/tests/test_polars.py
@@ -0,0 +1,1306 @@
+#
+# Copyright 2020 Capital One Services, LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""
+Testing out the datacompy functionality
+"""
+import io
+import logging
+import sys
+from datetime import datetime
+from decimal import Decimal
+from unittest import mock
+
+import numpy as np
+import pytest
+from pytest import raises
+
+pytest.importorskip("polars")
+
+import polars as pl
+from polars.exceptions import ComputeError, DuplicateError
+from polars.testing import assert_series_equal
+
+from datacompy import PolarsCompare
+from datacompy.polars import (
+    calculate_max_diff,
+    columns_equal,
+    generate_id_within_group,
+    temp_column_name,
+)
+
+logging.basicConfig(stream=sys.stdout, level=logging.DEBUG)
+
+
+def test_numeric_columns_equal_abs():
+    data = """a|b|expected
+1|1|True
+2|2.1|True
+3|4|False
+4|NULL|False
+NULL|4|False
+NULL|NULL|True"""
+    df = pl.read_csv(io.StringIO(data), separator="|", null_values=["NULL"])
+    actual_out = columns_equal(df["a"], df["b"], abs_tol=0.2)
+    expect_out = df["expected"]
+    assert_series_equal(expect_out, actual_out, check_names=False)
+
+
+def test_numeric_columns_equal_rel():
+    data = """a|b|expected
+1|1|True
+2|2.1|True
+3|4|False
+4|NULL|False
+NULL|4|False
+NULL|NULL|True"""
+    df = pl.read_csv(io.StringIO(data), separator="|", null_values=["NULL"])
+    actual_out = columns_equal(df["a"], df["b"], rel_tol=0.2)
+    expect_out = df["expected"]
+    assert_series_equal(expect_out, actual_out, check_names=False)
+
+
+def test_string_columns_equal():
+    data = """a|b|expected
+Hi|Hi|True
+Yo|Yo|True
+Hey|Hey |False
+résumé|resume|False
+résumé|résumé|True
+💩|💩|True
+💩|🤔|False
+" "|" "|True
+"  "|" "|False
+datacompy|DataComPy|False
+something|NULL|False
+NULL|something|False
+NULL|NULL|True"""
+    df = pl.read_csv(
+        io.StringIO(data),
+        separator="|",
+        null_values=["NULL"],
+        missing_utf8_is_empty_string=True,
+    )
+    actual_out = columns_equal(df["a"], df["b"], rel_tol=0.2)
+    expect_out = df["expected"]
+    assert_series_equal(expect_out, actual_out, check_names=False)
+
+
+def test_string_columns_equal_with_ignore_spaces():
+    data = """a|b|expected
+Hi|Hi|True
+Yo|Yo|True
+Hey|Hey |True
+résumé|resume|False
+résumé|résumé|True
+💩|💩|True
+💩|🤔|False
+" "|" "|True
+"  "|"       "|True
+datacompy|DataComPy|False
+something||False
+NULL|something|False
+NULL|NULL|True"""
+    df = pl.read_csv(
+        io.StringIO(data),
+        separator="|",
+        null_values=["NULL"],
+        missing_utf8_is_empty_string=True,
+    )
+    actual_out = columns_equal(df["a"], df["b"], rel_tol=0.2, ignore_spaces=True)
+    expect_out = df["expected"]
+    assert_series_equal(expect_out, actual_out, check_names=False)
+
+
+def test_string_columns_equal_with_ignore_spaces_and_case():
+    data = """a|b|expected
+Hi|Hi|True
+Yo|Yo|True
+Hey|Hey |True
+résumé|resume|False
+résumé|résumé|True
+💩|💩|True
+💩|🤔|False
+" "|" "|True
+"  "|"       "|True
+datacompy|DataComPy|True
+something||False
+NULL|something|False
+NULL|NULL|True"""
+    df = pl.read_csv(
+        io.StringIO(data),
+        separator="|",
+        null_values=["NULL"],
+        missing_utf8_is_empty_string=True,
+    )
+    actual_out = columns_equal(
+        df["a"], df["b"], rel_tol=0.2, ignore_spaces=True, ignore_case=True
+    )
+    expect_out = df["expected"]
+    assert_series_equal(expect_out, actual_out, check_names=False)
+
+
+def test_date_columns_equal():
+    data = """a|b|expected
+2017-01-01|2017-01-01|True
+2017-01-02|2017-01-02|True
+2017-10-01|2017-10-10|False
+2017-01-01||False
+|2017-01-01|False
+||True"""
+    df = pl.read_csv(
+        io.StringIO(data),
+        separator="|",
+        null_values=["NULL"],
+        missing_utf8_is_empty_string=True,
+    )
+    # First compare just the strings
+    actual_out = columns_equal(df["a"], df["b"], rel_tol=0.2)
+    expect_out = df["expected"]
+    assert_series_equal(expect_out, actual_out, check_names=False)
+
+    # Then compare converted to datetime objects
+    col_a = df["a"].str.to_datetime(strict=False)
+    col_b = df["b"].str.to_datetime(strict=False)
+    actual_out = columns_equal(col_a, col_b, rel_tol=0.2)
+    expect_out = df["expected"]
+    assert_series_equal(expect_out, actual_out, check_names=False)
+
+
+def test_date_columns_equal_with_ignore_spaces():
+    data = """a|b|expected
+2017-01-01|2017-01-01   |True
+2017-01-02  |2017-01-02|True
+2017-10-01  |2017-10-10   |False
+2017-01-01||False
+|2017-01-01|False
+||True"""
+    df = pl.read_csv(
+        io.StringIO(data),
+        separator="|",
+        null_values=["NULL"],
+        missing_utf8_is_empty_string=True,
+    )
+    # First compare just the strings
+    actual_out = columns_equal(df["a"], df["b"], rel_tol=0.2, ignore_spaces=True)
+    expect_out = df["expected"]
+    assert_series_equal(expect_out, actual_out, check_names=False)
+
+    # Then compare converted to datetime objects
+    col_a = df["a"].str.strip_chars().str.to_date(strict=False)
+    col_b = df["b"].str.strip_chars().str.to_date(strict=False)
+
+    actual_out = columns_equal(col_a, col_b, rel_tol=0.2, ignore_spaces=True)
+    expect_out = df["expected"]
+    assert_series_equal(expect_out, actual_out, check_names=False)
+
+
+def test_date_columns_equal_with_ignore_spaces_and_case():
+    data = """a|b|expected
+2017-01-01|2017-01-01   |True
+2017-01-02  |2017-01-02|True
+2017-10-01  |2017-10-10   |False
+2017-01-01||False
+|2017-01-01|False
+||True"""
+    df = pl.read_csv(
+        io.StringIO(data),
+        separator="|",
+        null_values=["NULL"],
+        missing_utf8_is_empty_string=True,
+    )
+    # First compare just the strings
+    actual_out = columns_equal(
+        df["a"], df["b"], rel_tol=0.2, ignore_spaces=True, ignore_case=True
+    )
+    expect_out = df["expected"]
+    assert_series_equal(expect_out, actual_out, check_names=False)
+
+    # Then compare converted to datetime objects
+    col_a = df["a"].str.strip_chars().str.to_date(strict=False)
+    col_b = df["b"].str.strip_chars().str.to_date(strict=False)
+
+    actual_out = columns_equal(col_a, col_b, rel_tol=0.2, ignore_spaces=True)
+    expect_out = df["expected"]
+    assert_series_equal(expect_out, actual_out, check_names=False)
+
+
+def test_date_columns_unequal():
+    """I want datetime fields to match with dates stored as strings"""
+    df = pl.DataFrame([{"a": "2017-01-01", "b": "2017-01-02"}, {"a": "2017-01-01"}])
+    df = df.with_columns(df["a"].str.to_date().alias("a_dt"))
+    df = df.with_columns(df["b"].str.to_date().alias("b_dt"))
+    assert columns_equal(df["a"], df["a_dt"]).all()
+    assert columns_equal(df["b"], df["b_dt"]).all()
+    assert columns_equal(df["a_dt"], df["a"]).all()
+    assert columns_equal(df["b_dt"], df["b"]).all()
+    assert not columns_equal(df["b_dt"], df["a"]).any()
+    assert not columns_equal(df["a_dt"], df["b"]).any()
+    assert not columns_equal(df["a"], df["b_dt"]).any()
+    assert not columns_equal(df["b"], df["a_dt"]).any()
+
+
+def test_bad_date_columns():
+    """If strings can't be coerced into dates then it should be false for the
+    whole column.
+    """
+    df = pl.DataFrame(
+        [{"a": "2017-01-01", "b": "2017-01-01"}, {"a": "2017-01-01", "b": "2A17-01-01"}]
+    )
+    df = df.with_columns(df["a"].str.to_date(exact=True).alias("a_dt"))
+    assert not columns_equal(df["a_dt"], df["b"]).any()
+
+
+def test_rounded_date_columns():
+    """If strings can't be coerced into dates then it should be false for the
+    whole column.
+    """
+    df = pl.DataFrame(
+        [
+            {"a": "2017-01-01", "b": "2017-01-01 00:00:00.000000", "exp": True},
+            {"a": "2017-01-01", "b": "2017-01-01 00:00:00.123456", "exp": False},
+            {"a": "2017-01-01", "b": "2017-01-01 00:00:01.000000", "exp": False},
+            {"a": "2017-01-01", "b": "2017-01-01 00:00:00", "exp": True},
+        ]
+    )
+
+    df = df.with_columns(df["a"].str.to_date().alias("a_dt"))
+    actual = columns_equal(df["a_dt"], df["b"])
+    expected = df["exp"]
+    assert_series_equal(actual, expected, check_names=False)
+
+
+def test_decimal_float_columns_equal():
+    df = pl.DataFrame(
+        [
+            {"a": Decimal("1"), "b": 1, "expected": True},
+            {"a": Decimal("1.3"), "b": 1.3, "expected": True},
+            {"a": Decimal("1.000003"), "b": 1.000003, "expected": True},
+            {"a": Decimal("1.000000004"), "b": 1.000000003, "expected": False},
+            {"a": Decimal("1.3"), "b": 1.2, "expected": False},
+            {"a": np.nan, "b": np.nan, "expected": True},
+            {"a": np.nan, "b": 1, "expected": False},
+            {"a": Decimal("1"), "b": np.nan, "expected": False},
+        ]
+    )
+    actual_out = columns_equal(df["a"], df["b"])
+    expect_out = df["expected"]
+    assert_series_equal(expect_out, actual_out, check_names=False)
+
+
+def test_decimal_float_columns_equal_rel():
+    df = pl.DataFrame(
+        [
+            {"a": Decimal("1"), "b": 1, "expected": True},
+            {"a": Decimal("1.3"), "b": 1.3, "expected": True},
+            {"a": Decimal("1.000003"), "b": 1.000003, "expected": True},
+            {"a": Decimal("1.000000004"), "b": 1.000000003, "expected": True},
+            {"a": Decimal("1.3"), "b": 1.2, "expected": False},
+            {"a": np.nan, "b": np.nan, "expected": True},
+            {"a": np.nan, "b": 1, "expected": False},
+            {"a": Decimal("1"), "b": np.nan, "expected": False},
+        ]
+    )
+    actual_out = columns_equal(df["a"], df["b"], abs_tol=0.001)
+    expect_out = df["expected"]
+    assert_series_equal(expect_out, actual_out, check_names=False)
+
+
+def test_decimal_columns_equal():
+    df = pl.DataFrame(
+        [
+            {"a": Decimal("1"), "b": Decimal("1"), "expected": True},
+            {"a": Decimal("1.3"), "b": Decimal("1.3"), "expected": True},
+            {"a": Decimal("1.000003"), "b": Decimal("1.000003"), "expected": True},
+            {
+                "a": Decimal("1.000000004"),
+                "b": Decimal("1.000000003"),
+                "expected": False,
+            },
+            {"a": Decimal("1.3"), "b": Decimal("1.2"), "expected": False},
+            {"a": np.nan, "b": np.nan, "expected": True},
+            {"a": np.nan, "b": Decimal("1"), "expected": False},
+            {"a": Decimal("1"), "b": np.nan, "expected": False},
+        ]
+    )
+    actual_out = columns_equal(df["a"], df["b"])
+    expect_out = df["expected"]
+    assert_series_equal(expect_out, actual_out, check_names=False)
+
+
+def test_decimal_columns_equal_rel():
+    df = pl.DataFrame(
+        [
+            {"a": Decimal("1"), "b": Decimal("1"), "expected": True},
+            {"a": Decimal("1.3"), "b": Decimal("1.3"), "expected": True},
+            {"a": Decimal("1.000003"), "b": Decimal("1.000003"), "expected": True},
+            {
+                "a": Decimal("1.000000004"),
+                "b": Decimal("1.000000003"),
+                "expected": True,
+            },
+            {"a": Decimal("1.3"), "b": Decimal("1.2"), "expected": False},
+            {"a": np.nan, "b": np.nan, "expected": True},
+            {"a": np.nan, "b": Decimal("1"), "expected": False},
+            {"a": Decimal("1"), "b": np.nan, "expected": False},
+        ]
+    )
+    actual_out = columns_equal(df["a"], df["b"], abs_tol=0.001)
+    expect_out = df["expected"]
+    assert_series_equal(expect_out, actual_out, check_names=False)
+
+
+def test_infinity_and_beyond():
+    df = pl.DataFrame(
+        [
+            {"a": np.inf, "b": np.inf, "expected": True},
+            {"a": -np.inf, "b": -np.inf, "expected": True},
+            {"a": -np.inf, "b": np.inf, "expected": False},
+            {"a": np.inf, "b": -np.inf, "expected": False},
+            {"a": 1, "b": 1, "expected": True},
+            {"a": 1, "b": 0, "expected": False},
+        ]
+    )
+    actual_out = columns_equal(df["a"], df["b"])
+    expect_out = df["expected"]
+    assert_series_equal(expect_out, actual_out, check_names=False)
+
+
+def test_compare_df_setter_bad():
+    df = pl.DataFrame([{"a": 1, "c": 2}, {"a": 2, "c": 2}])
+    df_same_col_names = pl.DataFrame([{"a": 1, "A": 2}, {"a": 2, "A": 2}])
+    df_dupe = pl.DataFrame([{"a": 1, "b": 2}, {"a": 1, "b": 3}])
+    with raises(TypeError, match="df1 must be a Polars DataFrame"):
+        compare = PolarsCompare("a", "a", ["a"])
+    with raises(ValueError, match="df1 must have all columns from join_columns"):
+        compare = PolarsCompare(df, df.clone(), ["b"])
+    with raises(DuplicateError, match="duplicate column names found"):
+        compare = PolarsCompare(df_same_col_names, df_same_col_names.clone(), ["a"])
+    assert (
+        PolarsCompare(df_dupe, df_dupe.clone(), ["a", "b"])
+        .df1.drop("_merge_left")
+        .equals(df_dupe)
+    )
+
+
+def test_compare_df_setter_good():
+    df1 = pl.DataFrame([{"a": 1, "b": 2}, {"a": 2, "b": 2}])
+    df2 = pl.DataFrame([{"A": 1, "B": 2}, {"A": 2, "B": 3}])
+    compare = PolarsCompare(df1, df2, ["a"])
+    assert compare.df1.drop("_merge_left").equals(df1)
+    assert compare.df2.equals(df2)
+    assert compare.join_columns == ["a"]
+    compare = PolarsCompare(df1, df2, ["A", "b"])
+    assert compare.df1.equals(df1)
+    assert compare.df2.equals(df2)
+    assert compare.join_columns == ["a", "b"]
+
+
+def test_compare_df_setter_different_cases():
+    df1 = pl.DataFrame([{"a": 1, "b": 2}, {"a": 2, "b": 2}])
+    df2 = pl.DataFrame([{"A": 1, "b": 2}, {"A": 2, "b": 3}])
+    compare = PolarsCompare(df1, df2, ["a"])
+    assert compare.df1.equals(df1)
+    assert compare.df2.equals(df2)
+
+
+def test_compare_df_setter_bad_index():
+    df = pl.DataFrame([{"a": 1, "A": 2}, {"a": 2, "A": 2}])
+    with raises(TypeError, match="df1 must be a Polars DataFrame"):
+        compare = PolarsCompare("a", "a", join_columns="a")
+    with raises(DuplicateError, match="duplicate column names found"):
+        compare = PolarsCompare(df, df.clone(), join_columns="a")
+
+
+def test_compare_df_setter_good_index():
+    df1 = pl.DataFrame([{"a": 1, "b": 2}, {"a": 2, "b": 2}])
+    df2 = pl.DataFrame([{"a": 1, "b": 2}, {"a": 2, "b": 3}])
+    compare = PolarsCompare(df1, df2, join_columns="a")
+    assert compare.df1.equals(df1)
+    assert compare.df2.equals(df2)
+
+
+def test_columns_overlap():
+    df1 = pl.DataFrame([{"a": 1, "b": 2}, {"a": 2, "b": 2}])
+    df2 = pl.DataFrame([{"a": 1, "b": 2}, {"a": 2, "b": 3}])
+    compare = PolarsCompare(df1, df2, ["a"])
+    assert compare.df1_unq_columns() == set()
+    assert compare.df2_unq_columns() == set()
+    assert compare.intersect_columns() == {"a", "b"}
+
+
+def test_columns_no_overlap():
+    df1 = pl.DataFrame([{"a": 1, "b": 2, "c": "hi"}, {"a": 2, "b": 2, "c": "yo"}])
+    df2 = pl.DataFrame([{"a": 1, "b": 2, "d": "oh"}, {"a": 2, "b": 3, "d": "ya"}])
+    compare = PolarsCompare(df1, df2, ["a"])
+    assert compare.df1_unq_columns() == {"c"}
+    assert compare.df2_unq_columns() == {"d"}
+    assert compare.intersect_columns() == {"a", "b"}
+
+
+def test_columns_maintain_order_through_set_operations():
+    df1 = pl.DataFrame(
+        [
+            (("A"), (0), (1), (2), (3), (4), (-2)),
+            (("B"), (0), (2), (2), (3), (4), (-3)),
+        ],
+        schema=["join", "f", "g", "b", "h", "a", "c"],
+    )
+    df2 = pl.DataFrame(
+        [
+            (("A"), (0), (1), (2), (-1), (4), (-3)),
+            (("B"), (1), (2), (3), (-1), (4), (-2)),
+        ],
+        schema=["join", "e", "h", "b", "a", "g", "d"],
+    )
+    compare = PolarsCompare(df1, df2, ["join"])
+    assert list(compare.df1_unq_columns()) == ["f", "c"]
+    assert list(compare.df2_unq_columns()) == ["e", "d"]
+    assert list(compare.intersect_columns()) == ["join", "g", "b", "h", "a"]
+
+
+def test_10k_rows():
+    df1 = pl.DataFrame(np.random.randint(0, 100, size=(10000, 2)), schema=["b", "c"])
+    df1 = df1.with_row_index()
+    df1.columns = ["a", "b", "c"]
+    df2 = df1.clone()
+    df2 = df2.with_columns(pl.col("b") + 0.1)
+    compare_tol = PolarsCompare(df1, df2, ["a"], abs_tol=0.2)
+    assert compare_tol.matches()
+    assert len(compare_tol.df1_unq_rows) == 0
+    assert len(compare_tol.df2_unq_rows) == 0
+    assert compare_tol.intersect_columns() == {"a", "b", "c"}
+    assert compare_tol.all_columns_match()
+    assert compare_tol.all_rows_overlap()
+    assert compare_tol.intersect_rows_match()
+
+    compare_no_tol = PolarsCompare(df1, df2, ["a"])
+    assert not compare_no_tol.matches()
+    assert len(compare_no_tol.df1_unq_rows) == 0
+    assert len(compare_no_tol.df2_unq_rows) == 0
+    assert compare_no_tol.intersect_columns() == {"a", "b", "c"}
+    assert compare_no_tol.all_columns_match()
+    assert compare_no_tol.all_rows_overlap()
+    assert not compare_no_tol.intersect_rows_match()
+
+
+def test_subset(caplog):
+    caplog.set_level(logging.DEBUG)
+    df1 = pl.DataFrame([{"a": 1, "b": 2, "c": "hi"}, {"a": 2, "b": 2, "c": "yo"}])
+    df2 = pl.DataFrame([{"a": 1, "c": "hi"}])
+    comp = PolarsCompare(df1, df2, ["a"])
+    assert comp.subset()
+    assert "Checking equality" in caplog.text
+
+
+def test_not_subset(caplog):
+    caplog.set_level(logging.INFO)
+    df1 = pl.DataFrame([{"a": 1, "b": 2, "c": "hi"}, {"a": 2, "b": 2, "c": "yo"}])
+    df2 = pl.DataFrame([{"a": 1, "b": 2, "c": "hi"}, {"a": 2, "b": 2, "c": "great"}])
+    comp = PolarsCompare(df1, df2, ["a"])
+    assert not comp.subset()
+    assert "c: 1 / 2 (50.00%) match" in caplog.text
+
+
+def test_large_subset():
+    df1 = pl.DataFrame(np.random.randint(0, 100, size=(10000, 2)), schema=["b", "c"])
+    df1 = df1.with_row_index()
+    df1.columns = ["a", "b", "c"]
+    df2 = df1[["a", "b"]].sample(50).clone()
+    comp = PolarsCompare(df1, df2, ["a"])
+    assert not comp.matches()
+    assert comp.subset()
+
+
+def test_string_joiner():
+    df1 = pl.DataFrame([{"ab": 1, "bc": 2}, {"ab": 2, "bc": 2}])
+    df2 = pl.DataFrame([{"ab": 1, "bc": 2}, {"ab": 2, "bc": 2}])
+    compare = PolarsCompare(df1, df2, "ab")
+    assert compare.matches()
+
+
+def test_float_and_string_with_joins():
+    df1 = pl.DataFrame([{"a": float("1"), "b": 2}, {"a": float("2"), "b": 2}])
+    df2 = pl.DataFrame([{"a": 1, "b": 2}, {"a": 2, "b": 2}])
+    with raises(ComputeError):
+        compare = PolarsCompare(df1, df2, "a")
+
+
+def test_decimal_with_nulls():
+    df1 = pl.DataFrame([{"a": 1, "b": Decimal("2")}, {"a": 2, "b": Decimal("2")}])
+    df2 = pl.DataFrame([{"a": 1, "b": 2}, {"a": 2, "b": 2}, {"a": 3, "b": 2}])
+    compare = PolarsCompare(df1, df2, "a")
+    assert not compare.matches()
+    assert compare.all_columns_match()
+    assert not compare.all_rows_overlap()
+    assert compare.intersect_rows_match()
+
+
+def test_strings_with_joins():
+    df1 = pl.DataFrame([{"a": "hi", "b": 2}, {"a": "bye", "b": 2}])
+    df2 = pl.DataFrame([{"a": "hi", "b": 2}, {"a": "bye", "b": 2}])
+    compare = PolarsCompare(df1, df2, "a")
+    assert compare.matches()
+    assert compare.all_columns_match()
+    assert compare.all_rows_overlap()
+    assert compare.intersect_rows_match()
+
+
+def test_temp_column_name():
+    df1 = pl.DataFrame([{"a": "hi", "b": 2}, {"a": "bye", "b": 2}])
+    df2 = pl.DataFrame(
+        [{"a": "hi", "b": 2}, {"a": "bye", "b": 2}, {"a": "back fo mo", "b": 3}]
+    )
+    actual = temp_column_name(df1, df2)
+    assert actual == "_temp_0"
+
+
+def test_temp_column_name_one_has():
+    df1 = pl.DataFrame([{"_temp_0": "hi", "b": 2}, {"_temp_0": "bye", "b": 2}])
+    df2 = pl.DataFrame(
+        [{"a": "hi", "b": 2}, {"a": "bye", "b": 2}, {"a": "back fo mo", "b": 3}]
+    )
+    actual = temp_column_name(df1, df2)
+    assert actual == "_temp_1"
+
+
+def test_temp_column_name_both_have():
+    df1 = pl.DataFrame([{"_temp_0": "hi", "b": 2}, {"_temp_0": "bye", "b": 2}])
+    df2 = pl.DataFrame(
+        [
+            {"_temp_0": "hi", "b": 2},
+            {"_temp_0": "bye", "b": 2},
+            {"a": "back fo mo", "b": 3},
+        ]
+    )
+    actual = temp_column_name(df1, df2)
+    assert actual == "_temp_1"
+
+
+def test_temp_column_name_both_have():
+    df1 = pl.DataFrame([{"_temp_0": "hi", "b": 2}, {"_temp_0": "bye", "b": 2}])
+    df2 = pl.DataFrame(
+        [
+            {"_temp_0": "hi", "b": 2},
+            {"_temp_1": "bye", "b": 2},
+            {"a": "back fo mo", "b": 3},
+        ]
+    )
+    actual = temp_column_name(df1, df2)
+    assert actual == "_temp_2"
+
+
+def test_temp_column_name_one_already():
+    df1 = pl.DataFrame([{"_temp_1": "hi", "b": 2}, {"_temp_1": "bye", "b": 2}])
+    df2 = pl.DataFrame(
+        [
+            {"_temp_1": "hi", "b": 2},
+            {"_temp_1": "bye", "b": 2},
+            {"a": "back fo mo", "b": 3},
+        ]
+    )
+    actual = temp_column_name(df1, df2)
+    assert actual == "_temp_0"
+
+
+### Duplicate testing!
+def test_simple_dupes_one_field():
+    df1 = pl.DataFrame([{"a": 1, "b": 2}, {"a": 1, "b": 2}])
+    df2 = pl.DataFrame([{"a": 1, "b": 2}, {"a": 1, "b": 2}])
+    compare = PolarsCompare(df1, df2, join_columns=["a"])
+    assert compare.matches()
+    # Just render the report to make sure it renders.
+    t = compare.report()
+
+
+def test_simple_dupes_two_fields():
+    df1 = pl.DataFrame([{"a": 1, "b": 2}, {"a": 1, "b": 2, "c": 2}])
+    df2 = pl.DataFrame([{"a": 1, "b": 2}, {"a": 1, "b": 2, "c": 2}])
+    compare = PolarsCompare(df1, df2, join_columns=["a", "b"])
+    assert compare.matches()
+    # Just render the report to make sure it renders.
+    t = compare.report()
+
+
+def test_simple_dupes_one_field_two_vals():
+    df1 = pl.DataFrame([{"a": 1, "b": 2}, {"a": 1, "b": 0}])
+    df2 = pl.DataFrame([{"a": 1, "b": 2}, {"a": 1, "b": 0}])
+    compare = PolarsCompare(df1, df2, join_columns=["a"])
+    assert compare.matches()
+    # Just render the report to make sure it renders.
+    t = compare.report()
+
+
+def test_simple_dupes_one_field_two_vals():
+    df1 = pl.DataFrame([{"a": 1, "b": 2}, {"a": 1, "b": 0}])
+    df2 = pl.DataFrame([{"a": 1, "b": 2}, {"a": 2, "b": 0}])
+    compare = PolarsCompare(df1, df2, join_columns=["a"])
+    assert not compare.matches()
+    assert len(compare.df1_unq_rows) == 1
+    assert len(compare.df2_unq_rows) == 1
+    assert len(compare.intersect_rows) == 1
+    # Just render the report to make sure it renders.
+    t = compare.report()
+
+
+def test_simple_dupes_one_field_three_to_two_vals():
+    df1 = pl.DataFrame([{"a": 1, "b": 2}, {"a": 1, "b": 0}, {"a": 1, "b": 0}])
+    df2 = pl.DataFrame([{"a": 1, "b": 2}, {"a": 1, "b": 0}])
+    compare = PolarsCompare(df1, df2, join_columns=["a"])
+    assert not compare.matches()
+    assert len(compare.df1_unq_rows) == 1
+    assert len(compare.df2_unq_rows) == 0
+    assert len(compare.intersect_rows) == 2
+    # Just render the report to make sure it renders.
+    t = compare.report()
+
+    assert "(First 1 Columns)" in compare.report(column_count=1)
+    assert "(First 2 Columns)" in compare.report(column_count=2)
+
+
+def test_dupes_from_real_data():
+    data = """acct_id,acct_sfx_num,trxn_post_dt,trxn_post_seq_num,trxn_amt,trxn_dt,debit_cr_cd,cash_adv_trxn_comn_cntry_cd,mrch_catg_cd,mrch_pstl_cd,visa_mail_phn_cd,visa_rqstd_pmt_svc_cd,mc_pmt_facilitator_idn_num
+100,0,2017-06-17,1537019,30.64,2017-06-15,D,CAN,5812,M2N5P5,,,0.0
+200,0,2017-06-24,1022477,485.32,2017-06-22,D,USA,4511,7114,7.0,1,
+100,0,2017-06-17,1537039,2.73,2017-06-16,D,CAN,5812,M4J 1M9,,,0.0
+200,0,2017-06-29,1049223,22.41,2017-06-28,D,USA,4789,21211,,A,
+100,0,2017-06-17,1537029,34.05,2017-06-16,D,CAN,5812,M4E 2C7,,,0.0
+200,0,2017-06-29,1049213,9.12,2017-06-28,D,CAN,5814,0,,,
+100,0,2017-06-19,1646426,165.21,2017-06-17,D,CAN,5411,M4M 3H9,,,0.0
+200,0,2017-06-30,1233082,28.54,2017-06-29,D,USA,4121,94105,7.0,G,
+100,0,2017-06-19,1646436,17.87,2017-06-18,D,CAN,5812,M4J 1M9,,,0.0
+200,0,2017-06-30,1233092,24.39,2017-06-29,D,USA,4121,94105,7.0,G,
+100,0,2017-06-19,1646446,5.27,2017-06-17,D,CAN,5200,M4M 3G6,,,0.0
+200,0,2017-06-30,1233102,61.8,2017-06-30,D,CAN,4121,0,,,
+100,0,2017-06-20,1607573,41.99,2017-06-19,D,CAN,5661,M4C1M9,,,0.0
+200,0,2017-07-01,1009403,2.31,2017-06-29,D,USA,5814,22102,,F,
+100,0,2017-06-20,1607553,86.88,2017-06-19,D,CAN,4812,H2R3A8,,,0.0
+200,0,2017-07-01,1009423,5.5,2017-06-29,D,USA,5812,2903,,F,
+100,0,2017-06-20,1607563,25.17,2017-06-19,D,CAN,5641,M4C 1M9,,,0.0
+200,0,2017-07-01,1009433,214.12,2017-06-29,D,USA,3640,20170,,A,
+100,0,2017-06-20,1607593,1.67,2017-06-19,D,CAN,5814,M2N 6L7,,,0.0
+200,0,2017-07-01,1009393,2.01,2017-06-29,D,USA,5814,22102,,F,"""
+    df1 = pl.read_csv(io.StringIO(data), separator=",")
+    df2 = df1.clone()
+    compare_acct = PolarsCompare(df1, df2, join_columns=["acct_id"])
+    assert compare_acct.matches()
+    compare_unq = PolarsCompare(
+        df1,
+        df2,
+        join_columns=["acct_id", "acct_sfx_num", "trxn_post_dt", "trxn_post_seq_num"],
+    )
+    assert compare_unq.matches()
+    # Just render the report to make sure it renders.
+    t = compare_acct.report()
+    r = compare_unq.report()
+
+
+def test_strings_with_joins_with_ignore_spaces():
+    df1 = pl.DataFrame([{"a": "hi", "b": " A"}, {"a": "bye", "b": "A"}])
+    df2 = pl.DataFrame([{"a": "hi", "b": "A"}, {"a": "bye", "b": "A "}])
+    compare = PolarsCompare(df1, df2, "a", ignore_spaces=False)
+    assert not compare.matches()
+    assert compare.all_columns_match()
+    assert compare.all_rows_overlap()
+    assert not compare.intersect_rows_match()
+
+    compare = PolarsCompare(df1, df2, "a", ignore_spaces=True)
+    assert compare.matches()
+    assert compare.all_columns_match()
+    assert compare.all_rows_overlap()
+    assert compare.intersect_rows_match()
+
+
+def test_strings_with_joins_with_ignore_case():
+    df1 = pl.DataFrame([{"a": "hi", "b": "a"}, {"a": "bye", "b": "A"}])
+    df2 = pl.DataFrame([{"a": "hi", "b": "A"}, {"a": "bye", "b": "a"}])
+    compare = PolarsCompare(df1, df2, "a", ignore_case=False)
+    assert not compare.matches()
+    assert compare.all_columns_match()
+    assert compare.all_rows_overlap()
+    assert not compare.intersect_rows_match()
+
+    compare = PolarsCompare(df1, df2, "a", ignore_case=True)
+    assert compare.matches()
+    assert compare.all_columns_match()
+    assert compare.all_rows_overlap()
+    assert compare.intersect_rows_match()
+
+
+def test_decimal_with_joins_with_ignore_spaces():
+    df1 = pl.DataFrame([{"a": 1, "b": " A"}, {"a": 2, "b": "A"}])
+    df2 = pl.DataFrame([{"a": 1, "b": "A"}, {"a": 2, "b": "A "}])
+    compare = PolarsCompare(df1, df2, "a", ignore_spaces=False)
+    assert not compare.matches()
+    assert compare.all_columns_match()
+    assert compare.all_rows_overlap()
+    assert not compare.intersect_rows_match()
+
+    compare = PolarsCompare(df1, df2, "a", ignore_spaces=True)
+    assert compare.matches()
+    assert compare.all_columns_match()
+    assert compare.all_rows_overlap()
+    assert compare.intersect_rows_match()
+
+
+def test_decimal_with_joins_with_ignore_case():
+    df1 = pl.DataFrame([{"a": 1, "b": "a"}, {"a": 2, "b": "A"}])
+    df2 = pl.DataFrame([{"a": 1, "b": "A"}, {"a": 2, "b": "a"}])
+    compare = PolarsCompare(df1, df2, "a", ignore_case=False)
+    assert not compare.matches()
+    assert compare.all_columns_match()
+    assert compare.all_rows_overlap()
+    assert not compare.intersect_rows_match()
+
+    compare = PolarsCompare(df1, df2, "a", ignore_case=True)
+    assert compare.matches()
+    assert compare.all_columns_match()
+    assert compare.all_rows_overlap()
+    assert compare.intersect_rows_match()
+
+
+def test_joins_with_ignore_spaces():
+    df1 = pl.DataFrame([{"a": 1, "b": " A"}, {"a": 2, "b": "A"}])
+    df2 = pl.DataFrame([{"a": 1, "b": "A"}, {"a": 2, "b": "A "}])
+    compare = PolarsCompare(df1, df2, "a", ignore_spaces=True)
+    assert compare.matches()
+    assert compare.all_columns_match()
+    assert compare.all_rows_overlap()
+    assert compare.intersect_rows_match()
+
+
+def test_joins_with_ignore_case():
+    df1 = pl.DataFrame([{"a": 1, "b": "a"}, {"a": 2, "b": "A"}])
+    df2 = pl.DataFrame([{"a": 1, "b": "A"}, {"a": 2, "b": "a"}])
+    compare = PolarsCompare(df1, df2, "a", ignore_case=True)
+    assert compare.matches()
+    assert compare.all_columns_match()
+    assert compare.all_rows_overlap()
+    assert compare.intersect_rows_match()
+
+
+def test_strings_with_ignore_spaces_and_join_columns():
+    df1 = pl.DataFrame([{"a": "hi", "b": "A"}, {"a": "bye", "b": "A"}])
+    df2 = pl.DataFrame([{"a": " hi ", "b": "A"}, {"a": " bye ", "b": "A"}])
+    compare = PolarsCompare(df1, df2, "a", ignore_spaces=False)
+    assert not compare.matches()
+    assert compare.all_columns_match()
+    assert not compare.all_rows_overlap()
+    assert compare.count_matching_rows() == 0
+
+    compare = PolarsCompare(df1, df2, "a", ignore_spaces=True)
+    assert compare.matches()
+    assert compare.all_columns_match()
+    assert compare.all_rows_overlap()
+    assert compare.intersect_rows_match()
+    assert compare.count_matching_rows() == 2
+
+
+def test_integers_with_ignore_spaces_and_join_columns():
+    df1 = pl.DataFrame([{"a": 1, "b": "A"}, {"a": 2, "b": "A"}])
+    df2 = pl.DataFrame([{"a": 1, "b": "A"}, {"a": 2, "b": "A"}])
+    compare = PolarsCompare(df1, df2, "a", ignore_spaces=False)
+    assert compare.matches()
+    assert compare.all_columns_match()
+    assert compare.all_rows_overlap()
+    assert compare.intersect_rows_match()
+    assert compare.count_matching_rows() == 2
+
+    compare = PolarsCompare(df1, df2, "a", ignore_spaces=True)
+    assert compare.matches()
+    assert compare.all_columns_match()
+    assert compare.all_rows_overlap()
+    assert compare.intersect_rows_match()
+    assert compare.count_matching_rows() == 2
+
+
+def test_sample_mismatch():
+    data1 = """acct_id,dollar_amt,name,float_fld,date_fld
+    10000001234,123.45,George Maharis,14530.1555,2017-01-01
+    10000001235,0.45,Michael Bluth,1,2017-01-01
+    10000001236,1345,George Bluth,,2017-01-01
+    10000001237,123456,Bob Loblaw,345.12,2017-01-01
+    10000001239,1.05,Lucille Bluth,,2017-01-01
+    10000001240,123.45,George Maharis,14530.1555,2017-01-02
+    """
+
+    data2 = """acct_id,dollar_amt,name,float_fld,date_fld
+    10000001234,123.4,George Michael Bluth,14530.155,
+    10000001235,0.45,Michael Bluth,,
+    10000001236,1345,George Bluth,1,
+    10000001237,123456,Robert Loblaw,345.12,
+    10000001238,1.05,Loose Seal Bluth,111,
+    10000001240,123.45,George Maharis,14530.1555,2017-01-02
+    """
+    df1 = pl.read_csv(io.StringIO(data1), separator=",")
+    df2 = pl.read_csv(io.StringIO(data2), separator=",")
+    compare = PolarsCompare(df1, df2, "acct_id")
+
+    output = compare.sample_mismatch(column="name", sample_count=1)
+    assert output.shape[0] == 1
+    assert (output["name_df1"] != output["name_df2"]).all()
+
+    output = compare.sample_mismatch(column="name", sample_count=2)
+    assert output.shape[0] == 2
+    assert (output["name_df1"] != output["name_df2"]).all()
+
+    output = compare.sample_mismatch(column="name", sample_count=3)
+    assert output.shape[0] == 2
+    assert (["name_df1"] != output["name_df2"]).all()
+
+
+def test_all_mismatch_not_ignore_matching_cols_no_cols_matching():
+    data1 = """acct_id,dollar_amt,name,float_fld,date_fld
+    10000001234,123.45,George Maharis,14530.1555,2017-01-01
+    10000001235,0.45,Michael Bluth,1,2017-01-01
+    10000001236,1345,George Bluth,,2017-01-01
+    10000001237,123456,Bob Loblaw,345.12,2017-01-01
+    10000001239,1.05,Lucille Bluth,,2017-01-01
+    10000001240,123.45,George Maharis,14530.1555,2017-01-02
+    """
+
+    data2 = """acct_id,dollar_amt,name,float_fld,date_fld
+    10000001234,123.4,George Michael Bluth,14530.155,
+    10000001235,0.45,Michael Bluth,,
+    10000001236,1345,George Bluth,1,
+    10000001237,123456,Robert Loblaw,345.12,
+    10000001238,1.05,Loose Seal Bluth,111,
+    10000001240,123.45,George Maharis,14530.1555,2017-01-02
+    """
+    df1 = pl.read_csv(io.StringIO(data1), separator=",")
+    df2 = pl.read_csv(io.StringIO(data2), separator=",")
+    compare = PolarsCompare(df1, df2, "acct_id")
+
+    output = compare.all_mismatch()
+    assert output.shape[0] == 4
+    assert output.shape[1] == 9
+
+    assert (output["name_df1"] != output["name_df2"]).sum() == 2
+    assert (~(output["name_df1"] != output["name_df2"])).sum() == 2
+
+    assert (output["dollar_amt_df1"] != output["dollar_amt_df2"]).sum() == 1
+    assert (~(output["dollar_amt_df1"] != output["dollar_amt_df2"])).sum() == 3
+
+    # need to use eq_missing
+    assert (
+        output.filter(pl.col.float_fld_df1.eq_missing(pl.col.float_fld_df2).not_())[
+            "acct_id"
+        ].count()
+        == 3
+    )
+    assert (
+        output.filter(pl.col.float_fld_df1.eq_missing(pl.col.float_fld_df2))[
+            "acct_id"
+        ].count()
+        == 1
+    )
+
+    assert (
+        output.filter(pl.col.date_fld_df1.eq_missing(pl.col.date_fld_df2).not_())[
+            "acct_id"
+        ].count()
+        == 4
+    )
+    assert (
+        output.filter(pl.col.date_fld_df1.eq_missing(pl.col.date_fld_df2))[
+            "acct_id"
+        ].count()
+        == 0
+    )
+
+
+def test_all_mismatch_not_ignore_matching_cols_some_cols_matching():
+    # Columns dollar_amt and name are matching
+    data1 = """acct_id,dollar_amt,name,float_fld,date_fld
+        10000001234,123.45,George Maharis,14530.1555,2017-01-01
+        10000001235,0.45,Michael Bluth,1,2017-01-01
+        10000001236,1345,George Bluth,,2017-01-01
+        10000001237,123456,Bob Loblaw,345.12,2017-01-01
+        10000001239,1.05,Lucille Bluth,,2017-01-01
+        10000001240,123.45,George Maharis,14530.1555,2017-01-02
+        """
+
+    data2 = """acct_id,dollar_amt,name,float_fld,date_fld
+        10000001234,123.45,George Maharis,14530.155,
+        10000001235,0.45,Michael Bluth,,
+        10000001236,1345,George Bluth,1,
+        10000001237,123456,Bob Loblaw,345.12,
+        10000001238,1.05,Lucille Bluth,111,
+        10000001240,123.45,George Maharis,14530.1555,2017-01-02
+        """
+    df1 = pl.read_csv(io.StringIO(data1), separator=",")
+    df2 = pl.read_csv(io.StringIO(data2), separator=",")
+    compare = PolarsCompare(df1, df2, "acct_id")
+
+    output = compare.all_mismatch()
+    assert output.shape[0] == 4
+    assert output.shape[1] == 9
+
+    assert (output["name_df1"] != output["name_df2"]).sum() == 0
+    assert (~(output["name_df1"] != output["name_df2"])).sum() == 4
+
+    assert (output["dollar_amt_df1"] != output["dollar_amt_df2"]).sum() == 0
+    assert (~(output["dollar_amt_df1"] != output["dollar_amt_df2"])).sum() == 4
+
+    # need to use eq_missing
+    assert (
+        output.filter(pl.col.float_fld_df1.eq_missing(pl.col.float_fld_df2).not_())[
+            "acct_id"
+        ].count()
+        == 3
+    )
+    assert (
+        output.filter(pl.col.float_fld_df1.eq_missing(pl.col.float_fld_df2))[
+            "acct_id"
+        ].count()
+        == 1
+    )
+
+    assert (
+        output.filter(pl.col.date_fld_df1.eq_missing(pl.col.date_fld_df2).not_())[
+            "acct_id"
+        ].count()
+        == 4
+    )
+    assert (
+        output.filter(pl.col.date_fld_df1.eq_missing(pl.col.date_fld_df2))[
+            "acct_id"
+        ].count()
+        == 0
+    )
+
+
+def test_all_mismatch_ignore_matching_cols_some_cols_matching_diff_rows():
+    # Case where there are rows on either dataset which don't match up.
+    # Columns dollar_amt and name are matching
+    data1 = """acct_id,dollar_amt,name,float_fld,date_fld
+    10000001234,123.45,George Maharis,14530.1555,2017-01-01
+    10000001235,0.45,Michael Bluth,1,2017-01-01
+    10000001236,1345,George Bluth,,2017-01-01
+    10000001237,123456,Bob Loblaw,345.12,2017-01-01
+    10000001239,1.05,Lucille Bluth,,2017-01-01
+    10000001240,123.45,George Maharis,14530.1555,2017-01-02
+    10000001241,1111.05,Lucille Bluth,
+    """
+
+    data2 = """acct_id,dollar_amt,name,float_fld,date_fld
+    10000001234,123.45,George Maharis,14530.155,
+    10000001235,0.45,Michael Bluth,,
+    10000001236,1345,George Bluth,1,
+    10000001237,123456,Bob Loblaw,345.12,
+    10000001238,1.05,Lucille Bluth,111,
+    """
+    df1 = pl.read_csv(io.StringIO(data1), separator=",")
+    df2 = pl.read_csv(io.StringIO(data2), separator=",")
+    compare = PolarsCompare(df1, df2, "acct_id")
+
+    output = compare.all_mismatch(ignore_matching_cols=True)
+
+    assert output.shape[0] == 4
+    assert output.shape[1] == 5
+
+    # need to use eq_missing
+    assert (
+        output.filter(pl.col.float_fld_df1.eq_missing(pl.col.float_fld_df2).not_())[
+            "acct_id"
+        ].count()
+        == 3
+    )
+    assert (
+        output.filter(pl.col.float_fld_df1.eq_missing(pl.col.float_fld_df2))[
+            "acct_id"
+        ].count()
+        == 1
+    )
+
+    assert (
+        output.filter(pl.col.date_fld_df1.eq_missing(pl.col.date_fld_df2).not_())[
+            "acct_id"
+        ].count()
+        == 4
+    )
+    assert (
+        output.filter(pl.col.date_fld_df1.eq_missing(pl.col.date_fld_df2))[
+            "acct_id"
+        ].count()
+        == 0
+    )
+
+    assert not ("name_df1" in output and "name_df2" in output)
+    assert not ("dollar_amt_df1" in output and "dollar_amt_df1" in output)
+
+
+def test_all_mismatch_ignore_matching_cols_some_cols_matching():
+    # Columns dollar_amt and name are matching
+    data1 = """acct_id,dollar_amt,name,float_fld,date_fld
+    10000001234,123.45,George Maharis,14530.1555,2017-01-01
+    10000001235,0.45,Michael Bluth,1,2017-01-01
+    10000001236,1345,George Bluth,,2017-01-01
+    10000001237,123456,Bob Loblaw,345.12,2017-01-01
+    10000001239,1.05,Lucille Bluth,,2017-01-01
+    10000001240,123.45,George Maharis,14530.1555,2017-01-02
+    """
+
+    data2 = """acct_id,dollar_amt,name,float_fld,date_fld
+    10000001234,123.45,George Maharis,14530.155,
+    10000001235,0.45,Michael Bluth,,
+    10000001236,1345,George Bluth,1,
+    10000001237,123456,Bob Loblaw,345.12,
+    10000001238,1.05,Lucille Bluth,111,
+    10000001240,123.45,George Maharis,14530.1555,2017-01-02
+    """
+    df1 = pl.read_csv(io.StringIO(data1), separator=",")
+    df2 = pl.read_csv(io.StringIO(data2), separator=",")
+    compare = PolarsCompare(df1, df2, "acct_id")
+
+    output = compare.all_mismatch(ignore_matching_cols=True)
+
+    assert output.shape[0] == 4
+    assert output.shape[1] == 5
+
+    # need to use eq_missing
+    assert (
+        output.filter(pl.col.float_fld_df1.eq_missing(pl.col.float_fld_df2).not_())[
+            "acct_id"
+        ].count()
+        == 3
+    )
+    assert (
+        output.filter(pl.col.float_fld_df1.eq_missing(pl.col.float_fld_df2))[
+            "acct_id"
+        ].count()
+        == 1
+    )
+
+    assert (
+        output.filter(pl.col.date_fld_df1.eq_missing(pl.col.date_fld_df2).not_())[
+            "acct_id"
+        ].count()
+        == 4
+    )
+    assert (
+        output.filter(pl.col.date_fld_df1.eq_missing(pl.col.date_fld_df2))[
+            "acct_id"
+        ].count()
+        == 0
+    )
+
+    assert not ("name_df1" in output and "name_df2" in output)
+    assert not ("dollar_amt_df1" in output and "dollar_amt_df1" in output)
+
+
+def test_all_mismatch_ignore_matching_cols_no_cols_matching():
+    data1 = """acct_id,dollar_amt,name,float_fld,date_fld
+    10000001234,123.45,George Maharis,14530.1555,2017-01-01
+    10000001235,0.45,Michael Bluth,1,2017-01-01
+    10000001236,1345,George Bluth,,2017-01-01
+    10000001237,123456,Bob Loblaw,345.12,2017-01-01
+    10000001239,1.05,Lucille Bluth,,2017-01-01
+    10000001240,123.45,George Maharis,14530.1555,2017-01-02
+    """
+
+    data2 = """acct_id,dollar_amt,name,float_fld,date_fld
+    10000001234,123.4,George Michael Bluth,14530.155,
+    10000001235,0.45,Michael Bluth,,
+    10000001236,1345,George Bluth,1,
+    10000001237,123456,Robert Loblaw,345.12,
+    10000001238,1.05,Loose Seal Bluth,111,
+    10000001240,123.45,George Maharis,14530.1555,2017-01-02
+    """
+    df1 = pl.read_csv(io.StringIO(data1), separator=",")
+    df2 = pl.read_csv(io.StringIO(data2), separator=",")
+    compare = PolarsCompare(df1, df2, "acct_id")
+
+    output = compare.all_mismatch()
+    assert output.shape[0] == 4
+    assert output.shape[1] == 9
+
+    assert (output["name_df1"] != output["name_df2"]).sum() == 2
+    assert (~(output["name_df1"] != output["name_df2"])).sum() == 2
+
+    assert (output["dollar_amt_df1"] != output["dollar_amt_df2"]).sum() == 1
+    assert (~(output["dollar_amt_df1"] != output["dollar_amt_df2"])).sum() == 3
+
+    # need to use eq_missing
+    assert (
+        output.filter(pl.col.float_fld_df1.eq_missing(pl.col.float_fld_df2).not_())[
+            "acct_id"
+        ].count()
+        == 3
+    )
+    assert (
+        output.filter(pl.col.float_fld_df1.eq_missing(pl.col.float_fld_df2))[
+            "acct_id"
+        ].count()
+        == 1
+    )
+
+    assert (
+        output.filter(pl.col.date_fld_df1.eq_missing(pl.col.date_fld_df2).not_())[
+            "acct_id"
+        ].count()
+        == 4
+    )
+    assert (
+        output.filter(pl.col.date_fld_df1.eq_missing(pl.col.date_fld_df2))[
+            "acct_id"
+        ].count()
+        == 0
+    )
+
+
+MAX_DIFF_DF = pl.DataFrame(
+    {
+        "base": [1, 1, 1, 1, 1],
+        "floats": [1.1, 1.1, 1.1, 1.2, 0.9],
+        "decimals": [
+            Decimal("1.1"),
+            Decimal("1.1"),
+            Decimal("1.1"),
+            Decimal("1.1"),
+            Decimal("1.1"),
+        ],
+        "null_floats": [np.nan, 1.1, 1, 1, 1],
+        "strings": ["1", "1", "1", "1.1", "1"],
+        "mixed_strings": ["1", "1", "1", "2", "some string"],
+        "infinity": [1, 1, 1, 1, np.inf],
+    }
+)
+
+
+@pytest.mark.parametrize(
+    "column,expected",
+    [
+        ("base", 0),
+        ("floats", 0.2),
+        ("decimals", 0.1),
+        ("null_floats", 0.1),
+        ("strings", 0.1),
+        ("mixed_strings", 0),
+        ("infinity", np.inf),
+    ],
+)
+def test_calculate_max_diff(column, expected):
+    assert np.isclose(
+        calculate_max_diff(MAX_DIFF_DF["base"], MAX_DIFF_DF[column]), expected
+    )
+
+
+def test_dupes_with_nulls():
+    df1 = pl.DataFrame(
+        {
+            "fld_1": [1, 2, 2, 3, 3, 4, 5, 5],
+            "fld_2": ["A", np.nan, np.nan, np.nan, np.nan, np.nan, np.nan, np.nan],
+        }
+    )
+    df2 = pl.DataFrame(
+        {"fld_1": [1, 2, 3, 4, 5], "fld_2": ["A", np.nan, np.nan, np.nan, np.nan]}
+    )
+    comp = PolarsCompare(df1, df2, join_columns=["fld_1", "fld_2"])
+    assert comp.subset()
+
+
+@pytest.mark.parametrize(
+    "dataframe,expected",
+    [
+        (pl.DataFrame({"a": [1, 2, 3], "b": [1, 2, 3]}), pl.Series([1, 1, 1])),
+        (
+            pl.DataFrame({"a": ["a", "a", "DATACOMPY_NULL"], "b": [1, 1, 2]}),
+            pl.Series([1, 2, 1]),
+        ),
+        (pl.DataFrame({"a": [-999, 2, 3], "b": [1, 2, 3]}), pl.Series([1, 1, 1])),
+        (
+            pl.DataFrame({"a": [1, np.nan, np.nan], "b": [1, 2, 2]}),
+            pl.Series([1, 1, 2]),
+        ),
+        (
+            pl.DataFrame({"a": ["1", np.nan, np.nan], "b": ["1", "2", "2"]}),
+            pl.Series([1, 1, 2]),
+        ),
+        (
+            pl.DataFrame(
+                {"a": [datetime(2018, 1, 1), np.nan, np.nan], "b": ["1", "2", "2"]}
+            ),
+            pl.Series([1, 1, 2]),
+        ),
+    ],
+)
+def test_generate_id_within_group(dataframe, expected):
+    assert (generate_id_within_group(dataframe, ["a", "b"]) == expected).all()
+
+
+@pytest.mark.parametrize(
+    "dataframe, message",
+    [
+        (
+            pl.DataFrame({"a": [1, np.nan, "DATACOMPY_NULL"], "b": [1, 2, 3]}),
+            "DATACOMPY_NULL was found in your join columns",
+        )
+    ],
+)
+def test_generate_id_within_group_valueerror(dataframe, message):
+    with raises(ValueError, match=message):
+        generate_id_within_group(dataframe, ["a", "b"])
+
+
+def test_lower():
+    """This function tests the toggle to use lower case for column names or not"""
+    # should match
+    df1 = pl.DataFrame({"a": [1, 2, 3], "b": [0, 1, 2]})
+    df2 = pl.DataFrame({"a": [1, 2, 3], "B": [0, 1, 2]})
+    compare = PolarsCompare(df1, df2, join_columns=["a"])
+    assert compare.matches()
+    # should not match
+    df1 = pl.DataFrame({"a": [1, 2, 3], "b": [0, 1, 2]})
+    df2 = pl.DataFrame({"a": [1, 2, 3], "B": [0, 1, 2]})
+    compare = PolarsCompare(df1, df2, join_columns=["a"], cast_column_names_lower=False)
+    assert not compare.matches()
+
+    # test join column
+    # should match
+    df1 = pl.DataFrame({"a": [1, 2, 3], "b": [0, 1, 2]})
+    df2 = pl.DataFrame({"A": [1, 2, 3], "B": [0, 1, 2]})
+    compare = PolarsCompare(df1, df2, join_columns=["a"])
+    assert compare.matches()
+    # should fail because "a" is not found in df2
+    df1 = pl.DataFrame({"a": [1, 2, 3], "b": [0, 1, 2]})
+    df2 = pl.DataFrame({"A": [1, 2, 3], "B": [0, 1, 2]})
+    expected_message = "df2 must have all columns from join_columns"
+    with raises(ValueError, match=expected_message):
+        compare = PolarsCompare(
+            df1, df2, join_columns=["a"], cast_column_names_lower=False
+        )
+
+
+@mock.patch("datacompy.polars.render")
+def test_save_html(mock_render):
+    df1 = pl.DataFrame([{"a": 1, "b": 2}, {"a": 1, "b": 2}])
+    df2 = pl.DataFrame([{"a": 1, "b": 2}, {"a": 1, "b": 2}])
+    compare = PolarsCompare(df1, df2, join_columns=["a"])
+
+    m = mock.mock_open()
+    with mock.patch("datacompy.polars.open", m, create=True):
+        # assert without HTML call
+        compare.report()
+        assert mock_render.call_count == 4
+        m.assert_not_called()
+
+    mock_render.reset_mock()
+    m = mock.mock_open()
+    with mock.patch("datacompy.polars.open", m, create=True):
+        # assert with HTML call
+        compare.report(html_file="test.html")
+        assert mock_render.call_count == 4
+        m.assert_called_with("test.html", "w")

From 5d422c0f94cde969e7e40e0062f9f86e7a00ba96 Mon Sep 17 00:00:00 2001
From: Faisal <faisal.dosani@pm.me>
Date: Thu, 18 Jan 2024 13:07:33 -0400
Subject: [PATCH 4/9] updating to 2024 (#261)

---
 datacompy/__init__.py                  |  2 +-
 datacompy/core.py                      |  2 +-
 datacompy/fugue.py                     |  2 +-
 datacompy/polars.py                    |  2 +-
 datacompy/spark.py                     |  2 +-
 docs/source/conf.py                    |  2 +-
 tests/test_core.py                     |  2 +-
 tests/test_fugue/test_duckdb.py        |  2 +-
 tests/test_fugue/test_fugue_helpers.py |  3 ++-
 tests/test_fugue/test_fugue_pandas.py  |  6 +++---
 tests/test_fugue/test_fugue_polars.py  |  2 +-
 tests/test_fugue/test_fugue_spark.py   | 10 +++++-----
 tests/test_polars.py                   |  2 +-
 tests/test_spark.py                    |  2 +-
 14 files changed, 21 insertions(+), 20 deletions(-)

diff --git a/datacompy/__init__.py b/datacompy/__init__.py
index 39231fc1..2231c88f 100644
--- a/datacompy/__init__.py
+++ b/datacompy/__init__.py
@@ -1,5 +1,5 @@
 #
-# Copyright 2023 Capital One Services, LLC
+# Copyright 2024 Capital One Services, LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
diff --git a/datacompy/core.py b/datacompy/core.py
index 8472ff1b..a1730768 100644
--- a/datacompy/core.py
+++ b/datacompy/core.py
@@ -1,5 +1,5 @@
 #
-# Copyright 2020 Capital One Services, LLC
+# Copyright 2024 Capital One Services, LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
diff --git a/datacompy/fugue.py b/datacompy/fugue.py
index 360cbe17..2ac4889a 100644
--- a/datacompy/fugue.py
+++ b/datacompy/fugue.py
@@ -1,5 +1,5 @@
 #
-# Copyright 2023 Capital One Services, LLC
+# Copyright 2024 Capital One Services, LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
diff --git a/datacompy/polars.py b/datacompy/polars.py
index 0ea879c9..814a7cd6 100644
--- a/datacompy/polars.py
+++ b/datacompy/polars.py
@@ -1,5 +1,5 @@
 #
-# Copyright 2020 Capital One Services, LLC
+# Copyright 2024 Capital One Services, LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
diff --git a/datacompy/spark.py b/datacompy/spark.py
index 16bf6695..45fe3419 100644
--- a/datacompy/spark.py
+++ b/datacompy/spark.py
@@ -1,5 +1,5 @@
 #
-# Copyright 2020 Capital One Services, LLC
+# Copyright 2024 Capital One Services, LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
diff --git a/docs/source/conf.py b/docs/source/conf.py
index 00407433..33c9c03b 100644
--- a/docs/source/conf.py
+++ b/docs/source/conf.py
@@ -20,7 +20,7 @@
 # -- Project information -----------------------------------------------------
 
 project = "datacompy"
-copyright = "2023, Capital One"
+copyright = "2024, Capital One"
 author = "Ian Robertson, Dan Coates, Faisal Dosani"
 
 # The full version, including alpha/beta/rc tags
diff --git a/tests/test_core.py b/tests/test_core.py
index 713d6c9a..12c204df 100644
--- a/tests/test_core.py
+++ b/tests/test_core.py
@@ -1,5 +1,5 @@
 #
-# Copyright 2020 Capital One Services, LLC
+# Copyright 2024 Capital One Services, LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
diff --git a/tests/test_fugue/test_duckdb.py b/tests/test_fugue/test_duckdb.py
index 39465f42..daed1edd 100644
--- a/tests/test_fugue/test_duckdb.py
+++ b/tests/test_fugue/test_duckdb.py
@@ -1,5 +1,5 @@
 #
-# Copyright 2020 Capital One Services, LLC
+# Copyright 2024 Capital One Services, LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
diff --git a/tests/test_fugue/test_fugue_helpers.py b/tests/test_fugue/test_fugue_helpers.py
index 2c2d56a9..cf51690f 100644
--- a/tests/test_fugue/test_fugue_helpers.py
+++ b/tests/test_fugue/test_fugue_helpers.py
@@ -1,5 +1,5 @@
 #
-# Copyright 2020 Capital One Services, LLC
+# Copyright 2024 Capital One Services, LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -14,6 +14,7 @@
 # limitations under the License.
 """One test helper for fugue reports."""
 
+
 def _compare_report(expected, actual, truncate=False):
     """Compare datacompy reports."""
     if truncate:
diff --git a/tests/test_fugue/test_fugue_pandas.py b/tests/test_fugue/test_fugue_pandas.py
index 3bacb30e..77884c2c 100644
--- a/tests/test_fugue/test_fugue_pandas.py
+++ b/tests/test_fugue/test_fugue_pandas.py
@@ -1,5 +1,5 @@
 #
-# Copyright 2023 Capital One Services, LLC
+# Copyright 2024 Capital One Services, LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -14,9 +14,11 @@
 # limitations under the License.
 """Test the fugue functionality with pandas."""
 from io import StringIO
+
 import pandas as pd
 from ordered_set import OrderedSet
 from pytest import raises
+from test_fugue_helpers import _compare_report
 
 from datacompy import (
     Compare,
@@ -28,8 +30,6 @@
     unq_columns,
 )
 
-from test_fugue_helpers import _compare_report
-
 
 def test_is_match_native(
     ref_df,
diff --git a/tests/test_fugue/test_fugue_polars.py b/tests/test_fugue/test_fugue_polars.py
index 97b88c7e..fdb2212a 100644
--- a/tests/test_fugue/test_fugue_polars.py
+++ b/tests/test_fugue/test_fugue_polars.py
@@ -1,5 +1,5 @@
 #
-# Copyright 2020 Capital One Services, LLC
+# Copyright 2024 Capital One Services, LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
diff --git a/tests/test_fugue/test_fugue_spark.py b/tests/test_fugue/test_fugue_spark.py
index 0ef86c24..99da708b 100644
--- a/tests/test_fugue/test_fugue_spark.py
+++ b/tests/test_fugue/test_fugue_spark.py
@@ -1,5 +1,5 @@
 #
-# Copyright 2020 Capital One Services, LLC
+# Copyright 2024 Capital One Services, LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -14,6 +14,10 @@
 # limitations under the License.
 """Test fugue and spark."""
 import pytest
+from ordered_set import OrderedSet
+from pytest import raises
+from test_fugue_helpers import _compare_report
+
 from datacompy import (
     Compare,
     all_columns_match,
@@ -23,10 +27,6 @@
     report,
     unq_columns,
 )
-from ordered_set import OrderedSet
-from pytest import raises
-
-from test_fugue_helpers import _compare_report
 
 pyspark = pytest.importorskip("pyspark")
 
diff --git a/tests/test_polars.py b/tests/test_polars.py
index 8bf747df..aabbcad1 100644
--- a/tests/test_polars.py
+++ b/tests/test_polars.py
@@ -1,5 +1,5 @@
 #
-# Copyright 2020 Capital One Services, LLC
+# Copyright 2024 Capital One Services, LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
diff --git a/tests/test_spark.py b/tests/test_spark.py
index 2babfb7f..488e1008 100644
--- a/tests/test_spark.py
+++ b/tests/test_spark.py
@@ -1,5 +1,5 @@
 #
-# Copyright 2020 Capital One Services, LLC
+# Copyright 2024 Capital One Services, LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.

From e105d84673712c96abd03237442cb2eceaa293f9 Mon Sep 17 00:00:00 2001
From: Faisal <faisal.dosani@pm.me>
Date: Fri, 2 Feb 2024 11:05:16 -0400
Subject: [PATCH 5/9] python 3.11 support (#263)

* adding 3.11 to actions

* bumping spark versions

* excluding spark matrix

* updating extras

* adding back exclude

* adding in python 3.12

* adding spark support matrix, remove 3.12

* adding spark support matrix, remove 3.12
---
 .github/workflows/test-package.yml | 15 +++++++++++----
 README.md                          | 16 ++++++++++++++++
 pyproject.toml                     | 10 +++++++---
 3 files changed, 34 insertions(+), 7 deletions(-)

diff --git a/.github/workflows/test-package.yml b/.github/workflows/test-package.yml
index b5ec2ea2..a8390f0e 100644
--- a/.github/workflows/test-package.yml
+++ b/.github/workflows/test-package.yml
@@ -19,8 +19,15 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: [3.8, 3.9, '3.10']
-        spark-version: [3.1.3, 3.2.3, 3.3.1, 3.4.0, 3.5.0]
+        python-version: [3.8, 3.9, '3.10', '3.11']
+        spark-version: [3.1.3, 3.2.4, 3.3.4, 3.4.2, 3.5.0]
+        exclude:
+          - python-version: '3.11'
+            spark-version: 3.1.3
+          - python-version: '3.11'
+            spark-version: 3.2.4
+          - python-version: '3.11'
+            spark-version: 3.3.4
     env:
       PYTHON_VERSION: ${{ matrix.python-version }}
       SPARK_VERSION: ${{ matrix.spark-version }}
@@ -55,7 +62,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: [3.8, 3.9, '3.10']
+        python-version: [3.8, 3.9, '3.10', '3.11']
     env:
       PYTHON_VERSION: ${{ matrix.python-version }}
 
@@ -81,7 +88,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: [3.8, 3.9, '3.10']
+        python-version: [3.8, 3.9, '3.10', '3.11']
     env:
       PYTHON_VERSION: ${{ matrix.python-version }}
 
diff --git a/README.md b/README.md
index d1be5efa..4dd0c869 100644
--- a/README.md
+++ b/README.md
@@ -38,6 +38,22 @@ pip install datacompy[ray]
 
 ```
 
+### In-scope Spark versions
+Different versions of Spark play nicely with only certain versions of Python below is a matrix of what we test with
+
+|             | Spark 3.1.3  | Spark 3.2.3 | Spark 3.3.4 | Spark 3.4.4 | Spark 3.5.0 |
+|-------------|--------------|-------------|-------------|-------------|-------------|
+| Python 3.8  | ✅           | ✅           | ✅           | ✅          | ✅          |
+| Python 3.9  | ✅           | ✅           | ✅           | ✅          | ✅          |
+| Python 3.10 | ✅           | ✅           | ✅           | ✅          | ✅          |
+| Python 3.11 | ❌           | ❌           | ❌           | ✅          | ✅          |
+| Python 3.12 | ❌           | ❌           | ❌           | ❌          | ❌          |
+
+
+:::{note}
+At the current time Python ``3.12`` is not supported by Spark and also Ray within Fugue.
+:::
+
 ## Supported backends
 
 - Pandas: ([See documentation](https://capitalone.github.io/datacompy/pandas_usage.html))
diff --git a/pyproject.toml b/pyproject.toml
index 21bcefd1..43b27c63 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -28,6 +28,7 @@ classifiers = [
     "Programming Language :: Python :: 3.8",
     "Programming Language :: Python :: 3.9",
     "Programming Language :: Python :: 3.10",
+    "Programming Language :: Python :: 3.11",
 ]
 
 dynamic = ["version"]
@@ -59,8 +60,11 @@ python-tag = "py3"
 
 [project.optional-dependencies]
 duckdb = ["fugue[duckdb]"]
-polars = ["fugue[polars]"]
-spark = ["fugue[spark]"]
+polars = ["polars"]
+spark = [
+    "pyspark>=3.1.1; python_version < '3.11'",
+    "pyspark>=3.4; python_version >= '3.11'",
+]
 dask = ["fugue[dask]"]
 ray = ["fugue[ray]"]
 docs = [
@@ -77,7 +81,7 @@ tests-spark = [
     "pytest",
     "pytest-cov",
     "pytest-spark",
-    "fugue[spark]",
+    "spark",
 ]
 qa = [
     "pre-commit",

From 16870f60b4edc187a9fe5cda0ba9efecdc8eaaf0 Mon Sep 17 00:00:00 2001
From: Mark Elliot <123787712+mark-thm@users.noreply.github.com>
Date: Tue, 20 Feb 2024 12:45:28 -0500
Subject: [PATCH 6/9] Move pandas upper bound to 2.2.0 (#265)

---
 pyproject.toml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pyproject.toml b/pyproject.toml
index 43b27c63..602cea8d 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -12,7 +12,7 @@ maintainers = [
 ]
 license = {text = "Apache Software License"}
 dependencies = [
-    "pandas<=2.0.2,>=0.25.0",
+    "pandas<=2.2.0,>=0.25.0",
     "numpy<=1.26.0,>=1.22.0",
     "ordered-set<=4.1.0,>=4.0.2",
     "fugue<=0.8.7,>=0.8.7",

From 1a9e2dcd9dfd684aee1686330667dd63efba80ea Mon Sep 17 00:00:00 2001
From: Faisal <faisal.dosani@capitalone.com>
Date: Tue, 20 Feb 2024 17:03:08 -0400
Subject: [PATCH 7/9] Edgetest fix (#266)

* updating edgetest config

* adding manual trigger for edgetest

* adding in pyspark edgetest config
---
 .github/workflows/edgetest.yml | 1 +
 README.md                      | 2 +-
 pyproject.toml                 | 3 ++-
 3 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/edgetest.yml b/.github/workflows/edgetest.yml
index b53cf46c..7e0a5524 100644
--- a/.github/workflows/edgetest.yml
+++ b/.github/workflows/edgetest.yml
@@ -5,6 +5,7 @@ name: Run edgetest
 on:
   schedule:
     - cron: '30 17 * * 5'
+  workflow_dispatch:  # allows manual dispatch
 jobs:
   edgetest:
     runs-on: ubuntu-latest
diff --git a/README.md b/README.md
index 4dd0c869..fefe447b 100644
--- a/README.md
+++ b/README.md
@@ -41,7 +41,7 @@ pip install datacompy[ray]
 ### In-scope Spark versions
 Different versions of Spark play nicely with only certain versions of Python below is a matrix of what we test with
 
-|             | Spark 3.1.3  | Spark 3.2.3 | Spark 3.3.4 | Spark 3.4.4 | Spark 3.5.0 |
+|             | Spark 3.1.3  | Spark 3.2.3 | Spark 3.3.4 | Spark 3.4.2 | Spark 3.5.0 |
 |-------------|--------------|-------------|-------------|-------------|-------------|
 | Python 3.8  | ✅           | ✅           | ✅           | ✅          | ✅          |
 | Python 3.9  | ✅           | ✅           | ✅           | ✅          | ✅          |
diff --git a/pyproject.toml b/pyproject.toml
index 602cea8d..5b2eee04 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -130,9 +130,10 @@ module = "pyarrow"
 ignore_missing_imports = true
 
 [edgetest.envs.core]
-python_version = "3.9"
+python_version = "3.10"
 conda_install = ["openjdk=8"]
 extras = ["dev"]
+deps = ["pyspark==3.4.2"]
 command = "pytest tests -m 'not integration'"
 upgrade = [
     "pandas",

From afbc2fc203deb3545a5c2f5448b22d591e97c39e Mon Sep 17 00:00:00 2001
From: Mark Elliot <123787712+mark-thm@users.noreply.github.com>
Date: Wed, 21 Feb 2024 09:43:17 -0500
Subject: [PATCH 8/9] Update numpy upper bound to 1.26.4 (#270)

---
 pyproject.toml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pyproject.toml b/pyproject.toml
index 5b2eee04..6cb436da 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -13,7 +13,7 @@ maintainers = [
 license = {text = "Apache Software License"}
 dependencies = [
     "pandas<=2.2.0,>=0.25.0",
-    "numpy<=1.26.0,>=1.22.0",
+    "numpy<=1.26.4,>=1.22.0",
     "ordered-set<=4.1.0,>=4.0.2",
     "fugue<=0.8.7,>=0.8.7",
 ]

From e1b08c398019ec35e55d784fcf87c1cbd4fd4fbc Mon Sep 17 00:00:00 2001
From: Faisal <faisal.dosani@pm.me>
Date: Wed, 21 Feb 2024 11:01:48 -0400
Subject: [PATCH 9/9] edgetest sparkfix (#269)

* moving to conda dep

* edgetest action python version

* edgetest action python version

* adding in cloudpickle

* adding in cloudpickle

* [TEMP] changing branch

* [TEMP] changing branch

* reverting some changes

* DEBUG

* DEBUG

* DEBUG

* DEBUG

* DEBUG

* DEBUG

* DEBUG

* DEBUG

* DEBUG

* DEBUG

* DEBUG

* DEBUG

* finally..it works...RIP
---
 .github/workflows/edgetest.yml | 45 +++++++++++++++++++++++++++++-----
 pyproject.toml                 |  1 -
 pytest.ini                     |  1 -
 3 files changed, 39 insertions(+), 8 deletions(-)

diff --git a/.github/workflows/edgetest.yml b/.github/workflows/edgetest.yml
index 7e0a5524..e47ca6ff 100644
--- a/.github/workflows/edgetest.yml
+++ b/.github/workflows/edgetest.yml
@@ -11,12 +11,45 @@ jobs:
     runs-on: ubuntu-latest
     name: running edgetest
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
         with:
           ref: develop
-      - id: run-edgetest
-        uses: edgetest-dev/run-edgetest-action@v1.4
+      
+      - name: Set up Python 3.10
+        uses: conda-incubator/setup-miniconda@v2
         with:
-          edgetest-flags: '-c pyproject.toml --export'
-          base-branch: 'develop'
-          skip-pr: 'false'
\ No newline at end of file
+          auto-update-conda: true
+          python-version: '3.10'
+          channels: conda-forge
+      
+      - name: Setup Java JDK
+        uses: actions/setup-java@v3
+        with:
+          java-version: '8'
+          distribution: 'adopt'
+
+      - name: Install edgetest
+        shell: bash -el {0}
+        run: |
+          conda install pip
+          conda install edgetest edgetest-conda
+          python -m pip install .[dev]
+      
+      - name: Run edgetest
+        shell: bash -el {0}
+        run: |
+          edgetest -c pyproject.toml --export
+
+      - name: Create Pull Request
+        uses: peter-evans/create-pull-request@v3
+        with:
+          branch: edgetest-patch
+          base: develop
+          delete-branch: true
+          title: Changes by run-edgetest action
+          commit-message: '[edgetest] automated change'
+          body: Automated changes by [run-edgetest-action](https://github.com/edgetest-dev/run-edgetest-action) GitHub action
+          add-paths: |
+            requirements.txt
+            setup.cfg
+            pyproject.toml
\ No newline at end of file
diff --git a/pyproject.toml b/pyproject.toml
index 6cb436da..dcf8d5c9 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -133,7 +133,6 @@ ignore_missing_imports = true
 python_version = "3.10"
 conda_install = ["openjdk=8"]
 extras = ["dev"]
-deps = ["pyspark==3.4.2"]
 command = "pytest tests -m 'not integration'"
 upgrade = [
     "pandas",
diff --git a/pytest.ini b/pytest.ini
index 3036b87b..c780335c 100644
--- a/pytest.ini
+++ b/pytest.ini
@@ -6,5 +6,4 @@ spark_options =
   spark.default.parallelism: 4
   spark.executor.cores: 4
   spark.sql.execution.arrow.pyspark.enabled: true
-  spark.sql.execution.arrow.enabled: false
   spark.sql.adaptive.enabled: false
\ No newline at end of file