feat: new exception

src/ape/exceptions.py

@@ -480,6 +480,26 @@ class ChainError(ApeException):
     """
 
 
+class ContractNotFoundError(ChainError):
+    """
+    Raised when a contract is not found at an address.
+    """
+
+    def __init__(self, address: "AddressType", has_explorer: bool, provider_name: str):
+        msg = f"Failed to get contract type for address '{address}'."
+        msg += (
+            " Contract may need verification."
+            if has_explorer
+            else (
+                f" Current provider '{provider_name}' has no associated "
+                "explorer plugin. Try installing an explorer plugin using "
+                f"{click.style(text='ape plugins install etherscan', fg='green')}, "
+                "or using a network with explorer support."
+            )
+        )
+        super().__init__(msg)
+
+
 class UnknownSnapshotError(ChainError):
     """
     Raised when given an unknown snapshot ID.

src/ape/managers/chain.py

@@ -6,7 +6,6 @@
 from pathlib import Path
 from typing import IO, Collection, Dict, Iterator, List, Optional, Set, Type, Union, cast
 
-import click
 import pandas as pd
 from ethpm_types import ContractType
 from rich import get_console
@@ -26,6 +25,7 @@
     APINotImplementedError,
     BlockNotFoundError,
     ChainError,
+    ContractNotFoundError,
     ConversionError,
     CustomError,
     ProviderNotConnectedError,
@@ -967,7 +967,12 @@ def _cache_deployment(
     def __getitem__(self, address: AddressType) -> ContractType:
         contract_type = self.get(address)
         if not contract_type:
-            raise IndexError(f"No contract type found at address '{address}'.")
+            # Create error message from custom exception cls.
+            err = ContractNotFoundError(
+                address, self.provider.network.explorer is not None, self.provider.name
+            )
+            # Must raise IndexError.
+            raise IndexError(str(err))
 
         return contract_type
 
@@ -1144,6 +1149,7 @@ def instance_at(
         Raises:
             TypeError: When passing an invalid type for the `contract_type` arguments
               (expects `ContractType`).
+            :class:`~ape.exceptions.ContractNotFoundError`: When the contract type is not found.
 
         Args:
             address (Union[str, AddressType]): The address of the plugin. If you are using the ENS
@@ -1176,17 +1182,12 @@ def instance_at(
                 raise  # Current exception
 
         if not contract_type:
-            msg = f"Failed to get contract type for address '{contract_address}'."
-            if self.provider.network.explorer is None:
-                msg += (
-                    f" Current provider '{self.provider.name}' has no associated "
-                    "explorer plugin. Try installing an explorer plugin using "
-                    f"{click.style(text='ape plugins install etherscan', fg='green')}, "
-                    "or using a network with explorer support."
-                )
-            else:
-                msg += " Contract may need verification."
-            raise ChainError(msg)
+            raise ContractNotFoundError(
+                contract_address,
+                self.provider.network.explorer is not None,
+                self.provider.name,
+            )
+
         elif not isinstance(contract_type, ContractType):
             raise TypeError(
                 f"Expected type '{ContractType.__name__}' for argument 'contract_type'."

src/ape/managers/project/manager.py

@@ -555,7 +555,7 @@ def get_contract(self, contract_name: str) -> ContractContainer:
 
         contract = self._get_contract(contract_name)
         if not contract:
-            raise ValueError(f"No contract found with name '{contract_name}'.")
+            raise ProjectError(f"No contract found with name '{contract_name}'.")
 
         return contract
 

tests/functional/test_chain.py

@@ -8,7 +8,12 @@
 
 import ape
 from ape.contracts import ContractInstance
-from ape.exceptions import APINotImplementedError, ChainError, ConversionError
+from ape.exceptions import (
+    APINotImplementedError,
+    ChainError,
+    ContractNotFoundError,
+    ConversionError,
+)
 from ape_ethereum.transactions import Receipt, TransactionStatusEnum
 from tests.conftest import skip_if_plugin_installed
 
@@ -384,6 +389,30 @@ def fn(addr, default=None):
     assert caplog.records[-1].message == expected_fail_message
 
 
+def test_instance_at_contract_type_not_found(chain):
+    new_address = "0x4a986a6dCA6dbf99bC3d17F8D71aFb0d60e740f8"
+    expected = (
+        rf"Failed to get contract type for address '{new_address}'. "
+        r"Current provider 'test' has no associated explorer plugin. "
+        "Try installing an explorer plugin using .*ape plugins install etherscan.*, "
+        r"or using a network with explorer support\."
+    )
+    with pytest.raises(ContractNotFoundError, match=expected):
+        chain.contracts.instance_at(new_address)
+
+
+def test_contracts_getitem_contract_not_found(chain):
+    new_address = "0x4a986a6dCA6dbf99bC3d17F8D71aFb0d60e740f8"
+    expected = (
+        rf"Failed to get contract type for address '{new_address}'. "
+        r"Current provider 'test' has no associated explorer plugin. "
+        "Try installing an explorer plugin using .*ape plugins install etherscan.*, "
+        r"or using a network with explorer support\."
+    )
+    with pytest.raises(IndexError, match=expected):
+        _ = chain.contracts[new_address]
+
+
 def test_deployments_mapping_cache_location(chain):
     # Arrange / Act
     mapping_location = chain.contracts._deployments_mapping_cache