Allow variable neutralization in YAML test files

CHANGELOG.md

@@ -1,5 +1,12 @@
 # Changelog
 
+## 35.12.0 [#1021](https://github.com/openfisca/openfisca-core/pull/1021)
+
+#### New features
+
+- Introduce `neutralize_variables` option in YAML test files
+  - A neutralized variable in a YAML test will return its default value when computed.
+
 ## 35.11.0 [#1149](https://github.com/openfisca/openfisca-core/pull/1149)
 
 #### New Features

openfisca_core/tools/test_runner.py

@@ -31,7 +31,30 @@ def import_yaml():
     return yaml, Loader
 
 
-TEST_KEYWORDS = {'absolute_error_margin', 'description', 'extensions', 'ignore_variables', 'input', 'keywords', 'max_spiral_loops', 'name', 'only_variables', 'output', 'period', 'reforms', 'relative_error_margin'}
+#: These keys the syntax keys for writing YAML tests.
+#:
+#: .. seealso::
+#:      For more information on common keys and examples, please take a look at
+#:      the official documentation on `Writing YAML tests`_.
+#:
+#: .. _Writing YAML tests: https://openfisca.org/doc/coding-the-legislation/writing_yaml_tests.html
+#:
+TEST_KEYWORDS = {
+    'absolute_error_margin',
+    'description',
+    'extensions',
+    'ignore_variables',
+    'input',
+    'keywords',
+    'max_spiral_loops',
+    'name',
+    'neutralize_variables',
+    'only_variables',
+    'output',
+    'period',
+    'reforms',
+    'relative_error_margin'
+    }
 
 yaml, Loader = import_yaml()
 
@@ -137,7 +160,12 @@ def runtest(self):
             unexpected_keys = set(self.test.keys()).difference(TEST_KEYWORDS)
             raise ValueError("Unexpected keys {} in test '{}' in file '{}'".format(unexpected_keys, self.name, self.fspath))
 
-        self.tax_benefit_system = _get_tax_benefit_system(self.baseline_tax_benefit_system, self.test.get('reforms', []), self.test.get('extensions', []))
+        self.tax_benefit_system = _get_tax_benefit_system(
+            self.baseline_tax_benefit_system,
+            self.test.get('reforms', []),
+            self.test.get('extensions', []),
+            self.test.get('neutralize_variables', [])
+            )
 
         builder = SimulationBuilder()
         input = self.test.get('input', {})
@@ -283,14 +311,16 @@ def pytest_collect_file(self, parent, path):
                 options = self.options)
 
 
-def _get_tax_benefit_system(baseline, reforms, extensions):
+def _get_tax_benefit_system(baseline, reforms, extensions, neutralize_variables):
     if not isinstance(reforms, list):
         reforms = [reforms]
     if not isinstance(extensions, list):
         extensions = [extensions]
+    if not isinstance(neutralize_variables, list):
+        neutralize_variables = [neutralize_variables]
 
     # keep reforms order in cache, ignore extensions order
-    key = hash((id(baseline), ':'.join(reforms), frozenset(extensions)))
+    key = hash((id(baseline), ':'.join(reforms), frozenset(extensions), ':'.join(neutralize_variables)))
     if _tax_benefit_system_cache.get(key):
         return _tax_benefit_system_cache.get(key)
 
@@ -303,6 +333,9 @@ def _get_tax_benefit_system(baseline, reforms, extensions):
         current_tax_benefit_system = current_tax_benefit_system.clone()
         current_tax_benefit_system.load_extension(extension)
 
+    for neutralized_variable in neutralize_variables:
+        current_tax_benefit_system.neutralize_variable(neutralized_variable)
+
     _tax_benefit_system_cache[key] = current_tax_benefit_system
 
     return current_tax_benefit_system

setup.py

@@ -48,7 +48,7 @@
 
 setup(
     name = 'OpenFisca-Core',
-    version = '35.11.0',
+    version = '35.12.0',
     author = 'OpenFisca Team',
     author_email = 'contact@openfisca.org',
     classifiers = [

tests/core/test_yaml.py

@@ -64,6 +64,10 @@ def test_with_anchors(tax_benefit_system):
     assert run_yaml_test(tax_benefit_system, 'test_with_anchors.yaml') == EXIT_OK
 
 
+def test_with_neutralized_variables(tax_benefit_system):
+    assert run_yaml_test(tax_benefit_system, 'test_with_neutralized_variables.yaml') == EXIT_OK
+
+
 def test_run_tests_from_directory_fail(tax_benefit_system):
     assert run_yaml_test(tax_benefit_system, yaml_tests_dir) == EXIT_TESTSFAILED
 

tests/core/tools/test_runner/test_yaml_runner.py

@@ -27,6 +27,9 @@ def apply_reform(self, path):
     def load_extension(self, extension):
         pass
 
+    def neutralize_variable(self, variable_name):
+        pass
+
     def entities_by_singular(self):
         return {}
 
@@ -95,51 +98,62 @@ def test_variable_not_found():
 def test_tax_benefit_systems_with_reform_cache():
     baseline = TaxBenefitSystem()
 
-    ab_tax_benefit_system = _get_tax_benefit_system(baseline, 'ab', [])
-    ba_tax_benefit_system = _get_tax_benefit_system(baseline, 'ba', [])
+    ab_tax_benefit_system = _get_tax_benefit_system(baseline, 'ab', [], [])
+    ba_tax_benefit_system = _get_tax_benefit_system(baseline, 'ba', [], [])
     assert ab_tax_benefit_system != ba_tax_benefit_system
 
 
 def test_reforms_formats():
     baseline = TaxBenefitSystem()
 
-    lonely_reform_tbs = _get_tax_benefit_system(baseline, 'lonely_reform', [])
-    list_lonely_reform_tbs = _get_tax_benefit_system(baseline, ['lonely_reform'], [])
+    lonely_reform_tbs = _get_tax_benefit_system(baseline, 'lonely_reform', [], [])
+    list_lonely_reform_tbs = _get_tax_benefit_system(baseline, ['lonely_reform'], [], [])
     assert lonely_reform_tbs == list_lonely_reform_tbs
 
 
 def test_reforms_order():
     baseline = TaxBenefitSystem()
 
-    abba_tax_benefit_system = _get_tax_benefit_system(baseline, ['ab', 'ba'], [])
-    baab_tax_benefit_system = _get_tax_benefit_system(baseline, ['ba', 'ab'], [])
+    abba_tax_benefit_system = _get_tax_benefit_system(baseline, ['ab', 'ba'], [], [])
+    baab_tax_benefit_system = _get_tax_benefit_system(baseline, ['ba', 'ab'], [], [])
     assert abba_tax_benefit_system != baab_tax_benefit_system  # keep reforms order in cache
 
 
 def test_tax_benefit_systems_with_extensions_cache():
     baseline = TaxBenefitSystem()
 
-    xy_tax_benefit_system = _get_tax_benefit_system(baseline, [], 'xy')
-    yx_tax_benefit_system = _get_tax_benefit_system(baseline, [], 'yx')
+    xy_tax_benefit_system = _get_tax_benefit_system(baseline, [], 'xy', [])
+    yx_tax_benefit_system = _get_tax_benefit_system(baseline, [], 'yx', [])
     assert xy_tax_benefit_system != yx_tax_benefit_system
 
 
 def test_extensions_formats():
     baseline = TaxBenefitSystem()
 
-    lonely_extension_tbs = _get_tax_benefit_system(baseline, [], 'lonely_extension')
-    list_lonely_extension_tbs = _get_tax_benefit_system(baseline, [], ['lonely_extension'])
+    lonely_extension_tbs = _get_tax_benefit_system(baseline, [], 'lonely_extension', [])
+    list_lonely_extension_tbs = _get_tax_benefit_system(baseline, [], ['lonely_extension'], [])
     assert lonely_extension_tbs == list_lonely_extension_tbs
 
 
 def test_extensions_order():
     baseline = TaxBenefitSystem()
 
-    xy_tax_benefit_system = _get_tax_benefit_system(baseline, [], ['x', 'y'])
-    yx_tax_benefit_system = _get_tax_benefit_system(baseline, [], ['y', 'x'])
+    xy_tax_benefit_system = _get_tax_benefit_system(baseline, [], ['x', 'y'], [])
+    yx_tax_benefit_system = _get_tax_benefit_system(baseline, [], ['y', 'x'], [])
     assert xy_tax_benefit_system == yx_tax_benefit_system  # extensions order is ignored in cache
 
 
+def test_tax_benefit_systems_with_neutralized_variables():
+    baseline = TaxBenefitSystem()
+
+    re_tax_benefit_system = _get_tax_benefit_system(baseline, 'r', ['e'], [])
+    ren_tax_benefit_system = _get_tax_benefit_system(baseline, 'r', ['e'], ['n'])
+    n_tax_benefit_system = _get_tax_benefit_system(baseline, [], [], ['n'])
+
+    assert re_tax_benefit_system != ren_tax_benefit_system
+    assert ren_tax_benefit_system != n_tax_benefit_system
+
+
 def test_performance_graph_option_output():
     test = {'input': {'salary': {'2017-01': 2000}}, 'output': {'salary': {'2017-01': 2000}}}
     test_item = TestItem(test)

tests/fixtures/yaml_tests/test_with_neutralized_variables.yaml

@@ -0,0 +1,17 @@
+- name: "Result outside neutralized variables"
+  period: 2021-01
+  neutralize_variables:
+    - housing_allowance
+  input:
+    age: 30
+  output:
+    basic_income: 600
+
+- name: "Result within neutralized variables"
+  period: 2021-01
+  neutralize_variables:
+    - basic_income
+  input:
+    age: 30
+  output:
+    basic_income: 0