Fixes #3413 (#3431)

Author: dgtrv

CHANGELOG.md

@@ -31,6 +31,7 @@ Semantic versioning in our case means:
 - Fixes `WPS115` false-positive on `StrEnum`, `IntEnum`, `IntFlag` attributes, #3381
 - Fixes `WPS432`, now it ignores magic numbers in `Literal`, #3397
 - Fixes `WPS466` for generic type specifications `MyClassDecorator[T]`, #3417
+- Fixes `WPS212` to ignore nested classes and functions when counting `return` statements, #3413
 
 Due to PEP-695, it's now allowed to use `[]` in the decorator only for `python3.12+`.
 

tests/test_visitors/test_ast/test_complexity/test_function/test_returns.py

@@ -17,19 +17,30 @@ def function():
 """
 
 function_with_nested_function_and_returns = """
-def function():  # has two returns
+def function():  # has one return and a nested function
     def factory():  # has one return
         return 1
     return factory
 """
 
+function_with_nested_class_and_returns = """
+def function():  # has one return (we do not count returns in nested objects)
+    def inner_function(x):
+        return x
+    class Factory:
+        def method(self):
+            return 1
+    return inner_function(Factory())
+"""
+
 
 @pytest.mark.parametrize(
     'code',
     [
         function_without_returns,
         function_with_returns,
         function_with_nested_function_and_returns,
+        function_with_nested_class_and_returns,
     ],
 )
 def test_returns_correct_count(
@@ -52,7 +63,6 @@ def test_returns_correct_count(
     'code',
     [
         function_with_returns,
-        function_with_nested_function_and_returns,
     ],
 )
 def test_returns_wrong_count(
@@ -72,3 +82,27 @@ def test_returns_wrong_count(
 
     assert_errors(visitor, [TooManyReturnsViolation])
     assert_error_text(visitor, '2', option_values.max_returns)
+
+
+@pytest.mark.parametrize(
+    'code',
+    [
+        function_with_nested_function_and_returns,
+        function_with_nested_class_and_returns,
+    ],
+)
+def test_returns_in_nested_objects_correct_count(
+    assert_errors,
+    parse_ast_tree,
+    options,
+    code,
+    mode,
+):
+    """Testing that returns in nested functions and classes are not counted."""
+    tree = parse_ast_tree(mode(code))
+
+    option_values = options(max_returns=1)
+    visitor = FunctionComplexityVisitor(option_values, tree=tree)
+    visitor.run()
+
+    assert_errors(visitor, [])

wemake_python_styleguide/visitors/ast/complexity/function.py

@@ -88,17 +88,8 @@ def _update_variables(
 
             function_variables.append(variable_def.id)
 
-    def _check_sub_node(
-        self,
-        node: AnyFunctionDef,
-        sub_node: ast.AST,
-    ) -> None:
-        if isinstance(sub_node, ast.Name) and isinstance(
-            sub_node.ctx,
-            ast.Store,
-        ):
-            self._update_variables(node, sub_node)
-
+    def _update_counters(self, node: AnyFunctionDef, sub_node: ast.AST) -> None:
+        """Updates statement counters for the given node."""
         error_counters: _NodeTypeHandler = {
             ast.Return: self.metrics.returns,
             ast.Expr: self.metrics.expressions,
@@ -109,8 +100,24 @@ def _check_sub_node(
 
         for types, counter in error_counters.items():
             if isinstance(sub_node, types):
+                # We do not count returns in nested functions and classes
+                if types is ast.Return and get_context(sub_node) is not node:
+                    continue
                 counter[node] += 1
 
+    def _check_sub_node(
+        self,
+        node: AnyFunctionDef,
+        sub_node: ast.AST,
+    ) -> None:
+        if isinstance(sub_node, ast.Name) and isinstance(
+            sub_node.ctx,
+            ast.Store,
+        ):
+            self._update_variables(node, sub_node)
+
+        self._update_counters(node, sub_node)
+
 
 @final
 @alias(