Feat/allow re-exports in __init__.py files

CHANGELOG.md

@@ -21,6 +21,7 @@ Semantic versioning in our case means:
 
 ### Features
 
+- Allows `__init__.py` files that consist only of imports, #3486
 - Adds `--max-conditions` option, #3493
 
 ### Misc

tests/test_visitors/test_ast/test_modules/test_empty_init.py

@@ -24,6 +24,7 @@
 from two import two_func
 """
 
+module_with_multiple_statements = 'x = 1\ny = 2'
 module_with_logic = """
 try:
     import some_module
@@ -40,6 +41,8 @@
         empty_module,
         module_with_docstring,
         module_with_comments,
+        module_with_imports,
+        module_with_one_import,
     ],
 )
 def test_init_without_logic(
@@ -64,9 +67,8 @@ def test_init_without_logic(
 @pytest.mark.parametrize(
     'code',
     [
-        module_with_imports,
-        module_with_one_import,
         module_with_logic,
+        module_with_multiple_statements,
     ],
 )
 def test_init_with_logic(

wemake_python_styleguide/violations/best_practices.py

@@ -452,6 +452,7 @@ class InitModuleHasLogicViolation(SimpleViolation):
 
     1. comments, since they are dropped before AST comes in play
     2. docstrings are used sometimes when required to state something
+    3. imports and re-exports to define a public module API
 
     It is also fine when you have different users that use your code.
     And you do not want to break everything for them.

wemake_python_styleguide/visitors/ast/modules.py

@@ -48,6 +48,13 @@ def _check_init_contents(self, node: ast.Module) -> None:
         if not self._is_init() or not node.body:
             return
 
+        only_imports = all(
+            isinstance(statement, (ast.Import, ast.ImportFrom))
+            for statement in node.body
+        )
+        if only_imports:
+            return
+
         if len(node.body) > 1:
             self.add_violation(InitModuleHasLogicViolation())
             return