fix: disable rename parent module imported

As per #421, this is not working currently, so I'm putting this feature behind an
experimental feature flag until it's fixed properly.

conftest.py

@@ -0,0 +1,8 @@
+import pytest
+
+
+@pytest.fixture()
+def parent_module_import_enabled(mocker):
+    yield mocker.patch(
+        "django_codemod.visitors.base.REPLACE_PARENT_MODULE_IMPORTED", True
+    )

django_codemod/feature_flags.py

@@ -0,0 +1,5 @@
+import os
+
+REPLACE_PARENT_MODULE_IMPORTED = (
+    os.getenv("EXPERIMENTAL_REPLACE_PARENT_MODULE_IMPORTED") == "1"
+)

django_codemod/visitors/base.py

@@ -22,6 +22,8 @@
 from libcst.codemod.visitors import AddImportsVisitor
 from libcst.metadata import ParentNodeProvider, Scope, ScopeProvider
 
+from django_codemod.feature_flags import REPLACE_PARENT_MODULE_IMPORTED
+
 
 class BaseDjCodemodTransformer(ContextAwareTransformer, ABC):
     deprecated_in: Tuple[int, int]
@@ -142,6 +144,8 @@ def _check_import_from_parent(
 
             from parent import module
         """
+        if not REPLACE_PARENT_MODULE_IMPORTED:
+            return None
         # First, exit early if 'import *' is used
         if isinstance(updated_node.names, ImportStar):
             return None

tests/visitors/test_base.py

@@ -60,6 +60,7 @@ def test_simple_substitution(self) -> None:
         """
         self.assertCodemod(before, after)
 
+    @pytest.mark.usefixtures("parent_module_import_enabled")
     def test_parent_module(self) -> None:
         before = """
             from django.dummy import module
@@ -87,6 +88,7 @@ def test_reference_without_call(self) -> None:
         """
         self.assertCodemod(before, after)
 
+    @pytest.mark.usefixtures("parent_module_import_enabled")
     def test_parent_reference_without_call(self) -> None:
         before = """
             from django.dummy import module
@@ -300,6 +302,7 @@ def test_simple_substitution(self) -> None:
         """
         self.assertCodemod(before, after)
 
+    @pytest.mark.usefixtures("parent_module_import_enabled")
     def test_parent_module(self) -> None:
         before = """
             from django.dummy import module
@@ -313,6 +316,7 @@ def test_parent_module(self) -> None:
         """
         self.assertCodemod(before, after)
 
+    @pytest.mark.usefixtures("parent_module_import_enabled")
     def test_parent_module_with_other(self) -> None:
         before = """
             from django.dummy import other_mod, module
@@ -327,6 +331,7 @@ def test_parent_module_with_other(self) -> None:
         """
         self.assertCodemod(before, after)
 
+    @pytest.mark.usefixtures("parent_module_import_enabled")
     def test_parent_module_import_alias(self) -> None:
         before = """
             from django.dummy import module as django_module

tests/visitors/test_models.py

@@ -1,3 +1,4 @@
+import pytest
 from parameterized import parameterized
 
 from django_codemod.visitors.models import (
@@ -369,6 +370,7 @@ class MyThing(Model):
         """
         self.assertCodemod(before, after)
 
+    @pytest.mark.usefixtures("parent_module_import_enabled")
     def test_simple_substitution(self) -> None:
         before = """
             from django.db import models

tests/visitors/test_timezone.py

@@ -75,3 +75,11 @@ def test_with_name_args(self) -> None:
         """
 
         self.assertCodemod(before, after)
+
+    def test_issue_421(self) -> None:
+        before = after = """
+        from django.utils import timezone
+
+        now = timezone.now()
+        """
+        self.assertCodemod(before, after)