Fix manager types scope (#991)

* Fix manager types scope

* Restore incremental mode and mention in developer docs

* Separate dev mypy config and regular one

* Document config files usage

.github/workflows/test.yml

@@ -46,7 +46,7 @@ jobs:
           pip install -r ./requirements.txt
 
       - name: Run tests
-        run: pytest
+        run: pytest --mypy-ini-file=mypy.ini
 
   typecheck:
     runs-on: ubuntu-latest

CONTRIBUTING.md

@@ -70,6 +70,12 @@ To execute the unit tests, simply run:
 pytest
 ```
 
+If you get some unexpected results or want to be sure that tests run is not affected by previous one, remove `mypy` cache:
+
+```bash
+rm -r .mypy_cache
+```
+
 We also test the stubs against Django's own test suite. This is done in CI but you can also do this locally.
 To execute the script run:
 

mypy.ini

@@ -1,3 +1,10 @@
+# Regular configuration file (can be used as base in other projects, runs in CI)
+
+# NOTE: this config file is not used by pytest locally.
+# See comment in mypy.ini.dev for explanation.
+
+# WARNING: when changing this file, consider doing the same with mypy.ini.dev
+
 [mypy]
 allow_redefinition = True
 check_untyped_defs = True

mypy.ini.dev

@@ -0,0 +1,30 @@
+# Configuration file to use during development
+
+# Changes of plugin code are not detected by mypy, so
+# incremental mode can be harmful during development
+# (mypy cache is not always invalidated).
+# However, incremental mode has to be supported by django-stubs,
+# thus another config (mypy.ini) is used in CI.
+# Incremental mode is recommended for regular usage.
+
+# WARNING: when changing this file, consider doing the same with mypy.ini
+
+[mypy]
+allow_redefinition = True
+check_untyped_defs = True
+ignore_missing_imports = True
+# Avoid caching between test runs
+incremental = False
+strict_optional = True
+show_traceback = True
+warn_no_return = False
+warn_unused_ignores = True
+warn_redundant_casts = True
+warn_unused_configs = True
+warn_unreachable = True
+
+plugins =
+    mypy_django_plugin.main
+
+[mypy.plugins.django-stubs]
+django_settings_module = scripts.django_tests_settings

mypy_django_plugin/lib/helpers.py

@@ -369,10 +369,9 @@ def bind_or_analyze_type(t: MypyType, api: SemanticAnalyzer, module_name: Option
     That should hopefully give a bound type."""
     if isinstance(t, UnboundType) and module_name is not None:
         node = api.lookup_fully_qualified_or_none(module_name + "." + t.name)
-        if node is None:
-            return None
+        if node is not None and node.type is not None:
             return node.type
-    else:
+
     return api.anal_type(t)
 
 

mypy_django_plugin/transformers/models.py

@@ -212,7 +212,11 @@ class AddManagers(ModelClassInitializer):
             # replace self type with new class, if copying method
             if isinstance(sym.node, FuncDef):
                 helpers.copy_method_to_another_class(
-                    new_cls_def_context, self_type=custom_manager_type, new_method_name=name, method_node=sym.node
+                    new_cls_def_context,
+                    self_type=custom_manager_type,
+                    new_method_name=name,
+                    method_node=sym.node,
+                    original_module_name=base_manager_info.module_name,
                 )
                 continue
 

pytest.ini

@@ -7,5 +7,5 @@ addopts =
     -s
     -v
     --cache-clear
-    --mypy-ini-file=./mypy.ini
+    --mypy-ini-file=./mypy.ini.dev
     --mypy-extension-hook=scripts.tests_extension_hook.django_plugin_hook

tests/typecheck/managers/test_managers.yml

@@ -423,3 +423,22 @@
                 class MyModel(models.Model):
 
                    objects = MyModelManager()
+
+-   case: regression_manager_scope_foreign
+    main: |
+        from myapp.models import MyModel
+        reveal_type(MyModel.on_site)  # N: Revealed type is "myapp.models.MyModel_CurrentSiteManager[myapp.models.MyModel]"
+    installed_apps:
+        - myapp
+        - django.contrib.sites
+    files:
+        -   path: myapp/__init__.py
+        -   path: myapp/models.py
+            content: |
+                from django.db import models
+                from django.contrib.sites.models import Site
+                from django.contrib.sites.managers import CurrentSiteManager
+
+                class MyModel(models.Model):
+                    site = models.ForeignKey(Site, on_delete=models.CASCADE)
+                    on_site = CurrentSiteManager()