[dev]: Replace mypy with ty (experimental) (#573)

* [dev]: Replace mypy with ty (experimental)

* Fix ruff+ty conflicts

Author: amureki

.github/workflows/ci.yml

@@ -18,7 +18,7 @@ jobs:
         lint-command:
           - ruff check --output-format=github .
           - black --check --diff .
-          - mypy model_bakery
+          - ty check model_bakery
     steps:
       - uses: actions/checkout@v6
       - name: Install uv

CHANGELOG.md

@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 ### Added
 
 ### Changed
+- [dev] Replace mypy with ty as the primary type checker with stricter type checks
 
 ### Removed
 

Makefile

@@ -12,6 +12,6 @@ release:
 lint:
 	@black .
 	@ruff check .
-	@mypy model_bakery
+	@ty check model_bakery
 
 .PHONY: help test release lint

model_bakery/baker.py

@@ -719,7 +719,7 @@ def _handle_m2m(self, instance: Model):
                         m2m_relation.source_field_name: instance,
                         m2m_relation.target_field_name: value,
                     }
-                    make(
+                    make(  # ty: ignore[no-matching-overload]
                         cast(type[Model], through_model),
                         _using=self._using,
                         **base_kwargs,

model_bakery/generators.py

@@ -43,13 +43,13 @@
     # PostgreSQL-specific field (only available when psycopg is installed)
     from django.contrib.postgres.fields import ArrayField
 except ImportError:
-    ArrayField = None
+    ArrayField = None  # type: ignore[misc,assignment]
 
 try:
     # PostgreSQL-specific field (only available when psycopg is installed)
     from django.contrib.postgres.fields import HStoreField
 except ImportError:
-    HStoreField = None
+    HStoreField = None  # type: ignore[misc,assignment]
 
 try:
     # PostgreSQL-specific fields (only available when psycopg is installed)
@@ -59,9 +59,9 @@
         CITextField,
     )
 except ImportError:
-    CICharField = None
-    CIEmailField = None
-    CITextField = None
+    CICharField = None  # type: ignore[misc,assignment]
+    CIEmailField = None  # type: ignore[misc,assignment]
+    CITextField = None  # type: ignore[misc,assignment]
 
 
 try:
@@ -74,11 +74,11 @@
         IntegerRangeField,
     )
 except ImportError:
-    BigIntegerRangeField = None
-    DateRangeField = None
-    DateTimeRangeField = None
-    DecimalRangeField = None
-    IntegerRangeField = None
+    BigIntegerRangeField = None  # type: ignore[misc,assignment]
+    DateRangeField = None  # type: ignore[misc,assignment]
+    DateTimeRangeField = None  # type: ignore[misc,assignment]
+    DecimalRangeField = None  # type: ignore[misc,assignment]
+    IntegerRangeField = None  # type: ignore[misc,assignment]
 
 
 default_mapping = {

model_bakery/random_gen.py

@@ -515,9 +515,11 @@ def gen_pg_numbers_range(number_cast: Callable[[int], Any]) -> Callable:
 
     def gen_range():
         try:
-            from psycopg.types.range import Range
+            from psycopg.types.range import Range  # ty: ignore[unresolved-import]
         except ImportError:
-            from psycopg2._range import NumericRange as Range
+            from psycopg2._range import (  # ty: ignore[unresolved-import]
+                NumericRange as Range,
+            )
 
         base_num = baker_random.randint(1, 100000)
         return Range(number_cast(-1 * base_num), number_cast(base_num))
@@ -533,9 +535,9 @@ def gen_date_range():
     to avoid empty ranges in tests.
     """
     try:
-        from psycopg.types.range import DateRange
+        from psycopg.types.range import DateRange  # ty: ignore[unresolved-import]
     except ImportError:
-        from psycopg2.extras import DateRange
+        from psycopg2.extras import DateRange  # ty: ignore[unresolved-import]
 
     base_date = gen_date()
     interval = gen_interval(min_interval=24 * 60 * 60 * 1000)
@@ -551,9 +553,13 @@ def gen_datetime_range():
     to avoid empty ranges in tests.
     """
     try:
-        from psycopg.types.range import TimestamptzRange
+        from psycopg.types.range import (  # ty: ignore[unresolved-import]
+            TimestamptzRange,
+        )
     except ImportError:
-        from psycopg2.extras import DateTimeTZRange as TimestamptzRange
+        from psycopg2.extras import (  # ty: ignore[unresolved-import]
+            DateTimeTZRange as TimestamptzRange,
+        )
 
     base_datetime = gen_datetime()
     interval = gen_interval(min_interval=24 * 60 * 60 * 1000)

model_bakery/recipe.py

@@ -5,12 +5,9 @@
     Any,
     Generic,
     TypeVar,
-    cast,
     overload,
 )
 
-from django.db.models import Model
-
 from . import baker
 from ._types import M
 from .exceptions import RecipeNotFound
@@ -178,19 +175,19 @@ def extend(self: _T, **attrs: Any) -> _T:
         return type(self)(self._model, **attr_mapping)
 
 
-def _load_recipe_from_calling_module(recipe: str) -> Recipe[Model]:
+def _load_recipe_from_calling_module(recipe_name: str) -> Recipe[Any]:
     """Load `Recipe` from the string attribute given from the calling module.
 
     Args:
-        recipe (str): the name of the recipe attribute within the module from
+        recipe_name (str): the name of the recipe attribute within the module from
             which it should be loaded
 
     Returns:
         (Recipe): recipe resolved from calling module
     """
-    recipe = getattr(get_calling_module(2), recipe)
+    recipe = getattr(get_calling_module(2), recipe_name)
     if recipe:
-        return cast(Recipe[Model], recipe)
+        return recipe
     else:
         raise RecipeNotFound
 
@@ -217,16 +214,19 @@ def foreign_key(
     This resolves recipes supplied as strings from other module paths or from
     the calling code's module.
     """
+    resolved_recipe: Recipe[M]
     if isinstance(recipe, str):
         # Load `Recipe` from string before handing off to `RecipeForeignKey`
         try:
             # Try to load from another module
-            recipe = baker._recipe(recipe)
+            resolved_recipe = baker._recipe(recipe)
         except (AttributeError, ImportError, ValueError):
             # Probably not in another module, so load it from calling module
-            recipe = _load_recipe_from_calling_module(cast(str, recipe))
+            resolved_recipe = _load_recipe_from_calling_module(recipe)
+    else:
+        resolved_recipe = recipe
 
-    return RecipeForeignKey(cast(Recipe[M], recipe), one_to_one)
+    return RecipeForeignKey(resolved_recipe, one_to_one)
 
 
 class related(Generic[M]):  # FIXME

pyproject.toml

@@ -59,7 +59,7 @@ dev = [
     "pytest-django",
     "black",
     "ruff",
-    "mypy",
+    "ty",
 ]
 
 [project.urls]
@@ -84,9 +84,14 @@ source = [
 [tool.coverage.report]
 show_missing = true
 
-[tool.mypy]
-ignore_missing_imports = true
-disallow_untyped_calls = true
+[tool.ty.rules]
+# Django dynamic attributes (.objects, ._meta, etc.)
+# TODO: remove these two ignores when ty adds better Django support
+#  https://github.com/astral-sh/ty/issues/1018
+unresolved-attribute = "ignore"
+possibly-missing-attribute = "ignore"
+# Allow `# type: ignore` comments (mypy syntax) without warnings
+unused-ignore-comment = "ignore"
 
 [tool.pytest.ini_options]
 addopts = "--tb=short -rxs --nomigrations"