run mypy during tests

.github/workflows/tests.yaml

@@ -29,6 +29,7 @@ jobs:
           - {name: '3.8', python: '3.8', tox: py38}
           - {name: '3.7', python: '3.7', tox: py37}
           - {name: 'PyPy 3.9', python: 'pypy3.9', tox: pypy39}
+          - {name: 'Typing', python: '3.10', os: ubuntu-latest, tox: typing}
     steps:
       - uses: actions/checkout@v3
       - uses: actions/setup-python@v4

requirements/dev.in

@@ -1,5 +1,6 @@
 -r docs.in
 -r tests.in
+-r typing.in
 pip-compile-multi
 pre-commit
 tox

requirements/dev.txt

@@ -1,4 +1,4 @@
-# SHA1:54196885a2acdc154945dacc9470e2a9900fd8c1
+# SHA1:54b5b77ec8c7a0064ffa93b2fd16cb0130ba177c
 #
 # This file is autogenerated by pip-compile-multi
 # To update, run:
@@ -7,6 +7,7 @@
 #
 -r docs.txt
 -r tests.txt
+-r typing.txt
 build==0.8.0
     # via pip-tools
 cfgv==3.3.1

requirements/typing.in

@@ -0,0 +1,3 @@
+mypy
+pytest
+sqlalchemy[mypy]

requirements/typing.txt

@@ -0,0 +1,41 @@
+# SHA1:8a98a56578d312cffa4514127f5a91091f2e38d8
+#
+# This file is autogenerated by pip-compile-multi
+# To update, run:
+#
+#    pip-compile-multi
+#
+attrs==22.1.0
+    # via pytest
+greenlet==1.1.3
+    # via sqlalchemy
+iniconfig==1.1.1
+    # via pytest
+mypy==0.971
+    # via
+    #   -r requirements/typing.in
+    #   sqlalchemy
+mypy-extensions==0.4.3
+    # via mypy
+packaging==21.3
+    # via pytest
+pluggy==1.0.0
+    # via pytest
+py==1.11.0
+    # via pytest
+pyparsing==3.0.9
+    # via packaging
+pytest==7.1.3
+    # via -r requirements/typing.in
+sqlalchemy[mypy]==1.4.41
+    # via -r requirements/typing.in
+sqlalchemy2-stubs==0.0.2a27
+    # via sqlalchemy
+tomli==2.0.1
+    # via
+    #   mypy
+    #   pytest
+typing-extensions==4.3.0
+    # via
+    #   mypy
+    #   sqlalchemy2-stubs

setup.cfg

@@ -74,3 +74,17 @@ ignore =
     W503
 # up to 88 allowed by bugbear B950
 max-line-length = 80
+
+[mypy]
+python_version = 3.7
+files = src/flask_sqlalchemy, tests
+show_error_codes = true
+pretty = true
+strict = true
+# db.Model attribute doesn't recognize subclassing
+disable_error_code = name-defined
+# db.Model is Any
+disallow_subclassing_any = false
+
+[mypy-importlib_metadata.*]
+ignore_missing_imports = True

src/flask_sqlalchemy/extension.py

@@ -542,7 +542,7 @@ def _apply_driver_defaults(self, options: dict[str, t.Any], app: Flask) -> None:
         url = sa.engine.make_url(options["url"])
 
         if url.drivername in {"sqlite", "sqlite+pysqlite"}:
-            if url.database in {None, "", ":memory:"}:
+            if url.database is None or url.database in {"", ":memory:"}:
                 options["poolclass"] = sa.pool.StaticPool
 
                 if "connect_args" not in options:
@@ -558,7 +558,7 @@ def _apply_driver_defaults(self, options: dict[str, t.Any], app: Flask) -> None:
                 else:
                     db_str = url.database
 
-                if not os.path.isabs(db_str):  # type: ignore[arg-type]
+                if not os.path.isabs(db_str):
                     os.makedirs(app.instance_path, exist_ok=True)
                     db_str = os.path.join(app.instance_path, db_str)
 

src/flask_sqlalchemy/pagination.py

@@ -338,7 +338,8 @@ def _query_count(self) -> int:
         select = self._query_args["select"]
         sub = select.options(sa.orm.lazyload("*")).order_by(None).subquery()
         session = self._query_args["session"]
-        return session.execute(sa.select(sa.func.count()).select_from(sub)).scalar()
+        out = session.execute(sa.select(sa.func.count()).select_from(sub)).scalar()
+        return out  # type: ignore[no-any-return]
 
 
 class QueryPagination(Pagination):
@@ -350,8 +351,10 @@ class QueryPagination(Pagination):
 
     def _query_items(self) -> list[t.Any]:
         query = self._query_args["query"]
-        return query.limit(self.per_page).offset(self._query_offset).all()
+        out = query.limit(self.per_page).offset(self._query_offset).all()
+        return out  # type: ignore[no-any-return]
 
     def _query_count(self) -> int:
         # Query.count automatically disables eager loads
-        return self._query_args["query"].order_by(None).count()
+        out = self._query_args["query"].order_by(None).count()
+        return out  # type: ignore[no-any-return]

tests/test_engine.py

@@ -95,8 +95,9 @@ def test_sqlite_driver_level_uri(app: Flask) -> None:
     db = SQLAlchemy(app)
     db.create_all()
     db_path = db.engine.url.database
-    assert db_path.startswith(f"file:{app.instance_path}")  # type: ignore[union-attr]
-    assert os.path.exists(db_path[5:])  # type: ignore[arg-type]
+    assert db_path is not None
+    assert db_path.startswith(f"file:{app.instance_path}")
+    assert os.path.exists(db_path[5:])
 
 
 @unittest.mock.patch.object(SQLAlchemy, "_make_engine", autospec=True)

tests/test_track_modifications.py

@@ -50,15 +50,15 @@ def after_commit(sender: Flask, changes: list[tuple[t.Any, str]]) -> None:
         assert before == after
 
         db.session.remove()
-        item = db.session.get(Example, 1)
+        item = db.session.get(Example, 1)  # type: ignore[assignment]
         item.data = "test"  # type: ignore[assignment]
         db.session.commit()
         assert len(before) == 1
         assert before[0] == (item, "update")
         assert before == after
 
         db.session.remove()
-        item = db.session.get(Example, 1)
+        item = db.session.get(Example, 1)  # type: ignore[assignment]
         db.session.delete(item)
         db.session.commit()
         assert len(before) == 1

tox.ini

@@ -19,6 +19,10 @@ deps = pre-commit
 skip_install = true
 commands = pre-commit run --all-files --show-diff-on-failure
 
+[testenv:typing]
+deps = -r requirements/typing.txt
+commands = mypy
+
 [testenv:docs]
 deps = -r requirements/docs.txt
 commands = sphinx-build -W -b html -d {envtmpdir}/doctrees docs {envtmpdir}/html