Stricter mypy (#2325)

{{cookiecutter.project_name}}/pyproject.toml

@@ -51,7 +51,7 @@ pytest-timeout = "^2.1"
 django-test-migrations = "^1.3"
 hypothesis = "^6.84"
 
-django-stubs = { version = "^4.2", extras = ["compatible-mypy"] }
+django-stubs = { version = "^4.2.4", extras = ["compatible-mypy"] }
 
 djlint = "^1.32"
 yamllint = "^1.32"

{{cookiecutter.project_name}}/setup.cfg

@@ -76,9 +76,6 @@ addopts =
   --fail-on-template-vars
   # Output:
   --tb=short
-  # Parallelism:
-  # -n auto
-  # --boxed
   # Coverage:
   --cov=server
   --cov=tests
@@ -115,6 +112,8 @@ enable_error_code =
   possibly-undefined,
   redundant-self,
 
+extra_checks = true
+
 allow_redefinition = false
 check_untyped_defs = true
 disallow_untyped_decorators = true
@@ -127,7 +126,6 @@ ignore_errors = false
 ignore_missing_imports = true
 implicit_reexport = false
 local_partial_types = true
-strict_concatenate = true
 strict_equality = true
 strict_optional = true
 show_error_codes = true
@@ -142,7 +140,7 @@ plugins =
   mypy_django_plugin.main
 
 [mypy-server.apps.*.migrations.*]
-# Django migrations should not produce any errors:
+# Django migrations should not produce any errors (they are tested anyway):
 ignore_errors = true
 
 [mypy.plugins.django-stubs]