typing: Make less use of ParamSpec

pyproject.toml

@@ -38,7 +38,7 @@ test = ["testscenarios", "testresources"]
 twisted = ["Twisted", "fixtures"]
 dev = [
     "ruff==0.15.8",
-    "mypy>=1.0.0",
+    "mypy>=1.20.0",
     "typing-extensions;python_version<'3.11'",
 ]
 
@@ -63,7 +63,9 @@ python_version = "3.10"
 show_column_numbers = true
 show_error_context = true
 strict = true
-warn_unused_ignores = true
+# remove this when 1.20.1 is released
+# https://github.com/python/mypy/issues/21137
+warn_unused_configs = false
 # FIXME(stephenfin): We should remove this
 implicit_reexport = true
 exclude = 'doc'

testtools/testcase.py

@@ -577,18 +577,18 @@ def assertIsInstance(  # type: ignore[override]
     def assertRaises(
         self,
         expected_exception: type[_E],
-        callable: Callable[_P, _R],
-        *args: _P.args,
-        **kwargs: _P.kwargs,
+        callable: Callable[..., Any],
+        *args: Any,
+        **kwargs: Any,
     ) -> _E: ...
 
     @overload
     def assertRaises(
         self,
         expected_exception: tuple[type[BaseException], ...],
-        callable: Callable[_P, _R],
-        *args: _P.args,
-        **kwargs: _P.kwargs,
+        callable: Callable[..., Any],
+        *args: Any,
+        **kwargs: Any,
     ) -> BaseException: ...
 
     @overload
@@ -928,7 +928,7 @@ def _validate_setup_called(result: object) -> object:
                     )
                 return result
 
-            ret.addBoth(_validate_setup_called)
+            ret.addBoth(_validate_setup_called)  # type: ignore[attr-defined]
         else:
             # Synchronous: validate immediately
             if not self.__setup_called:
@@ -964,7 +964,7 @@ def _validate_teardown_called(result: object) -> object:
                     )
                 return result
 
-            ret.addBoth(_validate_teardown_called)
+            ret.addBoth(_validate_teardown_called)  # type: ignore[attr-defined]
         else:
             # Synchronous: validate immediately
             if not self.__teardown_called:

testtools/testsuite.py

@@ -62,7 +62,7 @@ def iterate_tests(
         for test in test_suite_or_case:
             yield from iterate_tests(test)
     else:
-        yield test_suite_or_case  # type: ignore[misc]
+        yield test_suite_or_case
 
 
 class ConcurrentTestSuite(unittest.TestSuite):

tox.ini

@@ -19,6 +19,6 @@ commands =
 
 [testenv:mypy]
 deps =
-  mypy
+  mypy>=1.20.0
 commands =
   mypy --cache-dir="{envdir}/mypy_cache" {posargs:testtools}