run_mypy: avoid type-checking tools against every possible python version

run_mypy.py

@@ -69,7 +69,8 @@ modules = [
     'mesonbuild/mtest.py',
     'mesonbuild/optinterpreter.py',
     'mesonbuild/programs.py',
-
+]
+additional = [
     'run_mypy.py',
     'run_project_tests.py',
     'run_single_test.py',
@@ -115,23 +116,29 @@ def main() -> int:
         print('\x1bc', end='', flush=True)
 
     to_check = [] # type: T.List[str]
+    additional_to_check = [] # type: T.List[str]
     if opts.files:
         for f in opts.files:
             if f in modules:
                 to_check.append(f)
             elif any(f.startswith(i) for i in modules):
                 to_check.append(f)
+            elif f in additional:
+                additional_to_check.append(f)
+            elif any(f.startswith(i) for i in additional):
+                additional_to_check.append(f)
             else:
                 if not opts.quiet:
                     print(f'skipping {f!r} because it is not yet typed')
     else:
         to_check.extend(modules)
+        additional_to_check.extend(additional)
 
     if to_check:
         command = [opts.mypy] if opts.mypy else [sys.executable, '-m', 'mypy']
         if not opts.quiet:
             print('Running mypy (this can take some time) ...')
-        retcode = subprocess.run(command + args + to_check, cwd=root).returncode
+        retcode = subprocess.run(command + args + to_check + additional_to_check, cwd=root).returncode
         if opts.allver and retcode == 0:
             for minor in range(7, sys.version_info[1]):
                 if not opts.quiet: