Merge pull request #837 from georgeyk/check-useless-excludes-type-filter

Fix `check-useless-exclude` to consider types filter

pre_commit/meta_hooks/check_useless_excludes.py

@@ -9,6 +9,7 @@ import pre_commit.constants as C
 from pre_commit import git
 from pre_commit.clientlib import load_config
 from pre_commit.clientlib import MANIFEST_HOOK_DICT
+from pre_commit.commands.run import _filter_by_types
 
 
 def exclude_matches_any(filenames, include, exclude):
@@ -39,8 +40,10 @@ def check_useless_excludes(config_file):
             # Not actually a manifest dict, but this more accurately reflects
             # the defaults applied during runtime
             hook = apply_defaults(hook, MANIFEST_HOOK_DICT)
+            types, exclude_types = hook['types'], hook['exclude_types']
+            filtered_by_types = _filter_by_types(files, types, exclude_types)
             include, exclude = hook['files'], hook['exclude']
-            if not exclude_matches_any(files, include, exclude):
+            if not exclude_matches_any(filtered_by_types, include, exclude):
                 print(
                     'The exclude pattern {!r} for {} does not match any files'
                     .format(exclude, hook['id']),

tests/meta_hooks/check_useless_excludes_test.py

@@ -51,6 +51,37 @@ def test_useless_exclude_for_hook(capsys, tempdir_factory):
     assert expected == out
 
 
+def test_useless_exclude_with_types_filter(capsys, tempdir_factory):
+    config = {
+        'repos': [
+            {
+                'repo': 'meta',
+                'hooks': [
+                    {
+                        'id': 'check-useless-excludes',
+                        'exclude': '.pre-commit-config.yaml',
+                        'types': ['python'],
+                    },
+                ],
+            },
+        ],
+    }
+
+    repo = git_dir(tempdir_factory)
+    add_config_to_repo(repo, config)
+
+    with cwd(repo):
+        assert check_useless_excludes.main(()) == 1
+
+    out, _ = capsys.readouterr()
+    out = out.strip()
+    expected = (
+        "The exclude pattern '.pre-commit-config.yaml' for "
+        "check-useless-excludes does not match any files"
+    )
+    assert expected == out
+
+
 def test_no_excludes(capsys, tempdir_factory):
     config = {
         'repos': [