Target files by type as well as path regex

pre_commit/commands/run.py

@@ -55,24 +55,37 @@ def get_changed_files(new, old):
     )[1].splitlines()
 
 
-def get_filenames(args, include_expr, exclude_expr):
+def get_filenames(args, include_expr, exclude_expr, types):
+    """Return a list of file names and modes to consider for this run.
+
+    :return: a list of tuples of the of the form (path, mode).
+    """
     if args.origin and args.source:
         getter = git.get_files_matching(
             lambda: get_changed_files(args.origin, args.source),
         )
     elif args.files:
-        getter = git.get_files_matching(lambda: args.files)
+        files = [
+            (path, git.guess_git_type_for_file(path))
+            for path in args.files
+        ]
+        getter = git.get_files_matching(lambda: files)
     elif args.all_files:
         getter = git.get_all_files_matching
     elif git.is_in_merge_conflict():
         getter = git.get_conflicted_files_matching
     else:
         getter = git.get_staged_files_matching
-    return getter(include_expr, exclude_expr)
+    return getter(include_expr, exclude_expr, types)
 
 
 def _run_single_hook(hook, repo, args, write, skips=frozenset()):
-    filenames = get_filenames(args, hook['files'], hook['exclude'])
+    filenames = get_filenames(
+        args,
+        hook['files'],
+        hook['exclude'],
+        frozenset(hook['types']) if 'types' in hook else frozenset(['file']),
+    )
     if hook['id'] in skips:
         _print_user_skipped(hook, write, args)
         return 0

pre_commit/git.py

@@ -56,6 +56,7 @@ def parse_merge_msg_for_conflicts(merge_msg):
 
 @memoize_by_cwd
 def get_conflicted_files():
+    """Return a list of file names and types for conflicted files."""
     logger.info('Checking merge-conflict files only.')
     # Need to get the conflicted files from the MERGE_MSG because they could
     # have resolved the conflict by choosing one side or the other
@@ -69,32 +70,105 @@ def get_conflicted_files():
     merge_diff_filenames = cmd_output(
         'git', 'diff', '-m', tree_hash, 'HEAD', 'MERGE_HEAD', '--name-only',
     )[1].splitlines()
-    return set(merge_conflict_filenames) | set(merge_diff_filenames)
+
+    return [
+        (path, get_git_type_for_file(path))
+        for path
+        in set(merge_conflict_filenames) | set(merge_diff_filenames)
+    ]
+
+
+def get_git_type_for_file(path):
+    """Return the git type of a file which is in this git repository.
+
+    Because the file is in this git repository, we can use `git ls-files` to
+    read its type directly.
+    """
+    # TODO: call this function once with a list of paths for more speed?
+    _, mode = _parse_git_ls_line(
+        cmd_output('git', 'ls-files', '--stage', '--', path)[1],
+    )
+    return mode
+
+
+def guess_git_type_for_file(path):
+    """Return a guessed git type of a file which is not in this git repository.
+
+    Because the file isn't in git, we must guess the file type. This is
+    necessary when using `pre-commit run` or `pre-commit identify` and listing
+    files (which might not be in a repo).
+    """
+    if os.path.islink(path):
+        return GIT_MODE_SYMLINK
+    elif os.path.isfile(path):
+        # determine if executable
+        if os.stat(path).st_mode & 0o111:
+            return GIT_MODE_EXECUTABLE
+        else:
+            return GIT_MODE_FILE
+    elif os.path.isdir(path):
+        # git doesn't track directories, so if it *is* one, it's a submodule
+        return GIT_MODE_SUBMODULE
+    else:
+        raise ValueError('Unable to determine type of `{0}`'.format(path))
 
 
 @memoize_by_cwd
 def get_staged_files():
-    return cmd_output('git', 'diff', '--staged', '--name-only')[1].splitlines()
+    """Return a list of paths in the repo which have been added/modified."""
+    return [
+        (path, get_git_type_for_file(path))
+        for path
+        in cmd_output(
+            'git', 'diff',
+            '--diff-filter=ACMRTUXB',  # all types except D ("Deleted")
+            '--staged',
+            '--name-only',
+        )[1].splitlines()
+    ]
+
+
+# The output format of the command is:
+# [file mode] [object hash] [stage number]\t[file path]
+# (We only care about the mode and path.)
+_split_git_ls_line_regex = re.compile('^([0-7]{6}) [0-9a-f]{40} [0-9]+\t(.+)$')
+
+
+def _parse_git_ls_line(line):
+    """Split a line of `git ls-files` into a tuple (path, type)."""
+    match = _split_git_ls_line_regex.match(line)
+    return match.group(2), int(match.group(1), 8)
 
 
 @memoize_by_cwd
 def get_all_files():
-    return cmd_output('git', 'ls-files')[1].splitlines()
+    """Return a list of all files (and their types) in the repository.
+
+    :return: list of (path, type) tuples
+    """
+    return [
+        _parse_git_ls_line(line)
+        for line in cmd_output('git', 'ls-files', '--stage')[1].splitlines()
+    ]
 
 
 def get_files_matching(all_file_list_strategy):
     @functools.wraps(all_file_list_strategy)
     @memoize_by_cwd
-    def wrapper(include_expr, exclude_expr):
+    def wrapper(include_expr, exclude_expr, types):
+        # TODO: how to avoid this?
+        from pre_commit.file_classifier.classifier import classify
+
         include_regex = re.compile(include_expr)
         exclude_regex = re.compile(exclude_expr)
         return set(
             filename
-            for filename in all_file_list_strategy()
+            for filename, mode in all_file_list_strategy()
             if (
                 include_regex.search(filename) and
                 not exclude_regex.search(filename) and
-                os.path.lexists(filename)
+                os.path.lexists(filename) and
+                classify(filename, mode).intersection(types)
             )
         )
     return wrapper

tests/git_test.py

@@ -58,18 +58,18 @@ def test_cherry_pick_conflict(in_merge_conflict):
 def get_files_matching_func():
     def get_filenames():
         return (
-            'pre_commit/main.py',
-            'pre_commit/git.py',
-            'im_a_file_that_doesnt_exist.py',
-            'testing/test_symlink',
-            'hooks.yaml',
+            ('pre_commit/main.py', git.GIT_MODE_FILE),
+            ('pre_commit/git.py', git.GIT_MODE_FILE),
+            ('im_a_file_that_doesnt_exist.py', git.GIT_MODE_FILE),
+            ('testing/test_symlink', git.GIT_MODE_SYMLINK),
+            ('hooks.yaml', git.GIT_MODE_FILE),
         )
 
     return git.get_files_matching(get_filenames)
 
 
 def test_get_files_matching_base(get_files_matching_func):
-    ret = get_files_matching_func('', '^$')
+    ret = get_files_matching_func('', '^$', frozenset(['file', 'symlink']))
     assert ret == set([
         'pre_commit/main.py',
         'pre_commit/git.py',
@@ -79,7 +79,7 @@ def test_get_files_matching_base(get_files_matching_func):
 
 
 def test_get_files_matching_total_match(get_files_matching_func):
-    ret = get_files_matching_func('^.*\\.py$', '^$')
+    ret = get_files_matching_func('^.*\\.py$', '^$', frozenset(['file']))
     assert ret == set([
         'pre_commit/main.py',
         'pre_commit/git.py',
@@ -87,17 +87,17 @@ def test_get_files_matching_total_match(get_files_matching_func):
 
 
 def test_does_search_instead_of_match(get_files_matching_func):
-    ret = get_files_matching_func('\\.yaml$', '^$')
+    ret = get_files_matching_func('\\.yaml$', '^$', frozenset(['file']))
     assert ret == set(['hooks.yaml'])
 
 
-def test_does_not_include_deleted_fileS(get_files_matching_func):
-    ret = get_files_matching_func('exist.py', '^$')
+def test_does_not_include_deleted_files(get_files_matching_func):
+    ret = get_files_matching_func('exist.py', '^$', frozenset(['file']))
     assert ret == set()
 
 
 def test_exclude_removes_files(get_files_matching_func):
-    ret = get_files_matching_func('', '\\.py$')
+    ret = get_files_matching_func('', '\\.py$', frozenset(['file', 'symlink']))
     assert ret == set(['hooks.yaml', 'testing/test_symlink'])
 
 
@@ -114,12 +114,17 @@ def test_get_conflicted_files(in_merge_conflict):
     cmd_output('git', 'add', 'other_file')
 
     ret = set(git.get_conflicted_files())
-    assert ret == set(('conflict_file', 'other_file'))
+    assert ret == set([
+        ('conflict_file', git.GIT_MODE_FILE),
+        ('other_file', git.GIT_MODE_FILE),
+    ])
 
 
 def test_get_conflicted_files_in_submodule(in_conflicting_submodule):
     resolve_conflict()
-    assert set(git.get_conflicted_files()) == set(('conflict_file',))
+    assert set(git.get_conflicted_files()) == set([
+        ('conflict_file', git.GIT_MODE_FILE)],
+    )
 
 
 def test_get_conflicted_files_unstaged_files(in_merge_conflict):
@@ -132,7 +137,9 @@ def test_get_conflicted_files_unstaged_files(in_merge_conflict):
         bar_only_file.write('new contents!\n')
 
     ret = set(git.get_conflicted_files())
-    assert ret == set(('conflict_file',))
+    assert ret == set([
+        ('conflict_file', git.GIT_MODE_FILE),
+    ])
 
 
 MERGE_MSG = "Merge branch 'foo' into bar\n\nConflicts:\n\tconflict_file\n"