From d8d7893cf77edeecbd22c5551a068e0664ed79a2 Mon Sep 17 00:00:00 2001
From: Anthony Sottile <asottile@umich.edu>
Date: Tue, 16 Sep 2014 17:27:40 -0700
Subject: [PATCH] Add ability to pass filenames as arguments.

---
 pre_commit/commands/run.py |  7 +++++--
 pre_commit/main.py         | 12 ++++++++----
 tests/commands/run_test.py | 10 ++++++++++
 3 files changed, 23 insertions(+), 6 deletions(-)

diff --git a/pre_commit/commands/run.py b/pre_commit/commands/run.py
index 1f1ee853..7d930ef0 100644
--- a/pre_commit/commands/run.py
+++ b/pre_commit/commands/run.py
@@ -49,7 +49,9 @@ def _print_user_skipped(hook, write, args):
 
 
 def _run_single_hook(runner, repository, hook, args, write, skips=set()):
-    if args.all_files:
+    if args.files:
+        get_filenames = git.get_files_matching(lambda: args.files)
+    elif args.all_files:
         get_filenames = git.get_all_files_matching
     elif git.is_in_merge_conflict():
         get_filenames = git.get_conflicted_files_matching
@@ -136,7 +138,8 @@ def run(runner, args, write=sys_stdout_write_wrapper, environ=os.environ):
         logger.error('Unmerged files.  Resolve before committing.')
         return 1
 
-    if args.no_stash or args.all_files:
+    # Don't stash if specified or files are specified
+    if args.no_stash or args.all_files or args.files:
         ctx = noop_context()
     else:
         ctx = staged_files_only(runner.cmd_runner)
diff --git a/pre_commit/main.py b/pre_commit/main.py
index fb1642bb..a8134b2d 100644
--- a/pre_commit/main.py
+++ b/pre_commit/main.py
@@ -55,10 +55,6 @@ def main(argv=None):
 
     run_parser = subparsers.add_parser('run', help='Run hooks.')
     run_parser.add_argument('hook', nargs='?', help='A single hook-id to run')
-    run_parser.add_argument(
-        '--all-files', '-a', action='store_true', default=False,
-        help='Run on all the files in the repo.  Implies --no-stash.',
-    )
     run_parser.add_argument(
         '--color', default='auto', type=color.use_color,
         help='Whether to use color in output.  Defaults to `auto`',
@@ -70,6 +66,14 @@ def main(argv=None):
     run_parser.add_argument(
         '--verbose', '-v', action='store_true', default=False,
     )
+    run_mutex_group = run_parser.add_mutually_exclusive_group(required=False)
+    run_mutex_group.add_argument(
+        '--all-files', '-a', action='store_true', default=False,
+        help='Run on all the files in the repo.  Implies --no-stash.',
+    )
+    run_mutex_group.add_argument(
+        '--files', nargs='*', help='Specific filenames to run hooks on.',
+    )
 
     help = subparsers.add_parser(
         'help', help='Show help for a specific command.'
diff --git a/tests/commands/run_test.py b/tests/commands/run_test.py
index 2f22c166..3a83a60c 100644
--- a/tests/commands/run_test.py
+++ b/tests/commands/run_test.py
@@ -43,13 +43,17 @@ def get_write_mock_output(write_mock):
 
 def _get_opts(
         all_files=False,
+        files=(),
         color=False,
         verbose=False,
         hook=None,
         no_stash=False,
 ):
+    # These are mutually exclusive
+    assert not (all_files and files)
     return auto_namedtuple(
         all_files=all_files,
+        files=files,
         color=color,
         verbose=verbose,
         hook=hook,
@@ -100,6 +104,12 @@ def test_run_all_hooks_failing(
             0,
             True,
         ),
+        (
+            {'files': ('foo.py',), 'verbose': True},
+            ('foo.py'),
+            0,
+            True,
+        ),
         ({}, ('Bash hook', '(no files to check)', 'Skipped'), 0, False),
     )
 )