Add pre-commit try-repo

`try-repo` is useful for:
- Trying out a remote hook repository without needing to configure it.
- Testing a hook repository while developing it.

pre_commit/commands/try_repo.py

@@ -0,0 +1,44 @@
+from __future__ import absolute_import
+from __future__ import unicode_literals
+
+import collections
+import os.path
+
+from aspy.yaml import ordered_dump
+
+import pre_commit.constants as C
+from pre_commit import git
+from pre_commit import output
+from pre_commit.commands.run import run
+from pre_commit.manifest import Manifest
+from pre_commit.runner import Runner
+from pre_commit.store import Store
+from pre_commit.util import tmpdir
+
+
+def try_repo(args):
+    ref = args.ref or git.head_sha(args.repo)
+
+    with tmpdir() as tempdir:
+        if args.hook:
+            hooks = [{'id': args.hook}]
+        else:
+            manifest = Manifest(Store(tempdir).clone(args.repo, ref))
+            hooks = [{'id': hook_id} for hook_id in sorted(manifest.hooks)]
+
+        items = (('repo', args.repo), ('sha', ref), ('hooks', hooks))
+        config = {'repos': [collections.OrderedDict(items)]}
+        config_s = ordered_dump(config, **C.YAML_DUMP_KWARGS)
+
+        config_filename = os.path.join(tempdir, C.CONFIG_FILE)
+        with open(config_filename, 'w') as cfg:
+            cfg.write(config_s)
+
+        output.write_line('=' * 79)
+        output.write_line('Using config:')
+        output.write_line('=' * 79)
+        output.write(config_s)
+        output.write_line('=' * 79)
+
+        runner = Runner('.', config_filename, store_dir=tempdir)
+        return run(runner, args)

pre_commit/git.py

@@ -97,6 +97,11 @@ def get_changed_files(new, old):
     )[1])
 
 
+def head_sha(remote):
+    _, out, _ = cmd_output('git', 'ls-remote', '--exit-code', remote, 'HEAD')
+    return out.split()[0]
+
+
 def check_for_cygwin_mismatch():
     """See https://github.com/pre-commit/pre-commit/issues/354"""
     if sys.platform in ('cygwin', 'win32'):  # pragma: no cover (windows)

pre_commit/main.py

@@ -17,6 +17,7 @@ from pre_commit.commands.install_uninstall import uninstall
 from pre_commit.commands.migrate_config import migrate_config
 from pre_commit.commands.run import run
 from pre_commit.commands.sample_config import sample_config
+from pre_commit.commands.try_repo import try_repo
 from pre_commit.error_handler import error_handler
 from pre_commit.logging_handler import add_logging_handler
 from pre_commit.runner import Runner
@@ -53,6 +54,41 @@ def _add_hook_type_option(parser):
     )
 
 
+def _add_run_options(parser):
+    parser.add_argument('hook', nargs='?', help='A single hook-id to run')
+    parser.add_argument('--verbose', '-v', action='store_true', default=False)
+    parser.add_argument(
+        '--origin', '-o',
+        help="The origin branch's commit_id when using `git push`.",
+    )
+    parser.add_argument(
+        '--source', '-s',
+        help="The remote branch's commit_id when using `git push`.",
+    )
+    parser.add_argument(
+        '--commit-msg-filename',
+        help='Filename to check when running during `commit-msg`',
+    )
+    parser.add_argument(
+        '--hook-stage', choices=('commit', 'push', 'commit-msg'),
+        default='commit',
+        help='The stage during which the hook is fired e.g. commit or push.',
+    )
+    parser.add_argument(
+        '--show-diff-on-failure', action='store_true',
+        help='When hooks fail, run `git diff` directly afterward.',
+    )
+    mutex_group = parser.add_mutually_exclusive_group(required=False)
+    mutex_group.add_argument(
+        '--all-files', '-a', action='store_true', default=False,
+        help='Run on all the files in the repo.',
+    )
+    mutex_group.add_argument(
+        '--files', nargs='*', default=[],
+        help='Specific filenames to run hooks on.',
+    )
+
+
 def main(argv=None):
     argv = argv if argv is not None else sys.argv[1:]
     argv = [five.to_text(arg) for arg in argv]
@@ -142,40 +178,7 @@ def main(argv=None):
     run_parser = subparsers.add_parser('run', help='Run hooks.')
     _add_color_option(run_parser)
     _add_config_option(run_parser)
-    run_parser.add_argument('hook', nargs='?', help='A single hook-id to run')
-    run_parser.add_argument(
-        '--verbose', '-v', action='store_true', default=False,
-    )
-    run_parser.add_argument(
-        '--origin', '-o',
-        help="The origin branch's commit_id when using `git push`.",
-    )
-    run_parser.add_argument(
-        '--source', '-s',
-        help="The remote branch's commit_id when using `git push`.",
-    )
-    run_parser.add_argument(
-        '--commit-msg-filename',
-        help='Filename to check when running during `commit-msg`',
-    )
-    run_parser.add_argument(
-        '--hook-stage', choices=('commit', 'push', 'commit-msg'),
-        default='commit',
-        help='The stage during which the hook is fired e.g. commit or push.',
-    )
-    run_parser.add_argument(
-        '--show-diff-on-failure', action='store_true',
-        help='When hooks fail, run `git diff` directly afterward.',
-    )
-    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.',
-    )
-    run_mutex_group.add_argument(
-        '--files', nargs='*', default=[],
-        help='Specific filenames to run hooks on.',
-    )
+    _add_run_options(run_parser)
 
     sample_config_parser = subparsers.add_parser(
         'sample-config', help='Produce a sample {} file'.format(C.CONFIG_FILE),
@@ -183,6 +186,24 @@ def main(argv=None):
     _add_color_option(sample_config_parser)
     _add_config_option(sample_config_parser)
 
+    try_repo_parser = subparsers.add_parser(
+        'try-repo',
+        help='Try the hooks in a repository, useful for developing new hooks.',
+    )
+    _add_color_option(try_repo_parser)
+    _add_config_option(try_repo_parser)
+    try_repo_parser.add_argument(
+        'repo', help='Repository to source hooks from.',
+    )
+    try_repo_parser.add_argument(
+        '--ref',
+        help=(
+            'Manually select a ref to run against, otherwise the `HEAD` '
+            'revision will be used.'
+        ),
+    )
+    _add_run_options(try_repo_parser)
+
     help = subparsers.add_parser(
         'help', help='Show help for a specific command.',
     )
@@ -231,6 +252,8 @@ def main(argv=None):
             return run(runner, args)
         elif args.command == 'sample-config':
             return sample_config()
+        elif args.command == 'try-repo':
+            return try_repo(args)
         else:
             raise NotImplementedError(
                 'Command {} not implemented.'.format(args.command),

pre_commit/manifest.py

@@ -14,9 +14,8 @@ logger = logging.getLogger('pre_commit')
 
 
 class Manifest(object):
-    def __init__(self, repo_path, repo_url):
+    def __init__(self, repo_path):
         self.repo_path = repo_path
-        self.repo_url = repo_url
 
     @cached_property
     def manifest_contents(self):

pre_commit/repository.py

@@ -146,7 +146,7 @@ class Repository(object):
 
     @cached_property
     def manifest(self):
-        return Manifest(self._repo_path, self.repo_config['repo'])
+        return Manifest(self._repo_path)
 
     @cached_property
     def hooks(self):

pre_commit/runner.py

@@ -15,13 +15,14 @@ class Runner(object):
     repository under test.
     """
 
-    def __init__(self, git_root, config_file):
+    def __init__(self, git_root, config_file, store_dir=None):
         self.git_root = git_root
         self.config_file = config_file
+        self._store_dir = store_dir
 
     @classmethod
     def create(cls, config_file):
-        """Creates a PreCommitRunner by doing the following:
+        """Creates a Runner by doing the following:
             - Finds the root of the current git repository
             - chdir to that directory
         """
@@ -63,4 +64,4 @@ class Runner(object):
 
     @cached_property
     def store(self):
-        return Store()
+        return Store(self._store_dir)