Autoupdate works. Closes #44.

pre_commit/commands.py

@@ -6,8 +6,12 @@ import pkg_resources
 import stat
 from plumbum import local
 
+import pre_commit.constants as C
+from pre_commit.clientlib.validate_config import load_config
 from pre_commit.ordereddict import OrderedDict
 from pre_commit.repository import Repository
+from pre_commit.yaml_extensions import ordered_dump
+from pre_commit.yaml_extensions import ordered_load
 
 
 def install(runner):
@@ -75,4 +79,41 @@ def _update_repository(repo_config):
 
 def autoupdate(runner):
     """Auto-update the pre-commit config to the latest versions of repos."""
-    pass
+    retv = 0
+    output_configs = []
+    changed = False
+
+    input_configs = load_config(
+        runner.config_file_path,
+        load_strategy=ordered_load,
+    )
+
+    for repo_config in input_configs:
+        print('Updating {0}...'.format(repo_config['repo']), end='')
+        try:
+            new_repo_config = _update_repository(repo_config)
+        except RepositoryCannotBeUpdatedError as e:
+            print(e.args[0])
+            output_configs.append(repo_config)
+            retv = 1
+            continue
+
+        if new_repo_config['sha'] != repo_config['sha']:
+            changed = True
+            print(
+                'updating {0} -> {1}.'.format(
+                    repo_config['sha'], new_repo_config['sha'],
+                )
+            )
+            output_configs.append(new_repo_config)
+        else:
+            print('already up to date.')
+            output_configs.append(repo_config)
+
+    if changed:
+        with open(runner.config_file_path, 'w') as config_file:
+            config_file.write(
+                ordered_dump(output_configs, **C.YAML_DUMP_KWARGS)
+            )
+
+    return retv

pre_commit/constants.py

@@ -10,3 +10,9 @@ SUPPORTED_LANGUAGES = set([
     'ruby',
     'node',
 ])
+
+
+YAML_DUMP_KWARGS = {
+    'default_flow_style': False,
+    'indent': 4,
+}

pre_commit/yaml_extensions.py

@@ -18,7 +18,7 @@ def ordered_load(s):
 
 
 def ordered_dump(s, **kwargs):
-    class OrderedDumper(yaml.dumper.Dumper): pass
+    class OrderedDumper(yaml.dumper.SafeDumper): pass
     def dict_representer(dumper, data):
         return dumper.represent_mapping(
             yaml.resolver.BaseResolver.DEFAULT_MAPPING_TAG,

tests/commands_test.py

@@ -8,15 +8,18 @@ import shutil
 import stat
 from plumbum import local
 
+import pre_commit.constants as C
 from pre_commit import git
 from pre_commit.clientlib.validate_config import CONFIG_JSON_SCHEMA
 from pre_commit.clientlib.validate_config import validate_config_extra
+from pre_commit.commands import autoupdate
 from pre_commit.commands import install
 from pre_commit.commands import RepositoryCannotBeUpdatedError
 from pre_commit.commands import uninstall
 from pre_commit.commands import _update_repository
 from pre_commit.ordereddict import OrderedDict
 from pre_commit.runner import Runner
+from pre_commit.yaml_extensions import ordered_dump
 from testing.auto_namedtuple import auto_namedtuple
 from testing.util import get_resource_path
 
@@ -54,10 +57,16 @@ def up_to_date_repo(python_hooks_repo):
     config = OrderedDict((
         ('repo', python_hooks_repo),
         ('sha', git.get_head_sha(python_hooks_repo)),
-        ('hooks', [{'id': 'foo', 'files': ''}]),
+        ('hooks', [OrderedDict((('id', 'foo'), ('files', '')))]),
     ))
     jsonschema.validate([config], CONFIG_JSON_SCHEMA)
     validate_config_extra([config])
+
+    with open(os.path.join(python_hooks_repo, C.CONFIG_FILE), 'w') as file_obj:
+        file_obj.write(
+            ordered_dump([config], **C.YAML_DUMP_KWARGS)
+        )
+
     yield auto_namedtuple(
         repo_config=config,
         python_hooks_repo=python_hooks_repo,
@@ -70,17 +79,32 @@ def test_up_to_date_repo(up_to_date_repo):
     assert ret['sha'] == input_sha
 
 
+def test_autoupdate_up_to_date_repo(up_to_date_repo):
+    before = open(C.CONFIG_FILE).read()
+    runner = Runner(up_to_date_repo.python_hooks_repo)
+    ret = autoupdate(runner)
+    after = open(C.CONFIG_FILE).read()
+    assert ret == 0
+    assert before == after
+
+
 @pytest.yield_fixture
 def out_of_date_repo(python_hooks_repo):
     config = OrderedDict((
         ('repo', python_hooks_repo),
         ('sha', git.get_head_sha(python_hooks_repo)),
-        ('hooks', [{'id': 'foo', 'files': ''}]),
+        ('hooks', [OrderedDict((('id', 'foo'), ('files', '')))]),
     ))
     jsonschema.validate([config], CONFIG_JSON_SCHEMA)
     validate_config_extra([config])
     local['git']['commit', '--allow-empty', '-m', 'foo']()
     head_sha = git.get_head_sha(python_hooks_repo)
+
+    with open(os.path.join(python_hooks_repo, C.CONFIG_FILE), 'w') as file_obj:
+        file_obj.write(
+            ordered_dump([config], **C.YAML_DUMP_KWARGS)
+        )
+
     yield auto_namedtuple(
         repo_config=config,
         head_sha=head_sha,
@@ -93,18 +117,34 @@ def test_out_of_date_repo(out_of_date_repo):
     assert ret['sha'] == out_of_date_repo.head_sha
 
 
+def test_autoupdate_out_of_date_repo(out_of_date_repo):
+    before = open(C.CONFIG_FILE).read()
+    runner = Runner(out_of_date_repo.python_hooks_repo)
+    ret = autoupdate(runner)
+    after = open(C.CONFIG_FILE).read()
+    assert ret == 0
+    assert before != after
+    assert out_of_date_repo.head_sha in after
+
+
 @pytest.yield_fixture
 def hook_disappearing_repo(python_hooks_repo):
     config = OrderedDict((
         ('repo', python_hooks_repo),
         ('sha', git.get_head_sha(python_hooks_repo)),
-        ('hooks', [{'id': 'foo', 'files': ''}]),
+        ('hooks', [OrderedDict((('id', 'foo'), ('files', '')))]),
     ))
     jsonschema.validate([config], CONFIG_JSON_SCHEMA)
     validate_config_extra([config])
-    shutil.copy(get_resource_path('manifest_without_foo.yaml'), 'manifest.yaml')
+    shutil.copy(get_resource_path('manifest_without_foo.yaml'), C.MANIFEST_FILE)
     local['git']['add', '.']()
     local['git']['commit', '-m', 'Remove foo']()
+
+    with open(os.path.join(python_hooks_repo, C.CONFIG_FILE), 'w') as file_obj:
+        file_obj.write(
+            ordered_dump([config], **C.YAML_DUMP_KWARGS)
+        )
+
     yield auto_namedtuple(
         repo_config=config,
         python_hooks_repo=python_hooks_repo,
@@ -114,3 +154,12 @@ def hook_disappearing_repo(python_hooks_repo):
 def test_hook_disppearing_repo_raises(hook_disappearing_repo):
     with pytest.raises(RepositoryCannotBeUpdatedError):
         _update_repository(hook_disappearing_repo.repo_config)
+
+
+def test_autoupdate_hook_disappearing_repo(hook_disappearing_repo):
+    before = open(C.CONFIG_FILE).read()
+    runner = Runner(hook_disappearing_repo.python_hooks_repo)
+    ret = autoupdate(runner)
+    after = open(C.CONFIG_FILE).read()
+    assert ret == 1
+    assert before == after

tests/yaml_extensions_test.py

@@ -1,4 +1,5 @@
 
+import pre_commit.constants as C
 from pre_commit.ordereddict import OrderedDict
 from pre_commit.yaml_extensions import ordered_dump
 from pre_commit.yaml_extensions import ordered_load
@@ -25,7 +26,7 @@ def test_ordered_dump():
         OrderedDict(
             (('a', 'herp'), ('c', 'derp'), ('b', 'harp'), ('d', 'darp'))
         ),
-        default_flow_style=False,
+        **C.YAML_DUMP_KWARGS
     )
     assert ret == (
         'a: herp\n'