Remove py26 format literals

Resolves #403

pre_commit/clientlib/validate_base.py

@@ -38,7 +38,7 @@ def get_validator(
     """
     def validate(filename, load_strategy=yaml.load):
         if not os.path.exists(filename):
-            raise exception_type('File {0} does not exist'.format(filename))
+            raise exception_type('File {} does not exist'.format(filename))
 
         file_contents = open(filename, 'r').read()
 
@@ -46,14 +46,14 @@ def get_validator(
             obj = load_strategy(file_contents)
         except Exception as e:
             raise exception_type(
-                'Invalid yaml: {0}\n{1}'.format(os.path.relpath(filename), e),
+                'Invalid yaml: {}\n{}'.format(os.path.relpath(filename), e),
             )
 
         try:
             jsonschema.validate(obj, json_schema)
         except jsonschema.exceptions.ValidationError as e:
             raise exception_type(
-                'Invalid content: {0}\n{1}'.format(
+                'Invalid content: {}\n{}'.format(
                     os.path.relpath(filename), e
                 ),
             )
@@ -75,7 +75,7 @@ def get_run_function(filenames_help, validate_strategy, exception_cls):
         parser.add_argument(
             '-V', '--version',
             action='version',
-            version='%(prog)s {0}'.format(
+            version='%(prog)s {}'.format(
                 pkg_resources.get_distribution('pre-commit').version
             )
         )

pre_commit/clientlib/validate_config.py

@@ -57,7 +57,7 @@ CONFIG_JSON_SCHEMA = {
 def try_regex(repo, hook, value, field_name):
     if not is_regex_valid(value):
         raise InvalidConfigError(
-            'Invalid {0} regex at {1}, {2}: {3}'.format(
+            'Invalid {} regex at {}, {}: {}'.format(
                 field_name, repo, hook, value,
             )
         )
@@ -72,7 +72,7 @@ def validate_config_extra(config):
                 )
         elif 'sha' not in repo:
             raise InvalidConfigError(
-                'Missing "sha" field for repository {0}'.format(repo['repo'])
+                'Missing "sha" field for repository {}'.format(repo['repo'])
             )
         for hook in repo['hooks']:
             try_regex(repo, hook['id'], hook.get('files', ''), 'files')

pre_commit/clientlib/validate_manifest.py

@@ -55,7 +55,7 @@ MANIFEST_JSON_SCHEMA = {
 def validate_languages(hook_config):
     if hook_config['language'] not in all_languages:
         raise InvalidManifestError(
-            'Expected language {0} for {1} to be one of {2!r}'.format(
+            'Expected language {} for {} to be one of {!r}'.format(
                 hook_config['id'],
                 hook_config['language'],
                 all_languages,
@@ -66,14 +66,14 @@ def validate_languages(hook_config):
 def validate_files(hook_config):
     if not is_regex_valid(hook_config['files']):
         raise InvalidManifestError(
-            'Invalid files regex at {0}: {1}'.format(
+            'Invalid files regex at {}: {}'.format(
                 hook_config['id'], hook_config['files'],
             )
         )
 
     if not is_regex_valid(hook_config.get('exclude', '')):
         raise InvalidManifestError(
-            'Invalid exclude regex at {0}: {1}'.format(
+            'Invalid exclude regex at {}: {}'.format(
                 hook_config['id'], hook_config['exclude'],
             )
         )