Pretty yaml

pre_commit_hooks/pretty_format_yaml.py

@@ -0,0 +1,127 @@
+from __future__ import print_function
+
+import argparse
+import sys
+
+import yaml
+
+
+def _get_pretty_format(content, **kwargs):
+    return yaml.safe_dump(yaml.safe_load(content), **kwargs)
+
+
+def _autofix(filename, new_contents):
+    print("Fixing file {0}".format(filename))
+    with open(filename, 'w') as f:
+        f.write(new_contents)
+
+
+def filter_argument(accepted_values):
+    def _validate(s):
+        try:
+            return {str(v): v for v in accepted_values}[s]
+        except:
+            raise argparse.ArgumentTypeError('Accepted values are: {}'.format(accepted_values))
+    return _validate
+
+
+def none_or_boolean_argument(s):
+    return filter_argument([None, True, False])(s)
+
+
+def pretty_format_yaml(argv=None):
+    parser = argparse.ArgumentParser()
+
+    parser.add_argument(
+        '--autofix',
+        action='store_true',
+        dest='autofix',
+        help='Automatically fixes encountered not-pretty-formatted files',
+    )
+
+    parser.add_argument(
+        '--default_style',
+        help='PyYAML dump parameter. More info on http://pyyaml.org/wiki/PyYAMLDocumentation#Dumper'
+    )
+    parser.add_argument(
+        '--default_flow_style', type=none_or_boolean_argument,
+        help='PyYAML dump parameter. More info on http://pyyaml.org/wiki/PyYAMLDocumentation#Dumper'
+    )
+    parser.add_argument(
+        '--canonical', type=none_or_boolean_argument,
+        help='PyYAML dump parameter. More info on http://pyyaml.org/wiki/PyYAMLDocumentation#Dumper'
+    )
+    parser.add_argument(
+        '--indent', type=int,
+        help='PyYAML dump parameter. More info on http://pyyaml.org/wiki/PyYAMLDocumentation#Dumper'
+    )
+    parser.add_argument(
+        '--width', type=int,
+        help='PyYAML dump parameter. More info on http://pyyaml.org/wiki/PyYAMLDocumentation#Dumper'
+    )
+    parser.add_argument(
+        '--allow_unicode', type=none_or_boolean_argument,
+        help='PyYAML dump parameter. More info on http://pyyaml.org/wiki/PyYAMLDocumentation#Dumper'
+    )
+    parser.add_argument(
+        '--line_break', type=none_or_boolean_argument,
+        help='PyYAML dump parameter. More info on http://pyyaml.org/wiki/PyYAMLDocumentation#Dumper'
+    )
+    parser.add_argument(
+        '--encoding',
+        help='PyYAML dump parameter. More info on http://pyyaml.org/wiki/PyYAMLDocumentation#Dumper'
+    )
+    parser.add_argument(
+        '--explicit_start', type=none_or_boolean_argument,
+        help='PyYAML dump parameter. More info on http://pyyaml.org/wiki/PyYAMLDocumentation#Dumper'
+    )
+    parser.add_argument(
+        '--explicit_end', type=none_or_boolean_argument,
+        help='PyYAML dump parameter. More info on http://pyyaml.org/wiki/PyYAMLDocumentation#Dumper'
+    )
+    parser.add_argument(
+        '--version',
+        help='PyYAML dump parameter. More info on http://pyyaml.org/wiki/PyYAMLDocumentation#Dumper'
+    )
+    parser.add_argument(
+        '--tags',
+        help='PyYAML dump parameter. More info on http://pyyaml.org/wiki/PyYAMLDocumentation#Dumper'
+    )
+    parser.add_argument('filenames', nargs='*', help='Filenames to fix')
+    args = parser.parse_args(argv)
+
+    pyyaml_kwargs = {
+        key: value
+        for key, value in args._get_kwargs()
+        if key != 'autofix' and key != 'filenames'
+    }
+
+    status = 0
+
+    for yaml_file in args.filenames:
+        with open(yaml_file) as f:
+            contents = f.read()
+
+        try:
+            pretty_contents = _get_pretty_format(contents, **pyyaml_kwargs)
+
+            if contents != pretty_contents:
+                print("File {0} is not pretty-formatted".format(yaml_file))
+
+                if args.autofix:
+                    _autofix(yaml_file, pretty_contents)
+
+                status = 1
+
+        except yaml.YAMLError:
+            print(
+                "Input File {0} is not a valid YAML, consider using check-yaml"
+                .format(yaml_file)
+            )
+            return 1
+
+    return status
+
+
+if __name__ == '__main__':
+    sys.exit(pretty_format_yaml(sys.argv[1:]))