Upgrade Python syntax with pyupgrade

https://github.com/asottile/pyupgrade

tests/rules/test_indentation.py

@@ -51,7 +51,7 @@ class IndentationStackTestCase(RuleTestCase):
                           .replace('Mapping', 'Map'))
             if token_type in ('StreamStart', 'StreamEnd'):
                 continue
-            output += '%9s %s\n' % (token_type,
+            output += '{:>9} {}\n'.format(token_type,
                                           self.format_stack(context['stack']))
         return output
 

yamllint/cli.py

@@ -103,7 +103,7 @@ def run(argv=None):
                         help='return non-zero exit code on warnings '
                              'as well as errors')
     parser.add_argument('-v', '--version', action='version',
-                        version='%s %s' % (APP_NAME, APP_VERSION))
+                        version='{} {}'.format(APP_NAME, APP_VERSION))
 
     # TODO: read from stdin when no filename?
 

yamllint/linter.py

@@ -47,7 +47,7 @@ class LintProblem(object):
     @property
     def message(self):
         if self.rule is not None:
-            return '%s (%s)' % (self.desc, self.rule)
+            return '{} ({})'.format(self.desc, self.rule)
         return self.desc
 
     def __eq__(self, other):
@@ -78,7 +78,7 @@ def get_cosmetic_problems(buffer, conf, filepath):
     class DisableDirective:
         def __init__(self):
             self.rules = set()
-            self.all_rules = set([r.ID for r in rules])
+            self.all_rules = {r.ID for r in rules}
 
         def process_comment(self, comment):
             try: