From b485697742734a8543e29b9f49872ded9209e5eb Mon Sep 17 00:00:00 2001
From: Tino de Bruijn <work@tino.io>
Date: Fri, 28 Jul 2017 11:35:20 +0200
Subject: [PATCH] Implement --only and --exclude flags

---
 git_lint/git_lint.py | 28 +++++++++++++++++++---------
 1 file changed, 19 insertions(+), 9 deletions(-)

diff --git a/git_lint/git_lint.py b/git_lint/git_lint.py
index 884c81d..296ab5c 100644
--- a/git_lint/git_lint.py
+++ b/git_lint/git_lint.py
@@ -19,7 +19,7 @@ try:  # noqa: F401
     from typing import Dict, List, Text, Any, Optional, Union, Callable, Tuple  # noqa: F401
 except:  # noqa: F401
     pass  # noqa: F401
-    
+
 
 _ = gettext.gettext
 
@@ -46,36 +46,36 @@ def load_config(options, base):
 
     def find_config_file(options, base):
         """ Returns the configuration file from a prioritized list of locations.
-    
+
         Locations are prioritized as:
             1. From the command line. Fail if specified but not found
             2. The repository's root directory, as the file .git-lint
             3. The repository's root directory, as the file .git-lint/config
             4. The user's home directory, as file .git-lint
             5. The user's home directory, as the file .git-lint/config
-    
+
         If no configuration file is found, this is an error.
         """
-    
+
         if 'config' in options:
             config = options['config']
             configpath = os.path.abspath(config)
             if not os.path.isfile(configpath):
                 sys.exit(_('Configuration file not found: {}\n').format(config))
             return configpath
-    
+
         home = os.environ.get('HOME', None)
         possibles = [os.path.join(base, '.git-lint'),
                      os.path.join(base, '.git-lint/config')] + ((home and [
                          os.path.join(home, '.git-lint'),
                          os.path.join(home, '.git-lint/config')]) or [])
-    
+
         matches = [p for p in possibles if os.path.isfile(p)]
         if len(matches) == 0:
             sys.exit(_('No configuration file found, tried: {}').format(':'.join(possibles)))
-    
+
         return matches[0]
-    
+
     Linter = namedtuple('Linter', ['name', 'linter'])
     path = find_config_file(options, base)
     configloader = configparser.SafeConfigParser()
@@ -201,7 +201,7 @@ def get_linter_status(config):
     def get_working_linter_names(config):
         return [i.name for i in config
                 if linter_exists(i.linter['command'], i.name)]
-    
+
     working_linter_names = get_working_linter_names(config)
     broken_linter_names = (set([i.name for i in config]) - set(working_linter_names))
     return working_linter_names, broken_linter_names
@@ -449,6 +449,16 @@ def run_linters(options, config, extras=[]):
 
     unlintable_filenames = set(all_filenames) - lintable_filenames
 
+    # Filter the linter config down to the selected ones.
+    if 'only' in options:
+        config = [linter for linter in config
+                  if linter.name in options['only']]
+    elif 'exclude' in options:
+        config = [linter for linter in config
+                  if linter.name not in options['exclude']]
+    if not len(config):
+        raise RuntimeError('No linters left to run! Be less strict with --only and --exclude.')
+
     working_linter_names, broken_linter_names = get_linter_status(config)
 
     cant_lint_filter = MatchFilter(build_config_subset(