fix: ignore-from-file relative to config file

docs/configuration.rst

@@ -227,6 +227,7 @@ or:
  ignore-from-file: [.gitignore, .yamlignore]
 
 .. note:: However, this is mutually exclusive with the ``ignore`` key.
+          Also, this filepath is considered relative to the config file.
 
 If you need to know the exact list of files that yamllint would process,
 without really linting them, you can use ``--list-files``:

tests/test_config.py

@@ -498,6 +498,29 @@ def test_ignore_from_file_not_exist(self):
             config.YamlLintConfig, 'extends: default\n'
                                    'ignore-from-file: not_found_file\n')
 
+    def test_ignore_from_file_exist(self):
+        with open(os.path.join(self.wd, '.gitignore'), 'w') as f:
+            f.write('*.dont-lint-me.yaml\n'
+                    '/bin/\n'
+                    '!/bin/*.lint-me-anyway.yaml\n')
+        parsed = config.YamlLintConfig('extends: default\n'
+                              'ignore-from-file: .gitignore\n')
+        assert parsed.is_file_ignored("/bin/ignored") is True
+
+    def test_ignore_from_file_from_subdir_fails_without_config_file(self):
+        with open(os.path.join(self.wd, '.gitignore'), 'w') as f:
+            f.write('*.dont-lint-me.yaml\n'
+                    '/bin/\n'
+                    '!/bin/*.lint-me-anyway.yaml\n')
+        try:
+            os.chdir(os.path.join(self.wd, 'bin'))
+            self.assertRaises(
+                FileNotFoundError,
+                config.YamlLintConfig, 'extends: default\n'
+                                    'ignore-from-file: .gitignore\n')
+        finally:
+            os.chdir(self.wd)
+
     def test_ignore_from_file_incorrect_type(self):
         self.assertRaises(
             YamlLintConfigError,
@@ -721,6 +744,74 @@ def test_run_with_ignore_from_file(self):
             './s/s/ign-trail/s/s/file2.lint-me-anyway.yaml:5:5: ' + hyphen,
         )))
 
+    def test_run_in_subdir_with_ignore_from_file(self):
+        with open(os.path.join(self.wd, '.yamllint'), 'w') as f:
+            f.write('extends: default\n'
+                    'ignore-from-file: .gitignore\n'
+                    'rules:\n'
+                    '  key-duplicates:\n'
+                    '    ignore-from-file: .ignore-key-duplicates\n')
+
+        with open(os.path.join(self.wd, '.gitignore'), 'w') as f:
+            f.write('*.dont-lint-me.yaml\n'
+                    '/bin/\n'
+                    '!/bin/*.lint-me-anyway.yaml\n')
+
+        with open(os.path.join(self.wd, '.ignore-key-duplicates'), 'w') as f:
+            f.write('/ign-dup\n')
+
+        sys.stdout = StringIO()
+        try:
+            os.chdir(os.path.join(self.wd, 'bin'))
+            with self.assertRaises(SystemExit):
+                cli.run(('-f', 'parsable', '.'))
+        finally:
+            os.chdir(self.wd)
+
+        out = sys.stdout.getvalue()
+        out = '\n'.join(sorted(out.splitlines()))
+
+        keydup = '[error] duplication of key "key" in mapping (key-duplicates)'
+        trailing = '[error] trailing spaces (trailing-spaces)'
+        hyphen = '[error] too many spaces after hyphen (hyphens)'
+
+        self.assertEqual(out, '\n'.join((
+            './file.lint-me-anyway.yaml:3:3: ' + keydup,
+            './file.lint-me-anyway.yaml:4:17: ' + trailing,
+            './file.lint-me-anyway.yaml:5:5: ' + hyphen,
+        )))
+
+    def test_run_in_subdir_with_ignore_from_file_in_subdir(self):
+        if os.path.exists(os.path.join(self.wd, '.gitignore')):
+            os.remove(os.path.join(self.wd, '.gitignore'))
+        with open(os.path.join(self.wd, '.yamllint'), 'w') as f:
+            f.write('extends: default\n'
+                    'ignore-from-file: .gitignore\n'
+                    'rules:\n'
+                    '  key-duplicates:\n'
+                    '    ignore-from-file: .ignore-key-duplicates\n')
+
+        with open(os.path.join(self.wd, 'bin', '.gitignore'), 'w') as f:
+            f.write('*.dont-lint-me.yaml\n'
+                    '/bin/\n'
+                    '!/bin/*.lint-me-anyway.yaml\n')
+
+        with open(os.path.join(self.wd, '.ignore-key-duplicates'), 'w') as f:
+            f.write('/ign-dup\n')
+
+        sys.stdout = StringIO()
+        sys.stderr = StringIO()
+        try:
+            os.chdir(os.path.join(self.wd, 'bin'))
+            with self.assertRaises(FileNotFoundError):
+                cli.run(('-f', 'parsable', '.'))
+        finally:
+            os.chdir(self.wd)
+
+        out = sys.stdout.getvalue()
+
+        self.assertEqual(out, '')
+
     def test_run_with_ignored_from_file(self):
         with open(os.path.join(self.wd, '.yamllint'), 'w') as f:
             f.write('ignore-from-file: [.gitignore, .yamlignore]\n'

yamllint/config.py

@@ -31,20 +31,24 @@ def __init__(self, content=None, file=None):
         assert (content is None) ^ (file is None)
 
         self.ignore = None
+        self.config_dir = None
 
         self.yaml_files = pathspec.PathSpec.from_lines(
             'gitwildmatch', ['*.yaml', '*.yml', '.yamllint'])
 
         self.locale = None
 
         if file is not None:
+            self.config_dir = os.path.dirname(file)
             with open(file) as f:
                 content = f.read()
 
         self.parse(content)
         self.validate()
 
     def is_file_ignored(self, filepath):
+        if self.config_dir:
+            filepath = os.path.relpath(filepath, start=self.config_dir)
         return self.ignore and self.ignore.match_file(filepath)
 
     def is_yaml_file(self, filepath):
@@ -109,6 +113,11 @@ def parse(self, raw_content):
                 raise YamlLintConfigError(
                     'invalid config: ignore-from-file should contain '
                     'filename(s), either as a list or string')
+            if self.config_dir is not None:
+                conf['ignore-from-file'] = [
+                    f if os.path.basename(f) != f
+                    else os.path.join(self.config_dir, f)
+                    for f in conf['ignore-from-file']]
             with fileinput.input(conf['ignore-from-file']) as f:
                 self.ignore = pathspec.PathSpec.from_lines('gitwildmatch', f)
         elif 'ignore' in conf:
@@ -145,10 +154,12 @@ def validate(self):
             except Exception as e:
                 raise YamlLintConfigError(f'invalid config: {e}') from e
 
-            self.rules[id] = validate_rule_conf(rule, self.rules[id])
+            self.rules[id] = validate_rule_conf(rule,
+                                                self.rules[id],
+                                                self.config_dir)
 
 
-def validate_rule_conf(rule, conf):
+def validate_rule_conf(rule, conf, config_dir=None):
     if conf is False:  # disable
         return False
 
@@ -163,6 +174,11 @@ def validate_rule_conf(rule, conf):
                 raise YamlLintConfigError(
                     'invalid config: ignore-from-file should contain '
                     'valid filename(s), either as a list or string')
+            if config_dir is not None:
+                conf['ignore-from-file'] = [
+                    f if os.path.basename(f) != f
+                    else os.path.join(config_dir, f)
+                    for f in conf['ignore-from-file']]
             with fileinput.input(conf['ignore-from-file']) as f:
                 conf['ignore'] = pathspec.PathSpec.from_lines(
                     'gitwildmatch', f)