yamllint version 1.32.0

Inspired be ESLint's search, it looks for configuration files in all
parent directories up until it reaches the user's home or root.

closes #571

CHANGELOG.rst

@@ -1,6 +1,12 @@
 Changelog
 =========
 
+1.32.0 (2023-05-22)
+-------------------
+
+- Look for configuration file in parent directories
+- Rule ``anchors``: add new option ``forbid-unused-anchors``
+
 1.31.0 (2023-04-21)
 -------------------
 

docs/configuration.rst

@@ -15,7 +15,8 @@ If ``-c`` is not provided, yamllint will look for a configuration file in the
 following locations (by order of preference):
 
 - a file named ``.yamllint``, ``.yamllint.yaml``, or ``.yamllint.yml`` in the
-  current working directory
+  current working directory, or a parent directory (the search for this file is
+  terminated at the user's home or filesystem root)
 - a filename referenced by ``$YAMLLINT_CONFIG_FILE``, if set
 - a file named ``$XDG_CONFIG_HOME/yamllint/config`` or
   ``~/.config/yamllint/config``, if present

tests/rules/test_anchors.py

@@ -80,7 +80,8 @@ class AnchorsTestCase(RuleTestCase):
     def test_forbid_undeclared_aliases(self):
         conf = ('anchors:\n'
                 '  forbid-undeclared-aliases: true\n'
-                '  forbid-duplicated-anchors: false\n')
+                '  forbid-duplicated-anchors: false\n'
+                '  forbid-unused-anchors: false\n')
         self.check('---\n'
                    '- &b true\n'
                    '- &i 42\n'
@@ -122,6 +123,7 @@ class AnchorsTestCase(RuleTestCase):
                    '- *f_m\n'
                    '- *f_s\n'  # declared after
                    '- &f_s [1, 2]\n'
+                   '...\n'
                    '---\n'
                    'block mapping: &b_m\n'
                    '  key: value\n'
@@ -141,13 +143,14 @@ class AnchorsTestCase(RuleTestCase):
                    problem3=(11, 3),
                    problem4=(12, 3),
                    problem5=(13, 3),
-                   problem6=(24, 7),
-                   problem7=(27, 37))
+                   problem6=(25, 7),
+                   problem7=(28, 37))
 
     def test_forbid_duplicated_anchors(self):
         conf = ('anchors:\n'
                 '  forbid-undeclared-aliases: false\n'
-                '  forbid-duplicated-anchors: true\n')
+                '  forbid-duplicated-anchors: true\n'
+                '  forbid-unused-anchors: false\n')
         self.check('---\n'
                    '- &b true\n'
                    '- &i 42\n'
@@ -189,6 +192,7 @@ class AnchorsTestCase(RuleTestCase):
                    '- *f_m\n'
                    '- *f_s\n'  # declared after
                    '- &f_s [1, 2]\n'
+                   '...\n'
                    '---\n'
                    'block mapping: &b_m\n'
                    '  key: value\n'
@@ -205,5 +209,73 @@ class AnchorsTestCase(RuleTestCase):
                    '...\n', conf,
                    problem1=(5, 3),
                    problem2=(6, 3),
-                   problem3=(21, 18),
-                   problem4=(27, 20))
+                   problem3=(22, 18),
+                   problem4=(28, 20))
+
+    def test_forbid_unused_anchors(self):
+        conf = ('anchors:\n'
+                '  forbid-undeclared-aliases: false\n'
+                '  forbid-duplicated-anchors: false\n'
+                '  forbid-unused-anchors: true\n')
+
+        self.check('---\n'
+                   '- &b true\n'
+                   '- &i 42\n'
+                   '- &s hello\n'
+                   '- &f_m {k: v}\n'
+                   '- &f_s [1, 2]\n'
+                   '- *b\n'
+                   '- *i\n'
+                   '- *s\n'
+                   '- *f_m\n'
+                   '- *f_s\n'
+                   '---\n'  # redeclare anchors in a new document
+                   '- &b true\n'
+                   '- &i 42\n'
+                   '- &s hello\n'
+                   '- *b\n'
+                   '- *i\n'
+                   '- *s\n'
+                   '---\n'
+                   'block mapping: &b_m\n'
+                   '  key: value\n'
+                   'extended:\n'
+                   '  <<: *b_m\n'
+                   '  foo: bar\n'
+                   '---\n'
+                   '{a: 1, &x b: 2, c: &y 3, *x : 4, e: *y}\n'
+                   '...\n', conf)
+        self.check('---\n'
+                   '- &i 42\n'
+                   '---\n'
+                   '- &b true\n'
+                   '- &b true\n'
+                   '- &b true\n'
+                   '- &s hello\n'
+                   '- *b\n'
+                   '- *i\n'    # declared in a previous document
+                   '- *f_m\n'  # never declared
+                   '- *f_m\n'
+                   '- *f_m\n'
+                   '- *f_s\n'  # declared after
+                   '- &f_s [1, 2]\n'
+                   '...\n'
+                   '---\n'
+                   'block mapping: &b_m\n'
+                   '  key: value\n'
+                   '---\n'
+                   'block mapping 1: &b_m_bis\n'
+                   '  key: value\n'
+                   'block mapping 2: &b_m_bis\n'
+                   '  key: value\n'
+                   'extended:\n'
+                   '  <<: *b_m\n'
+                   '  foo: bar\n'
+                   '---\n'
+                   '{a: 1, &x b: 2, c: &x 3, *x : 4, e: *y}\n'
+                   '...\n', conf,
+                   problem1=(2, 3),
+                   problem2=(7, 3),
+                   problem3=(14, 3),
+                   problem4=(17, 16),
+                   problem5=(22, 18))

tests/test_cli.py

@@ -734,3 +734,64 @@ class CommandLineConfigTestCase(unittest.TestCase):
 
                 self.assertEqual((ctx.returncode, ctx.stdout, ctx.stderr),
                                  (0, '', ''))
+
+    def test_parent_config_file(self):
+        workspace = {'a/b/c/d/e/f/g/a.yml': 'hello: world\n'}
+        conf = ('---\n'
+                'extends: relaxed\n')
+
+        for conf_file in ('.yamllint', '.yamllint.yml', '.yamllint.yaml'):
+            with self.subTest(conf_file):
+                with temp_workspace(workspace):
+                    with RunContext(self) as ctx:
+                        os.chdir('a/b/c/d/e/f')
+                        cli.run(('-f', 'parsable', '.'))
+
+                self.assertEqual((ctx.returncode, ctx.stdout, ctx.stderr),
+                                 (0, './g/a.yml:1:1: [warning] missing '
+                                     'document start "---" (document-start)\n',
+                                     ''))
+
+                with temp_workspace({**workspace, **{conf_file: conf}}):
+                    with RunContext(self) as ctx:
+                        os.chdir('a/b/c/d/e/f')
+                        cli.run(('-f', 'parsable', '.'))
+
+                self.assertEqual((ctx.returncode, ctx.stdout, ctx.stderr),
+                                 (0, '', ''))
+
+    def test_multiple_parent_config_file(self):
+        workspace = {'a/b/c/3spaces.yml': 'array:\n'
+                                          '   - item\n',
+                     'a/b/c/4spaces.yml': 'array:\n'
+                                          '    - item\n',
+                     'a/.yamllint': '---\n'
+                                    'extends: relaxed\n'
+                                    'rules:\n'
+                                    '  indentation:\n'
+                                    '    spaces: 4\n',
+                     }
+
+        conf3 = ('---\n'
+                 'extends: relaxed\n'
+                 'rules:\n'
+                 '  indentation:\n'
+                 '    spaces: 3\n')
+
+        with temp_workspace(workspace):
+            with RunContext(self) as ctx:
+                os.chdir('a/b/c')
+                cli.run(('-f', 'parsable', '.'))
+
+        self.assertEqual((ctx.returncode, ctx.stdout, ctx.stderr),
+                         (0, './3spaces.yml:2:4: [warning] wrong indentation: '
+                         'expected 4 but found 3 (indentation)\n', ''))
+
+        with temp_workspace({**workspace, **{'a/b/.yamllint.yml': conf3}}):
+            with RunContext(self) as ctx:
+                os.chdir('a/b/c')
+                cli.run(('-f', 'parsable', '.'))
+
+        self.assertEqual((ctx.returncode, ctx.stdout, ctx.stderr),
+                         (0, './4spaces.yml:2:5: [warning] wrong indentation: '
+                         'expected 3 but found 4 (indentation)\n', ''))

yamllint/__init__.py

@@ -21,7 +21,7 @@ indentation, etc."""
 
 
 APP_NAME = 'yamllint'
-APP_VERSION = '1.31.0'
+APP_VERSION = '1.32.0'
 APP_DESCRIPTION = __doc__
 
 __author__ = 'Adrien Vergé'

yamllint/cli.py

@@ -141,6 +141,19 @@ def show_problems(problems, file, args_format, no_warn):
     return max_level
 
 
+def find_project_config_filepath(path='.'):
+    for filename in ('.yamllint', '.yamllint.yaml', '.yamllint.yml'):
+        filepath = os.path.join(path, filename)
+        if os.path.isfile(filepath):
+            return filepath
+
+    if os.path.abspath(path) == os.path.abspath(os.path.expanduser('~')):
+        return None
+    if os.path.abspath(path) == os.path.abspath(os.path.join(path, '..')):
+        return None
+    return find_project_config_filepath(path=os.path.join(path, '..'))
+
+
 def run(argv=None):
     parser = argparse.ArgumentParser(prog=APP_NAME,
                                      description=APP_DESCRIPTION)
@@ -185,6 +198,7 @@ def run(argv=None):
     else:
         user_global_config = os.path.expanduser('~/.config/yamllint/config')
 
+    project_config_filepath = find_project_config_filepath()
     try:
         if args.config_data is not None:
             if args.config_data != '' and ':' not in args.config_data:
@@ -192,12 +206,8 @@ def run(argv=None):
             conf = YamlLintConfig(content=args.config_data)
         elif args.config_file is not None:
             conf = YamlLintConfig(file=args.config_file)
-        elif os.path.isfile('.yamllint'):
-            conf = YamlLintConfig(file='.yamllint')
-        elif os.path.isfile('.yamllint.yaml'):
-            conf = YamlLintConfig(file='.yamllint.yaml')
-        elif os.path.isfile('.yamllint.yml'):
-            conf = YamlLintConfig(file='.yamllint.yml')
+        elif project_config_filepath:
+            conf = YamlLintConfig(file=project_config_filepath)
         elif os.path.isfile(user_global_config):
             conf = YamlLintConfig(file=user_global_config)
         else:

yamllint/rules/anchors.py

@@ -24,6 +24,8 @@ anchors.
   later in the document).
 * Set ``forbid-duplicated-anchors`` to ``true`` to avoid duplications of a same
   anchor.
+* Set ``forbid-unused-anchors`` to ``true`` to avoid anchors being declared but
+  not used anywhere in the YAML document via alias.
 
 .. rubric:: Default values (when enabled)
 
@@ -33,6 +35,7 @@ anchors.
    anchors:
      forbid-undeclared-aliases: true
      forbid-duplicated-anchors: false
+     forbid-unused-anchors: false
 
 .. rubric:: Examples
 
@@ -78,6 +81,26 @@ anchors.
     ---
     - &anchor Foo Bar
     - &anchor [item 1, item 2]
+
+#. With ``anchors: {forbid-unused-anchors: true}``
+
+   the following code snippet would **PASS**:
+   ::
+
+    ---
+    - &anchor
+      foo: bar
+    - *anchor
+
+   the following code snippet would **FAIL**:
+   ::
+
+    ---
+    - &anchor
+      foo: bar
+    - items:
+      - item1
+      - item2
 """
 
 
@@ -89,15 +112,22 @@ from yamllint.linter import LintProblem
 ID = 'anchors'
 TYPE = 'token'
 CONF = {'forbid-undeclared-aliases': bool,
-        'forbid-duplicated-anchors': bool}
+        'forbid-duplicated-anchors': bool,
+        'forbid-unused-anchors': bool}
 DEFAULT = {'forbid-undeclared-aliases': True,
-           'forbid-duplicated-anchors': False}
+           'forbid-duplicated-anchors': False,
+           'forbid-unused-anchors': False}
 
 
 def check(conf, token, prev, next, nextnext, context):
-    if conf['forbid-undeclared-aliases'] or conf['forbid-duplicated-anchors']:
-        if isinstance(token, (yaml.StreamStartToken, yaml.DocumentStartToken)):
-            context['anchors'] = set()
+    if (conf['forbid-undeclared-aliases'] or
+            conf['forbid-duplicated-anchors'] or
+            conf['forbid-unused-anchors']):
+        if isinstance(token, (
+                yaml.StreamStartToken,
+                yaml.DocumentStartToken,
+                yaml.DocumentEndToken)):
+            context['anchors'] = {}
 
     if (conf['forbid-undeclared-aliases'] and
             isinstance(token, yaml.AliasToken) and
@@ -113,6 +143,32 @@ def check(conf, token, prev, next, nextnext, context):
             token.start_mark.line + 1, token.start_mark.column + 1,
             f'found duplicated anchor "{token.value}"')
 
-    if conf['forbid-undeclared-aliases'] or conf['forbid-duplicated-anchors']:
+    if conf['forbid-unused-anchors']:
+        # Unused anchors can only be detected at the end of Document.
+        # End of document can be either
+        #   - end of stream
+        #   - end of document sign '...'
+        #   - start of a new document sign '---'
+        # If next token indicates end of document,
+        # check if the anchors have been used or not.
+        # If they haven't been used, report problem on those anchors.
+        if isinstance(next, (yaml.StreamEndToken,
+                             yaml.DocumentStartToken,
+                             yaml.DocumentEndToken)):
+            for anchor, info in context['anchors'].items():
+                if not info['used']:
+                    yield LintProblem(info['line'] + 1,
+                                      info['column'] + 1,
+                                      f'found unused anchor "{anchor}"')
+        elif isinstance(token, yaml.AliasToken):
+            context['anchors'].get(token.value, {})['used'] = True
+
+    if (conf['forbid-undeclared-aliases'] or
+            conf['forbid-duplicated-anchors'] or
+            conf['forbid-unused-anchors']):
         if isinstance(token, yaml.AnchorToken):
-            context['anchors'].add(token.value)
+            context['anchors'][token.value] = {
+                'line': token.start_mark.line,
+                'column': token.start_mark.column,
+                'used': False
+            }