yamllint version 1.31.0

Using `setup.py` is deprecated and the new recommanded way is to declare
a `pyproject.toml` file (see PEP 517 [^1]).

This commit proposes to use setuptools to achieve that, because
setuptools is already used by yamllint, is standard and referenced by
the official Python packaging documentation [^2], and seems to be the
most lightweight solution. An alternative could have been to use Poetry,
see the dedicated pull request and discussion [^3].

For some period, the `setup.py` file will be kept (although almost
empty), to allow old tools versions to keep working.

Closes https://github.com/adrienverge/yamllint/issues/509.

[^1]: https://peps.python.org/pep-0517/
[^2]: https://packaging.python.org/en/latest/tutorials/installing-packages/
[^3]: https://github.com/adrienverge/yamllint/pull/557

.flake8

@@ -0,0 +1,4 @@
+[flake8]
+import-order-style = pep8
+application-import-names = yamllint
+ignore = W503,W504

.github/workflows/ci.yaml

@@ -8,24 +8,28 @@ on:  # yamllint disable-line rule:truthy
     branches:
       - master
 
+permissions:
+  contents: read
+
 jobs:
   lint:
     name: Linters
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
       - name: Set up Python
-        uses: actions/setup-python@v2
+        uses: actions/setup-python@v4
       - run:
-          python -m pip install flake8 flake8-import-order doc8 sphinx
+          pip install flake8 flake8-import-order sphinx rstcheck[sphinx] doc8
-            rstcheck[sphinx]
+      - run: pip install .
-      - run: python -m pip install .
       - run: flake8 .
       - run: doc8 $(git ls-files '*.rst')
       - run: rstcheck --ignore-directives automodule $(git ls-files '*.rst')
       - run: yamllint --strict $(git ls-files '*.yaml' '*.yml')
-      - run: python setup.py build_sphinx
+      - run: make -C docs html
+      - name: Check for broken links in documentation
+        run: make -C docs linkcheck
 
   test:
     name: Tests
@@ -34,22 +38,24 @@ jobs:
       fail-fast: false
       matrix:
         python-version:
-          - '3.6'
           - '3.7'
           - '3.8'
           - '3.9'
           - '3.10'
+          - '3.11'
     steps:
       - name: Checkout
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
       - name: Set up Python ${{ matrix.python-version }}
-        uses: actions/setup-python@v2
+        uses: actions/setup-python@v4
         with:
           python-version: ${{ matrix.python-version }}
       - name: Append GitHub Actions system path
         run: echo "$HOME/.local/bin" >> $GITHUB_PATH
-      - run: pip install coveralls
+      - run: pip install coverage
       - run: pip install .
-      - run: coverage run --source=yamllint -m unittest discover
+      # https://github.com/AndreMiras/coveralls-python-action/issues/18
+      - run: echo -e "[run]\nrelative_files = True" > .coveragerc
+      - run: coverage run -m unittest discover
       - name: Coveralls
         uses: AndreMiras/coveralls-python-action@develop

CHANGELOG.rst

@@ -1,6 +1,48 @@
 Changelog
 =========
 
+1.31.0 (2023-04-21)
+-------------------
+
+- Build: migrate from ``setup.py`` to ``pyproject.toml``
+- Docs: update some outdated URLs
+- Rule ``colons``: prevent error when space before is mandatory
+
+1.30.0 (2023-03-22)
+-------------------
+
+- Rule ``anchors``: add new rule to detect undeclared or duplicated anchors
+- Python API: prevent using ``is_file_ignored()`` with null ``filepath``
+- Docs: fix misleading Python API example
+- Docs: fix plain text code snippet example
+- Docs: update pre-commit hook example
+
+1.29.0 (2023-01-10)
+-------------------
+
+- Add support for Python 3.11, drop support for Python 3.6
+- Rule ``float-values``: fix bug on strings containing fordidden values
+- Stop releasing universal wheels
+- Use proper Python 3 I/O type for file reading
+- Rule ``indentation``: fix ``indent-sequences`` in nested collections
+- Docs: clarify ``disable-line`` and parser errors, give a workaround
+- Refactors to apply some pyupgrade suggestions
+- Allow using a list of strings in ``ignore`` configuration
+- Add ``--list-files`` command line option
+
+1.28.0 (2022-09-12)
+-------------------
+
+- Better compress PNG image in documentation
+- Remove ``__future__`` imports specific to Python 2
+- Remove inheritance from ``object`` specific to Python 2
+- Simplify GitHub Actions example in documentation
+- Update ALE vim plugin link in documentation
+- Update license to latest version of GPLv3
+- Pre-compile disable/enable rules regexes
+- Rule ``quoted-strings``: add ``allow-quoted-quotes`` option
+- Add option ``ignore-from-file`` in config
+
 1.27.1 (2022-07-08)
 -------------------
 
@@ -14,7 +56,7 @@ Changelog
 - Refactor ``--format=auto`` logic
 - Update GitHub format output to use groups
 - Rule ``comments``: allow whitespace after the shebang marker
-- Multiple minor fixes in documetation
+- Multiple minor fixes in documentation
 - Configure Sphinx to make man page show up in apropos
 - Attempt to clarify configuration file location in documentation
 - Rule ``key-duplicates``: don't crash on redundant closing brackets or braces

LICENSE

@@ -1,7 +1,7 @@
                     GNU GENERAL PUBLIC LICENSE
                        Version 3, 29 June 2007
 
- Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
+ Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
  Everyone is permitted to copy and distribute verbatim copies
  of this license document, but changing it is not allowed.
 
@@ -645,7 +645,7 @@ the "copyright" line and a pointer to where the full notice is found.
     GNU General Public License for more details.
 
     You should have received a copy of the GNU General Public License
-    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 Also add information on how to contact you by electronic and paper mail.
 
@@ -664,11 +664,11 @@ might be different; for a GUI interface, you would use an "about box".
   You should also get your employer (if you work as a programmer) or school,
 if any, to sign a "copyright disclaimer" for the program, if necessary.
 For more information on this, and how to apply and follow the GNU GPL, see
-<http://www.gnu.org/licenses/>.
+<https://www.gnu.org/licenses/>.
 
   The GNU General Public License does not permit incorporating your program
 into proprietary programs.  If your program is a subroutine library, you
 may consider it more useful to permit linking proprietary applications with
 the library.  If this is what you want to do, use the GNU Lesser General
 Public License instead of this License.  But first, please read
-<http://www.gnu.org/philosophy/why-not-lgpl.html>.
+<https://www.gnu.org/licenses/why-not-lgpl.html>.

MANIFEST.in

@@ -1,4 +0,0 @@
-include LICENSE
-include README.rst
-include docs/*
-include tests/*.py tests/rules/*.py tests/yaml-1.2-spec-examples/*

README.rst

@@ -8,8 +8,8 @@ repetition and cosmetic problems such as lines length, trailing spaces,
 indentation, etc.
 
 .. image::
-   https://travis-ci.org/adrienverge/yamllint.svg?branch=master
+   https://github.com/adrienverge/yamllint/actions/workflows/ci.yaml/badge.svg?branch=master
-   :target: https://travis-ci.org/adrienverge/yamllint
+   :target: https://github.com/adrienverge/yamllint/actions/workflows/ci.yaml?query=branch%3Amaster
    :alt: CI tests status
 .. image::
    https://coveralls.io/repos/github/adrienverge/yamllint/badge.svg?branch=master

docs/Makefile

@@ -2,7 +2,7 @@
 #
 
 # You can set these variables from the command line.
-SPHINXOPTS    =
+SPHINXOPTS    = -W
 SPHINXBUILD   = sphinx-build
 PAPER         =
 BUILDDIR      = _build

docs/conf.py

@@ -38,7 +38,7 @@ htmlhelp_basename = 'yamllintdoc'
 # One entry per manual page. List of tuples
 # (source start file, name, description, authors, manual section).
 man_pages = [
-    ('index', 'yamllint', 'Linter for YAML files', [u'Adrien Vergé'], 1)
+    ('index', 'yamllint', 'Linter for YAML files', ['Adrien Vergé'], 1)
 ]
 
 # -- Build with sphinx automodule without needing to install third-party libs

docs/configuration.rst

@@ -136,11 +136,19 @@ directories, set ``yaml-files`` configuration option. The default is:
 The same rules as for ignoring paths apply (``.gitignore``-style path pattern,
 see below).
 
+If you need to know the exact list of files that yamllint would process,
+without really linting them, you can use ``--list-files``:
+
+.. code:: bash
+
+ yamllint --list-files .
+
 Ignoring paths
 --------------
 
 It is possible to exclude specific files or directories, so that the linter
-doesn't process them.
+doesn't process them. They can be provided either as a list of paths, or as a
+bulk string.
 
 You can either totally ignore files (they won't be looked at):
 
@@ -153,6 +161,13 @@ You can either totally ignore files (they won't be looked at):
    all/this/directory/
    *.template.yaml
 
+ # or:
+
+ ignore:
+   - /this/specific/file.yaml
+   - all/this/directory/
+   - '*.template.yaml'
+
 or ignore paths only for specific rules:
 
 .. code-block:: yaml
@@ -165,10 +180,18 @@ or ignore paths only for specific rules:
        /this-file-has-trailing-spaces-but-it-is-OK.yaml
        /generated/*.yaml
 
+ # or:
+
+ rules:
+   trailing-spaces:
+     ignore:
+       - /this-file-has-trailing-spaces-but-it-is-OK.yaml
+       - /generated/*.yaml
+
 Note that this ``.gitignore``-style path pattern allows complex path
 exclusion/inclusion, see the `pathspec README file
-<https://pypi.python.org/pypi/pathspec>`_ for more details.
+<https://pypi.org/project/pathspec/>`_ for more details. Here is a more complex
-Here is a more complex example:
+example:
 
 .. code-block:: yaml
 
@@ -190,6 +213,27 @@ Here is a more complex example:
        *.ignore-trailing-spaces.yaml
        ascii-art/*
 
+You can also use the ``.gitignore`` file (or any list of files) through:
+
+.. code-block:: yaml
+
+ ignore-from-file: .gitignore
+
+or:
+
+.. code-block:: yaml
+
+ ignore-from-file: [.gitignore, .yamlignore]
+
+.. note:: However, this is mutually exclusive with the ``ignore`` key.
+
+If you need to know the exact list of files that yamllint would process,
+without really linting them, you can use ``--list-files``:
+
+.. code:: bash
+
+ yamllint --list-files .
+
 Setting the locale
 ------------------
 

docs/development.rst

@@ -11,7 +11,7 @@ Basic example of running the linter from Python:
    import yamllint
 
    yaml_config = yamllint.config.YamlLintConfig("extends: default")
-   for p in yamllint.linter.run("example.yaml", yaml_config):
+   for p in yamllint.linter.run(open("example.yaml", "r"), yaml_config):
        print(p.desc, p.line, p.rule)
 
 .. automodule:: yamllint.linter

docs/disable_with_comments.rst

@@ -40,6 +40,11 @@ specific line:
  # yamllint disable-line
  -  {    all : rules ,are disabled   for this line}
 
+You can't make yamllint ignore invalid YAML syntax on a line (which generates a
+`syntax error`), such as when templating a YAML file with Jinja. In some cases,
+you can workaround this by putting the templating syntax in a YAML comment. See
+`Putting template flow control in comments`_.
+
 If you need to disable multiple rules, it is allowed to chain rules like this:
 ``# yamllint disable-line rule:hyphens rule:commas rule:indentation``.
 
@@ -89,7 +94,6 @@ For instance:
  key: value 2
 
  - This line is waaaaaaaaaay too long but yamllint will not report anything about it.
-   This line will be checked by yamllint.
 
 or:
 
@@ -101,3 +105,32 @@ or:
  key1: value1
  {% endif %}
  key2: value2
+
+Putting template flow control in comments
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Alternatively for templating you can wrap the template statements in comments
+to make it a valid YAML file. As long as the templating language doesn't use
+the same comment symbol, it should be a valid template and valid YAML (pre and
+post-template processing).
+
+Example of a Jinja2 code that cannot be parsed as YAML because it contains
+invalid tokens ``{%`` and ``%}``:
+
+.. code-block:: text
+
+ # This file IS NOT valid YAML and will produce syntax errors
+ {% if extra_info %}
+ key1: value1
+ {% endif %}
+ key2: value2
+
+But it can be fixed using YAML comments:
+
+.. code-block:: yaml
+
+ # This file IS valid YAML because the Jinja is in a YAML comment
+ # {% if extra_info %}
+ key1: value1
+ # {% endif %}
+ key2: value2

docs/index.rst

@@ -11,7 +11,7 @@ Screenshot
 
 .. note::
 
-   The default output format is inspired by `eslint <http://eslint.org/>`_, a
+   The default output format is inspired by `eslint <https://eslint.org/>`_, a
    great linting tool for Javascript.
 
 Table of contents

docs/integration.rst

@@ -4,7 +4,7 @@ Integration with other software
 Integration with pre-commit
 ---------------------------
 
-You can integrate yamllint in `pre-commit <http://pre-commit.com/>`_ tool.
+You can integrate yamllint in the `pre-commit <https://pre-commit.com/>`_ tool.
 Here is an example, to add in your .pre-commit-config.yaml
 
 .. code:: yaml
@@ -12,39 +12,34 @@ Here is an example, to add in your .pre-commit-config.yaml
   ---
   # Update the rev variable with the release version that you want, from the yamllint repo
   # You can pass your custom .yamllint with args attribute.
-  - repo: https://github.com/adrienverge/yamllint.git
+  repos:
-    rev: v1.17.0
+    - repo: https://github.com/adrienverge/yamllint.git
-    hooks:
+      rev: v1.29.0
-      - id: yamllint
+      hooks:
-        args: [-c=/path/to/.yamllint]
+        - id: yamllint
+          args: [--strict, -c=/path/to/.yamllint]
+
 
 Integration with GitHub Actions
 -------------------------------
 
 yamllint auto-detects when it's running inside of `GitHub
-Actions <https://github.com/features/actions>`_ and automatically uses the suited
+Actions <https://github.com/features/actions>`_ and automatically uses the
-output format to decorate code with linting errors. You can also force the
+suited output format to decorate code with linting errors. You can also force
-GitHub Actions output with ``yamllint --format github``.
+the GitHub Actions output with ``yamllint --format github``.
 
-An example workflow using GitHub Actions:
+A minimal example workflow using GitHub Actions:
 
 .. code:: yaml
 
    ---
-   name: yamllint test
+   on: push  # yamllint disable-line rule:truthy
-
-   on: push
 
    jobs:
-     test:
+     lint:
        runs-on: ubuntu-latest
        steps:
-         - uses: actions/checkout@v2
+         - uses: actions/checkout@v3
-
-         - name: Set up Python
-           uses: actions/setup-python@v2
-           with:
-             python-version: 3.8
 
          - name: Install yamllint
            run: pip install yamllint

docs/quickstart.rst

@@ -4,7 +4,7 @@ Quickstart
 Installing yamllint
 -------------------
 
-On Fedora / CentOS (note: `EPEL <https://fedoraproject.org/wiki/EPEL>`_ is
+On Fedora / CentOS (note: `EPEL <https://docs.fedoraproject.org/en-US/epel/>`_ is
 required on CentOS):
 
 .. code:: bash
@@ -45,7 +45,7 @@ If you prefer installing from source, you can run, from the source directory:
 
 .. code:: bash
 
- python setup.py sdist
+ python -m build
  pip install --user dist/yamllint-*.tar.gz
 
 Running yamllint

docs/rules.rst

@@ -14,6 +14,11 @@ This page describes the rules and their options.
    :local:
    :depth: 1
 
+anchors
+-------
+
+.. automodule:: yamllint.rules.anchors
+
 braces
 ------
 

docs/text_editors.rst

@@ -9,11 +9,11 @@ text editor.
 Vim
 ---
 
-Assuming that the `ALE <https://github.com/w0rp/ale>`_ plugin is
+Assuming that the `ALE <https://github.com/dense-analysis/ale>`_ plugin is
 installed, yamllint is supported by default. It is automatically enabled when
 editing YAML files.
 
-If you instead use the `syntastic <https://github.com/scrooloose/syntastic>`_
+If you instead use the `syntastic <https://github.com/vim-syntastic/syntastic>`_
 plugin, add this to your ``.vimrc``:
 
 ::
@@ -23,7 +23,7 @@ plugin, add this to your ``.vimrc``:
 Neovim
 ------
 
-Assuming that the `neomake <https://github.com/benekastah/neomake>`_ plugin is
+Assuming that the `neomake <https://github.com/neomake/neomake>`_ plugin is
 installed, yamllint is supported by default. It is automatically enabled when
 editing YAML files.
 

pyproject.toml

@@ -0,0 +1,54 @@
+[project]
+name = "yamllint"
+description = "A linter for YAML files."
+readme = {file = "README.rst", content-type = "text/x-rst"}
+requires-python = ">=3.7"
+license = {text = "GPL-3.0-only"}
+authors = [{name = "Adrien Vergé"}]
+keywords = ["yaml", "lint", "linter", "syntax", "checker"]
+classifiers = [
+    "Development Status :: 5 - Production/Stable",
+    "Environment :: Console",
+    "Intended Audience :: Developers",
+    "License :: OSI Approved :: GNU General Public License v3 (GPLv3)",
+    "Programming Language :: Python",
+    "Topic :: Software Development",
+    "Topic :: Software Development :: Debuggers",
+    "Topic :: Software Development :: Quality Assurance",
+    "Topic :: Software Development :: Testing",
+]
+dependencies = [
+    "pathspec >= 0.5.3",
+    "pyyaml",
+]
+dynamic = ["version"]
+
+[project.optional-dependencies]
+dev = [
+    "doc8",
+    "flake8",
+    "flake8-import-order",
+    "rstcheck[sphinx]",
+    "sphinx",
+]
+
+[project.scripts]
+yamllint = "yamllint.cli:run"
+
+[project.urls]
+homepage = "https://github.com/adrienverge/yamllint"
+repository = "https://github.com/adrienverge/yamllint"
+documentation = "https://yamllint.readthedocs.io"
+
+[build-system]
+build-backend = "setuptools.build_meta"
+requires = ["setuptools >= 61"]
+
+[tool.setuptools]
+packages = ["yamllint", "yamllint.conf", "yamllint.rules"]
+
+[tool.setuptools.package-data]
+yamllint = ["conf/*.yaml"]
+
+[tool.setuptools.dynamic]
+version = {attr = "yamllint.__version__"}

setup.cfg

@@ -1,72 +0,0 @@
-[bdist_wheel]
-universal = 1
-
-[flake8]
-import-order-style = pep8
-application-import-names = yamllint
-ignore = W503,W504
-
-[build_sphinx]
-all-files = 1
-source-dir = docs
-build-dir = docs/_build
-warning-is-error = 1
-
-[metadata]
-keywords =
-  yaml
-  lint
-  linter
-  syntax
-  checker
-
-url = https://github.com/adrienverge/yamllint
-classifiers =
-  Development Status :: 5 - Production/Stable
-  Environment :: Console
-  Intended Audience :: Developers
-  License :: OSI Approved :: GNU General Public License v3 (GPLv3)
-  Programming Language :: Python :: 3
-  Programming Language :: Python :: 3.6
-  Programming Language :: Python :: 3.7
-  Programming Language :: Python :: 3.8
-  Programming Language :: Python :: 3.9
-  Programming Language :: Python :: 3.10
-  Topic :: Software Development
-  Topic :: Software Development :: Debuggers
-  Topic :: Software Development :: Quality Assurance
-  Topic :: Software Development :: Testing
-
-project_urls =
-  Documentation = https://yamllint.readthedocs.io
-  Download = https://pypi.org/project/yamllint/#files
-  Bug Tracker = https://github.com/adrienverge/yamllint/issues
-  Source Code = https://github.com/adrienverge/yamllint
-
-[options]
-packages = find:
-
-python_requires = >=3.6
-
-include_package_data = True
-install_requires =
-  pathspec >= 0.5.3
-  pyyaml
-  setuptools
-
-test_suite = tests
-
-[options.packages.find]
-exclude =
-  tests
-  tests.*
-
-[options.package_data]
-yamllint = conf/*.yaml
-
-[options.entry_points]
-console_scripts =
-  yamllint = yamllint.cli:run
-
-[coverage:run]
-relative_files = True

setup.py

@@ -15,15 +15,6 @@
 
 from setuptools import setup
 
-from yamllint import (__author__, __license__,
+# This is only kept for backward-compatibility with older versions that don't
-                      APP_NAME, APP_VERSION, APP_DESCRIPTION)
+# support new packaging standards (e.g. PEP 517 or PEP 660):
-
+setup()
-
-setup(
-    name=APP_NAME,
-    version=APP_VERSION,
-    author=__author__,
-    description=APP_DESCRIPTION.split('\n')[0],
-    long_description=APP_DESCRIPTION,
-    license=__license__,
-)

tests/rules/test_anchors.py

@@ -0,0 +1,209 @@
+# Copyright (C) 2023 Adrien Vergé
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+from tests.common import RuleTestCase
+
+
+class AnchorsTestCase(RuleTestCase):
+    rule_id = 'anchors'
+
+    def test_disabled(self):
+        conf = 'anchors: disable'
+        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'
+                   '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)
+
+    def test_forbid_undeclared_aliases(self):
+        conf = ('anchors:\n'
+                '  forbid-undeclared-aliases: true\n'
+                '  forbid-duplicated-anchors: false\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'
+                   '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=(9, 3),
+                   problem2=(10, 3),
+                   problem3=(11, 3),
+                   problem4=(12, 3),
+                   problem5=(13, 3),
+                   problem6=(24, 7),
+                   problem7=(27, 37))
+
+    def test_forbid_duplicated_anchors(self):
+        conf = ('anchors:\n'
+                '  forbid-undeclared-aliases: false\n'
+                '  forbid-duplicated-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'
+                   '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=(5, 3),
+                   problem2=(6, 3),
+                   problem3=(21, 18),
+                   problem4=(27, 20))

tests/rules/test_colons.py

@@ -256,3 +256,19 @@ class ColonTestCase(RuleTestCase):
                    '  property: {a: 1, b:  2, c : 3}\n', conf,
                    problem1=(3, 11), problem2=(4, 4),
                    problem3=(8, 23), problem4=(8, 28))
+
+    # Although accepted by PyYAML, `{*x: 4}` is not valid YAML: it should be
+    # noted `{*x : 4}`. The reason is that a colon can be part of an anchor
+    # name. See commit message for more details.
+    def test_with_alias_as_key(self):
+        conf = 'colons: {max-spaces-before: 0, max-spaces-after: 1}'
+        self.check('---\n'
+                   '- anchor: &a key\n'
+                   '- *a: 42\n'
+                   '- {*a: 42}\n'
+                   '- *a : 42\n'
+                   '- {*a : 42}\n'
+                   '- *a  : 42\n'
+                   '- {*a  : 42}\n',
+                   conf,
+                   problem1=(7, 6), problem2=(8, 7))

tests/rules/test_float_values.py

@@ -40,6 +40,8 @@ class FloatValuesTestCase(RuleTestCase):
                    '- 0.0\n'
                    '- .1\n'
                    '- \'.1\'\n'
+                   '- string.1\n'
+                   '- .1string\n'
                    '- !custom_tag .2\n'
                    '- &angle1 0.0\n'
                    '- *angle1\n'
@@ -47,7 +49,7 @@ class FloatValuesTestCase(RuleTestCase):
                    '- *angle2\n',
                    conf,
                    problem1=(3, 3),
-                   problem2=(8, 11))
+                   problem2=(10, 11))
 
     def test_scientific_notation(self):
         conf = (
@@ -61,6 +63,8 @@ class FloatValuesTestCase(RuleTestCase):
                    '- 10e-6\n'
                    '- 0.00001\n'
                    '- \'10e-6\'\n'
+                   '- string10e-6\n'
+                   '- 10e-6string\n'
                    '- !custom_tag 10e-6\n'
                    '- &angle1 0.000001\n'
                    '- *angle1\n'
@@ -71,8 +75,8 @@ class FloatValuesTestCase(RuleTestCase):
                    conf,
                    problem1=(2, 3),
                    problem2=(3, 3),
-                   problem3=(9, 11),
+                   problem3=(11, 11),
-                   problem4=(11, 11))
+                   problem4=(13, 11))
 
     def test_nan(self):
         conf = (
@@ -85,13 +89,15 @@ class FloatValuesTestCase(RuleTestCase):
                    '- .NaN\n'
                    '- .NAN\n'
                    '- \'.NaN\'\n'
+                   '- a.NaN\n'
+                   '- .NaNa\n'
                    '- !custom_tag .NaN\n'
                    '- &angle .nan\n'
                    '- *angle\n',
                    conf,
                    problem1=(2, 3),
                    problem2=(3, 3),
-                   problem3=(6, 10))
+                   problem3=(8, 10))
 
     def test_inf(self):
         conf = (
@@ -106,6 +112,8 @@ class FloatValuesTestCase(RuleTestCase):
                    '- -.inf\n'
                    '- -.INF\n'
                    '- \'.inf\'\n'
+                   '- ∞.infinity\n'
+                   '- .infinity∞\n'
                    '- !custom_tag .inf\n'
                    '- &angle .inf\n'
                    '- *angle\n'
@@ -116,5 +124,5 @@ class FloatValuesTestCase(RuleTestCase):
                    problem2=(3, 3),
                    problem3=(4, 3),
                    problem4=(5, 3),
-                   problem5=(8, 10),
+                   problem5=(10, 10),
-                   problem6=(10, 10))
+                   problem6=(12, 10))

tests/rules/test_indentation.py

@@ -1370,6 +1370,45 @@ class IndentationTestCase(RuleTestCase):
                    '               key: value\n'
                    '...\n', conf, problem=(2, 2))
 
+    def test_nested_collections_with_spaces_consistent(self):
+        """Tests behavior of {spaces: consistent} in nested collections to
+        ensure wrong-indentation is properly caught--especially when the
+        expected indent value is initially unknown. For details, see
+        https://github.com/adrienverge/yamllint/issues/485.
+        """
+        conf = ('indentation: {spaces: consistent,\n'
+                '              indent-sequences: true}')
+        self.check('---\n'
+                   '- item:\n'
+                   '  - elem\n'
+                   '- item:\n'
+                   '    - elem\n'
+                   '...\n', conf, problem=(3, 3))
+        conf = ('indentation: {spaces: consistent,\n'
+                '              indent-sequences: false}')
+        self.check('---\n'
+                   '- item:\n'
+                   '  - elem\n'
+                   '- item:\n'
+                   '    - elem\n'
+                   '...\n', conf, problem=(5, 5))
+        conf = ('indentation: {spaces: consistent,\n'
+                '              indent-sequences: consistent}')
+        self.check('---\n'
+                   '- item:\n'
+                   '  - elem\n'
+                   '- item:\n'
+                   '    - elem\n'
+                   '...\n', conf, problem=(5, 5))
+        conf = ('indentation: {spaces: consistent,\n'
+                '              indent-sequences: whatever}')
+        self.check('---\n'
+                   '- item:\n'
+                   '  - elem\n'
+                   '- item:\n'
+                   '    - elem\n'
+                   '...\n', conf)
+
     def test_return(self):
         conf = 'indentation: {spaces: consistent}'
         self.check('---\n'

tests/rules/test_quoted_strings.py

@@ -453,3 +453,106 @@ class QuotedTestCase(RuleTestCase):
                    '- "0o800"\n',
                    conf,
                    problem1=(9, 3), problem2=(10, 3))
+
+    def test_allow_quoted_quotes(self):
+        conf = ('quoted-strings: {quote-type: single,\n'
+                '                 required: false,\n'
+                '                 allow-quoted-quotes: false}\n')
+        self.check('---\n'
+                   'foo1: "[barbaz]"\n'          # fails
+                   'foo2: "[bar\'baz]"\n',       # fails
+                   conf, problem1=(2, 7), problem2=(3, 7))
+
+        conf = ('quoted-strings: {quote-type: single,\n'
+                '                 required: false,\n'
+                '                 allow-quoted-quotes: true}\n')
+        self.check('---\n'
+                   'foo1: "[barbaz]"\n'          # fails
+                   'foo2: "[bar\'baz]"\n',
+                   conf, problem1=(2, 7))
+
+        conf = ('quoted-strings: {quote-type: single,\n'
+                '                 required: true,\n'
+                '                 allow-quoted-quotes: false}\n')
+        self.check('---\n'
+                   'foo1: "[barbaz]"\n'          # fails
+                   'foo2: "[bar\'baz]"\n',       # fails
+                   conf, problem1=(2, 7), problem2=(3, 7))
+
+        conf = ('quoted-strings: {quote-type: single,\n'
+                '                 required: true,\n'
+                '                 allow-quoted-quotes: true}\n')
+        self.check('---\n'
+                   'foo1: "[barbaz]"\n'          # fails
+                   'foo2: "[bar\'baz]"\n',
+                   conf, problem1=(2, 7))
+
+        conf = ('quoted-strings: {quote-type: single,\n'
+                '                 required: only-when-needed,\n'
+                '                 allow-quoted-quotes: false}\n')
+        self.check('---\n'
+                   'foo1: "[barbaz]"\n'          # fails
+                   'foo2: "[bar\'baz]"\n',       # fails
+                   conf, problem1=(2, 7), problem2=(3, 7))
+
+        conf = ('quoted-strings: {quote-type: single,\n'
+                '                 required: only-when-needed,\n'
+                '                 allow-quoted-quotes: true}\n')
+        self.check('---\n'
+                   'foo1: "[barbaz]"\n'          # fails
+                   'foo2: "[bar\'baz]"\n',
+                   conf, problem1=(2, 7))
+
+        conf = ('quoted-strings: {quote-type: double,\n'
+                '                 required: false,\n'
+                '                 allow-quoted-quotes: false}\n')
+        self.check("---\n"
+                   "foo1: '[barbaz]'\n"          # fails
+                   "foo2: '[bar\"baz]'\n",       # fails
+                   conf, problem1=(2, 7), problem2=(3, 7))
+
+        conf = ('quoted-strings: {quote-type: double,\n'
+                '                 required: false,\n'
+                '                 allow-quoted-quotes: true}\n')
+        self.check("---\n"
+                   "foo1: '[barbaz]'\n"          # fails
+                   "foo2: '[bar\"baz]'\n",
+                   conf, problem1=(2, 7))
+
+        conf = ('quoted-strings: {quote-type: double,\n'
+                '                 required: true,\n'
+                '                 allow-quoted-quotes: false}\n')
+        self.check("---\n"
+                   "foo1: '[barbaz]'\n"          # fails
+                   "foo2: '[bar\"baz]'\n",       # fails
+                   conf, problem1=(2, 7), problem2=(3, 7))
+
+        conf = ('quoted-strings: {quote-type: double,\n'
+                '                 required: true,\n'
+                '                 allow-quoted-quotes: true}\n')
+        self.check("---\n"
+                   "foo1: '[barbaz]'\n"          # fails
+                   "foo2: '[bar\"baz]'\n",
+                   conf, problem1=(2, 7))
+
+        conf = ('quoted-strings: {quote-type: double,\n'
+                '                 required: only-when-needed,\n'
+                '                 allow-quoted-quotes: false}\n')
+        self.check("---\n"
+                   "foo1: '[barbaz]'\n"          # fails
+                   "foo2: '[bar\"baz]'\n",       # fails
+                   conf, problem1=(2, 7), problem2=(3, 7))
+
+        conf = ('quoted-strings: {quote-type: double,\n'
+                '                 required: only-when-needed,\n'
+                '                 allow-quoted-quotes: true}\n')
+        self.check("---\n"
+                   "foo1: '[barbaz]'\n"          # fails
+                   "foo2: '[bar\"baz]'\n",
+                   conf, problem1=(2, 7))
+
+        conf = ('quoted-strings: {quote-type: any}\n')
+        self.check("---\n"
+                   "foo1: '[barbaz]'\n"
+                   "foo2: '[bar\"baz]'\n",
+                   conf)

tests/test_cli.py

@@ -29,7 +29,7 @@ from yamllint import cli
 from yamllint import config
 
 
-class RunContext(object):
+class RunContext:
     """Context manager for ``cli.run()`` to capture exit code and streams."""
 
     def __init__(self, case):
@@ -92,12 +92,12 @@ class CommandLineTestCase(unittest.TestCase):
             'no-yaml.json': '---\n'
                             'key: value\n',
             # non-ASCII chars
-            u'non-ascii/éçäγλνπ¥/utf-8': (
+            'non-ascii/éçäγλνπ¥/utf-8': (
-                u'---\n'
+                '---\n'
-                u'- hétérogénéité\n'
+                '- hétérogénéité\n'
-                u'# 19.99 €\n'
+                '# 19.99 €\n'
-                u'- お早う御座います。\n'
+                '- お早う御座います。\n'
-                u'# الأَبْجَدِيَّة العَرَبِيَّة\n').encode('utf-8'),
+                '# الأَبْجَدِيَّة العَرَبِيَّة\n').encode('utf-8'),
             # dos line endings yaml
             'dos.yml': '---\r\n'
                        'dos: true',
@@ -678,6 +678,39 @@ class CommandLineTestCase(unittest.TestCase):
         self.assertEqual(
             (ctx.returncode, ctx.stdout, ctx.stderr), (1, expected_out, ''))
 
+    def test_run_list_files(self):
+        with RunContext(self) as ctx:
+            cli.run(('--list-files', self.wd))
+        self.assertEqual(ctx.returncode, 0)
+        self.assertEqual(
+            sorted(ctx.stdout.splitlines()),
+            [os.path.join(self.wd, 'a.yaml'),
+             os.path.join(self.wd, 'c.yaml'),
+             os.path.join(self.wd, 'dos.yml'),
+             os.path.join(self.wd, 'empty.yml'),
+             os.path.join(self.wd, 'en.yaml'),
+             os.path.join(self.wd, 's/s/s/s/s/s/s/s/s/s/s/s/s/s/s/file.yaml'),
+             os.path.join(self.wd, 'sub/directory.yaml/empty.yml'),
+             os.path.join(self.wd, 'sub/ok.yaml'),
+             os.path.join(self.wd, 'warn.yaml')]
+        )
+
+        config = '{ignore: "*.yml", yaml-files: ["*.*"]}'
+        with RunContext(self) as ctx:
+            cli.run(('--list-files', '-d', config, self.wd))
+        self.assertEqual(ctx.returncode, 0)
+        self.assertEqual(
+            sorted(ctx.stdout.splitlines()),
+            [os.path.join(self.wd, 'a.yaml'),
+             os.path.join(self.wd, 'c.yaml'),
+             os.path.join(self.wd, 'en.yaml'),
+             os.path.join(self.wd, 'no-yaml.json'),
+             os.path.join(self.wd, 's/s/s/s/s/s/s/s/s/s/s/s/s/s/s/file.yaml'),
+             os.path.join(self.wd, 'sub/directory.yaml/not-yaml.txt'),
+             os.path.join(self.wd, 'sub/ok.yaml'),
+             os.path.join(self.wd, 'warn.yaml')]
+        )
+
 
 class CommandLineConfigTestCase(unittest.TestCase):
     def test_config_file(self):

tests/test_config.py

@@ -22,6 +22,7 @@ import unittest
 
 from tests.common import build_temp_workspace
 
+from yamllint.config import YamlLintConfigError
 from yamllint import cli
 from yamllint import config
 
@@ -121,7 +122,7 @@ class SimpleConfigTestCase(unittest.TestCase):
         self.assertEqual(c.rules['hyphens'], False)
 
     def test_validate_rule_conf(self):
-        class Rule(object):
+        class Rule:
             ID = 'fake'
 
         self.assertFalse(config.validate_rule_conf(Rule, False))
@@ -368,7 +369,7 @@ class ExtendedConfigTestCase(unittest.TestCase):
         self.assertEqual(c.rules['colons']['max-spaces-before'], 0)
         self.assertEqual(c.rules['colons']['max-spaces-after'], 1)
 
-    def test_extended_ignore(self):
+    def test_extended_ignore_str(self):
         with tempfile.NamedTemporaryFile('w') as f:
             f.write('ignore: |\n'
                     '  *.template.yaml\n')
@@ -378,6 +379,16 @@ class ExtendedConfigTestCase(unittest.TestCase):
         self.assertEqual(c.ignore.match_file('test.template.yaml'), True)
         self.assertEqual(c.ignore.match_file('test.yaml'), False)
 
+    def test_extended_ignore_list(self):
+        with tempfile.NamedTemporaryFile('w') as f:
+            f.write('ignore:\n'
+                    '  - "*.template.yaml"\n')
+            f.flush()
+            c = config.YamlLintConfig('extends: ' + f.name + '\n')
+
+        self.assertEqual(c.ignore.match_file('test.template.yaml'), True)
+        self.assertEqual(c.ignore.match_file('test.yaml'), False)
+
 
 class ExtendedLibraryConfigTestCase(unittest.TestCase):
     def test_extend_config_disable_rule(self):
@@ -429,10 +440,10 @@ class ExtendedLibraryConfigTestCase(unittest.TestCase):
         self.assertEqual(new.rules['empty-lines']['max-end'], 0)
 
 
-class IgnorePathConfigTestCase(unittest.TestCase):
+class IgnoreConfigTestCase(unittest.TestCase):
     @classmethod
     def setUpClass(cls):
-        super(IgnorePathConfigTestCase, cls).setUpClass()
+        super().setUpClass()
 
         bad_yaml = ('---\n'
                     '- key: val1\n'
@@ -452,22 +463,6 @@ class IgnorePathConfigTestCase(unittest.TestCase):
             's/s/ign-trail/file.yaml': bad_yaml,
             's/s/ign-trail/s/s/file.yaml': bad_yaml,
             's/s/ign-trail/s/s/file2.lint-me-anyway.yaml': bad_yaml,
-
-            '.yamllint': 'ignore: |\n'
-                         '  *.dont-lint-me.yaml\n'
-                         '  /bin/\n'
-                         '  !/bin/*.lint-me-anyway.yaml\n'
-                         '\n'
-                         'extends: default\n'
-                         '\n'
-                         'rules:\n'
-                         '  key-duplicates:\n'
-                         '    ignore: |\n'
-                         '      /ign-dup\n'
-                         '  trailing-spaces:\n'
-                         '    ignore: |\n'
-                         '      ign-trail\n'
-                         '      !*.lint-me-anyway.yaml\n',
         })
 
         cls.backup_wd = os.getcwd()
@@ -475,13 +470,101 @@ class IgnorePathConfigTestCase(unittest.TestCase):
 
     @classmethod
     def tearDownClass(cls):
-        super(IgnorePathConfigTestCase, cls).tearDownClass()
+        super().tearDownClass()
 
         os.chdir(cls.backup_wd)
 
         shutil.rmtree(cls.wd)
 
-    def test_run_with_ignored_path(self):
+    def test_mutually_exclusive_ignore_keys(self):
+        self.assertRaises(
+            YamlLintConfigError,
+            config.YamlLintConfig, 'extends: default\n'
+                                   'ignore-from-file: .gitignore\n'
+                                   'ignore: |\n'
+                                   '  *.dont-lint-me.yaml\n'
+                                   '  /bin/\n')
+
+    def test_ignore_from_file_not_exist(self):
+        self.assertRaises(
+            FileNotFoundError,
+            config.YamlLintConfig, 'extends: default\n'
+                                   'ignore-from-file: not_found_file\n')
+
+    def test_ignore_from_file_incorrect_type(self):
+        self.assertRaises(
+            YamlLintConfigError,
+            config.YamlLintConfig, 'extends: default\n'
+                                   'ignore-from-file: 0\n')
+        self.assertRaises(
+            YamlLintConfigError,
+            config.YamlLintConfig, 'extends: default\n'
+                                   'ignore-from-file: [0]\n')
+
+    def test_no_ignore(self):
+        sys.stdout = StringIO()
+        with self.assertRaises(SystemExit):
+            cli.run(('-f', 'parsable', '.'))
+
+        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((
+            './bin/file.lint-me-anyway.yaml:3:3: ' + keydup,
+            './bin/file.lint-me-anyway.yaml:4:17: ' + trailing,
+            './bin/file.lint-me-anyway.yaml:5:5: ' + hyphen,
+            './bin/file.yaml:3:3: ' + keydup,
+            './bin/file.yaml:4:17: ' + trailing,
+            './bin/file.yaml:5:5: ' + hyphen,
+            './file-at-root.yaml:3:3: ' + keydup,
+            './file-at-root.yaml:4:17: ' + trailing,
+            './file-at-root.yaml:5:5: ' + hyphen,
+            './file.dont-lint-me.yaml:3:3: ' + keydup,
+            './file.dont-lint-me.yaml:4:17: ' + trailing,
+            './file.dont-lint-me.yaml:5:5: ' + hyphen,
+            './ign-dup/file.yaml:3:3: ' + keydup,
+            './ign-dup/file.yaml:4:17: ' + trailing,
+            './ign-dup/file.yaml:5:5: ' + hyphen,
+            './ign-dup/sub/dir/file.yaml:3:3: ' + keydup,
+            './ign-dup/sub/dir/file.yaml:4:17: ' + trailing,
+            './ign-dup/sub/dir/file.yaml:5:5: ' + hyphen,
+            './ign-trail/file.yaml:3:3: ' + keydup,
+            './ign-trail/file.yaml:4:17: ' + trailing,
+            './ign-trail/file.yaml:5:5: ' + hyphen,
+            './include/ign-dup/sub/dir/file.yaml:3:3: ' + keydup,
+            './include/ign-dup/sub/dir/file.yaml:4:17: ' + trailing,
+            './include/ign-dup/sub/dir/file.yaml:5:5: ' + hyphen,
+            './s/s/ign-trail/file.yaml:3:3: ' + keydup,
+            './s/s/ign-trail/file.yaml:4:17: ' + trailing,
+            './s/s/ign-trail/file.yaml:5:5: ' + hyphen,
+            './s/s/ign-trail/s/s/file.yaml:3:3: ' + keydup,
+            './s/s/ign-trail/s/s/file.yaml:4:17: ' + trailing,
+            './s/s/ign-trail/s/s/file.yaml:5:5: ' + hyphen,
+            './s/s/ign-trail/s/s/file2.lint-me-anyway.yaml:3:3: ' + keydup,
+            './s/s/ign-trail/s/s/file2.lint-me-anyway.yaml:4:17: ' + trailing,
+            './s/s/ign-trail/s/s/file2.lint-me-anyway.yaml:5:5: ' + hyphen,
+        )))
+
+    def test_run_with_ignore_str(self):
+        with open(os.path.join(self.wd, '.yamllint'), 'w') as f:
+            f.write('extends: default\n'
+                    'ignore: |\n'
+                    '  *.dont-lint-me.yaml\n'
+                    '  /bin/\n'
+                    '  !/bin/*.lint-me-anyway.yaml\n'
+                    'rules:\n'
+                    '  key-duplicates:\n'
+                    '    ignore: |\n'
+                    '      /ign-dup\n'
+                    '  trailing-spaces:\n'
+                    '    ignore: |\n'
+                    '      ign-trail\n'
+                    '      !*.lint-me-anyway.yaml\n')
+
         sys.stdout = StringIO()
         with self.assertRaises(SystemExit):
             cli.run(('-f', 'parsable', '.'))
@@ -519,3 +602,162 @@ class IgnorePathConfigTestCase(unittest.TestCase):
             './s/s/ign-trail/s/s/file2.lint-me-anyway.yaml:4:17: ' + trailing,
             './s/s/ign-trail/s/s/file2.lint-me-anyway.yaml:5:5: ' + hyphen,
         )))
+
+    def test_run_with_ignore_list(self):
+        with open(os.path.join(self.wd, '.yamllint'), 'w') as f:
+            f.write('extends: default\n'
+                    'ignore:\n'
+                    '  - "*.dont-lint-me.yaml"\n'
+                    '  - "/bin/"\n'
+                    '  - "!/bin/*.lint-me-anyway.yaml"\n'
+                    'rules:\n'
+                    '  key-duplicates:\n'
+                    '    ignore:\n'
+                    '      - "/ign-dup"\n'
+                    '  trailing-spaces:\n'
+                    '    ignore:\n'
+                    '      - "ign-trail"\n'
+                    '      - "!*.lint-me-anyway.yaml"\n')
+
+        sys.stdout = StringIO()
+        with self.assertRaises(SystemExit):
+            cli.run(('-f', 'parsable', '.'))
+
+        out = sys.stdout.getvalue()
+        out = '\n'.join(sorted(out.splitlines()))
+
+        docstart = '[warning] missing document start "---" (document-start)'
+        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((
+            './.yamllint:1:1: ' + docstart,
+            './bin/file.lint-me-anyway.yaml:3:3: ' + keydup,
+            './bin/file.lint-me-anyway.yaml:4:17: ' + trailing,
+            './bin/file.lint-me-anyway.yaml:5:5: ' + hyphen,
+            './file-at-root.yaml:3:3: ' + keydup,
+            './file-at-root.yaml:4:17: ' + trailing,
+            './file-at-root.yaml:5:5: ' + hyphen,
+            './ign-dup/file.yaml:4:17: ' + trailing,
+            './ign-dup/file.yaml:5:5: ' + hyphen,
+            './ign-dup/sub/dir/file.yaml:4:17: ' + trailing,
+            './ign-dup/sub/dir/file.yaml:5:5: ' + hyphen,
+            './ign-trail/file.yaml:3:3: ' + keydup,
+            './ign-trail/file.yaml:5:5: ' + hyphen,
+            './include/ign-dup/sub/dir/file.yaml:3:3: ' + keydup,
+            './include/ign-dup/sub/dir/file.yaml:4:17: ' + trailing,
+            './include/ign-dup/sub/dir/file.yaml:5:5: ' + hyphen,
+            './s/s/ign-trail/file.yaml:3:3: ' + keydup,
+            './s/s/ign-trail/file.yaml:5:5: ' + hyphen,
+            './s/s/ign-trail/s/s/file.yaml:3:3: ' + keydup,
+            './s/s/ign-trail/s/s/file.yaml:5:5: ' + hyphen,
+            './s/s/ign-trail/s/s/file2.lint-me-anyway.yaml:3:3: ' + keydup,
+            './s/s/ign-trail/s/s/file2.lint-me-anyway.yaml:4:17: ' + trailing,
+            './s/s/ign-trail/s/s/file2.lint-me-anyway.yaml:5:5: ' + hyphen,
+        )))
+
+    def test_run_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')
+        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')
+
+        sys.stdout = StringIO()
+        with self.assertRaises(SystemExit):
+            cli.run(('-f', 'parsable', '.'))
+
+        out = sys.stdout.getvalue()
+        out = '\n'.join(sorted(out.splitlines()))
+
+        docstart = '[warning] missing document start "---" (document-start)'
+        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((
+            './.yamllint:1:1: ' + docstart,
+            './bin/file.lint-me-anyway.yaml:3:3: ' + keydup,
+            './bin/file.lint-me-anyway.yaml:4:17: ' + trailing,
+            './bin/file.lint-me-anyway.yaml:5:5: ' + hyphen,
+            './file-at-root.yaml:3:3: ' + keydup,
+            './file-at-root.yaml:4:17: ' + trailing,
+            './file-at-root.yaml:5:5: ' + hyphen,
+            './ign-dup/file.yaml:3:3: ' + keydup,
+            './ign-dup/file.yaml:4:17: ' + trailing,
+            './ign-dup/file.yaml:5:5: ' + hyphen,
+            './ign-dup/sub/dir/file.yaml:3:3: ' + keydup,
+            './ign-dup/sub/dir/file.yaml:4:17: ' + trailing,
+            './ign-dup/sub/dir/file.yaml:5:5: ' + hyphen,
+            './ign-trail/file.yaml:3:3: ' + keydup,
+            './ign-trail/file.yaml:4:17: ' + trailing,
+            './ign-trail/file.yaml:5:5: ' + hyphen,
+            './include/ign-dup/sub/dir/file.yaml:3:3: ' + keydup,
+            './include/ign-dup/sub/dir/file.yaml:4:17: ' + trailing,
+            './include/ign-dup/sub/dir/file.yaml:5:5: ' + hyphen,
+            './s/s/ign-trail/file.yaml:3:3: ' + keydup,
+            './s/s/ign-trail/file.yaml:4:17: ' + trailing,
+            './s/s/ign-trail/file.yaml:5:5: ' + hyphen,
+            './s/s/ign-trail/s/s/file.yaml:3:3: ' + keydup,
+            './s/s/ign-trail/s/s/file.yaml:4:17: ' + trailing,
+            './s/s/ign-trail/s/s/file.yaml:5:5: ' + hyphen,
+            './s/s/ign-trail/s/s/file2.lint-me-anyway.yaml:3:3: ' + keydup,
+            './s/s/ign-trail/s/s/file2.lint-me-anyway.yaml:4:17: ' + trailing,
+            './s/s/ign-trail/s/s/file2.lint-me-anyway.yaml:5:5: ' + hyphen,
+        )))
+
+    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'
+                    'extends: default\n')
+        with open(os.path.join(self.wd, '.gitignore'), 'w') as f:
+            f.write('*.dont-lint-me.yaml\n'
+                    '/bin/\n')
+        with open(os.path.join(self.wd, '.yamlignore'), 'w') as f:
+            f.write('!/bin/*.lint-me-anyway.yaml\n')
+
+        sys.stdout = StringIO()
+        with self.assertRaises(SystemExit):
+            cli.run(('-f', 'parsable', '.'))
+
+        out = sys.stdout.getvalue()
+        out = '\n'.join(sorted(out.splitlines()))
+
+        docstart = '[warning] missing document start "---" (document-start)'
+        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((
+            './.yamllint:1:1: ' + docstart,
+            './bin/file.lint-me-anyway.yaml:3:3: ' + keydup,
+            './bin/file.lint-me-anyway.yaml:4:17: ' + trailing,
+            './bin/file.lint-me-anyway.yaml:5:5: ' + hyphen,
+            './file-at-root.yaml:3:3: ' + keydup,
+            './file-at-root.yaml:4:17: ' + trailing,
+            './file-at-root.yaml:5:5: ' + hyphen,
+            './ign-dup/file.yaml:3:3: ' + keydup,
+            './ign-dup/file.yaml:4:17: ' + trailing,
+            './ign-dup/file.yaml:5:5: ' + hyphen,
+            './ign-dup/sub/dir/file.yaml:3:3: ' + keydup,
+            './ign-dup/sub/dir/file.yaml:4:17: ' + trailing,
+            './ign-dup/sub/dir/file.yaml:5:5: ' + hyphen,
+            './ign-trail/file.yaml:3:3: ' + keydup,
+            './ign-trail/file.yaml:4:17: ' + trailing,
+            './ign-trail/file.yaml:5:5: ' + hyphen,
+            './include/ign-dup/sub/dir/file.yaml:3:3: ' + keydup,
+            './include/ign-dup/sub/dir/file.yaml:4:17: ' + trailing,
+            './include/ign-dup/sub/dir/file.yaml:5:5: ' + hyphen,
+            './s/s/ign-trail/file.yaml:3:3: ' + keydup,
+            './s/s/ign-trail/file.yaml:4:17: ' + trailing,
+            './s/s/ign-trail/file.yaml:5:5: ' + hyphen,
+            './s/s/ign-trail/s/s/file.yaml:3:3: ' + keydup,
+            './s/s/ign-trail/s/s/file.yaml:4:17: ' + trailing,
+            './s/s/ign-trail/s/s/file.yaml:5:5: ' + hyphen,
+            './s/s/ign-trail/s/s/file2.lint-me-anyway.yaml:3:3: ' + keydup,
+            './s/s/ign-trail/s/s/file2.lint-me-anyway.yaml:4:17: ' + trailing,
+            './s/s/ign-trail/s/s/file2.lint-me-anyway.yaml:5:5: ' + hyphen,
+        )))

tests/test_linter.py

@@ -31,10 +31,10 @@ class LinterTestCase(unittest.TestCase):
         linter.run(b'test: document', self.fake_config())
 
     def test_run_on_unicode(self):
-        linter.run(u'test: document', self.fake_config())
+        linter.run('test: document', self.fake_config())
 
     def test_run_on_stream(self):
-        linter.run(io.StringIO(u'hello'), self.fake_config())
+        linter.run(io.StringIO('hello'), self.fake_config())
 
     def test_run_on_int(self):
         self.assertRaises(TypeError, linter.run, 42, self.fake_config())
@@ -44,14 +44,14 @@ class LinterTestCase(unittest.TestCase):
                           ['h', 'e', 'l', 'l', 'o'], self.fake_config())
 
     def test_run_on_non_ascii_chars(self):
-        s = (u'- hétérogénéité\n'
+        s = ('- hétérogénéité\n'
-             u'# 19.99 €\n')
+             '# 19.99 €\n')
         linter.run(s, self.fake_config())
         linter.run(s.encode('utf-8'), self.fake_config())
         linter.run(s.encode('iso-8859-15'), self.fake_config())
 
-        s = (u'- お早う御座います。\n'
+        s = ('- お早う御座います。\n'
-             u'# الأَبْجَدِيَّة العَرَبِيَّة\n')
+             '# الأَبْجَدِيَّة العَرَبِيَّة\n')
         linter.run(s, self.fake_config())
         linter.run(s.encode('utf-8'), self.fake_config())
 

tests/test_spec_examples.py

@@ -13,7 +13,6 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from io import open
 import os
 
 from tests.common import RuleTestCase

yamllint/__init__.py

@@ -21,10 +21,10 @@ indentation, etc."""
 
 
 APP_NAME = 'yamllint'
-APP_VERSION = '1.27.1'
+APP_VERSION = '1.31.0'
 APP_DESCRIPTION = __doc__
 
-__author__ = u'Adrien Vergé'
+__author__ = 'Adrien Vergé'
-__copyright__ = u'Copyright 2022, Adrien Vergé'
+__copyright__ = 'Copyright 2022, Adrien Vergé'
 __license__ = 'GPLv3'
 __version__ = APP_VERSION

yamllint/cli.py

@@ -13,10 +13,7 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from __future__ import print_function
-
 import argparse
-import io
 import locale
 import os
 import platform
@@ -49,7 +46,7 @@ def supports_color():
             hasattr(sys.stdout, 'isatty') and sys.stdout.isatty())
 
 
-class Format(object):
+class Format:
     @staticmethod
     def parsable(problem, filename):
         return ('%(file)s:%(line)s:%(column)s: [%(level)s] %(message)s' %
@@ -160,6 +157,8 @@ def run(argv=None):
     config_group.add_argument('-d', '--config-data', dest='config_data',
                               action='store',
                               help='custom configuration (as YAML source)')
+    parser.add_argument('--list-files', action='store_true', dest='list_files',
+                        help='list files to lint and exit')
     parser.add_argument('-f', '--format',
                         choices=('parsable', 'standard', 'colored', 'github',
                                  'auto'),
@@ -210,14 +209,20 @@ def run(argv=None):
     if conf.locale is not None:
         locale.setlocale(locale.LC_ALL, conf.locale)
 
+    if args.list_files:
+        for file in find_files_recursively(args.files, conf):
+            if not conf.is_file_ignored(file):
+                print(file)
+        sys.exit(0)
+
     max_level = 0
 
     for file in find_files_recursively(args.files, conf):
         filepath = file[2:] if file.startswith('./') else file
         try:
-            with io.open(file, newline='') as f:
+            with open(file, newline='') as f:
                 problems = linter.run(f, conf, filepath)
-        except EnvironmentError as e:
+        except OSError as e:
             print(e, file=sys.stderr)
             sys.exit(-1)
         prob_level = show_problems(problems, file, args_format=args.format,
@@ -228,7 +233,7 @@ def run(argv=None):
     if args.stdin:
         try:
             problems = linter.run(sys.stdin, conf, '')
-        except EnvironmentError as e:
+        except OSError as e:
             print(e, file=sys.stderr)
             sys.exit(-1)
         prob_level = show_problems(problems, 'stdin', args_format=args.format,

yamllint/conf/default.yaml

@@ -6,6 +6,7 @@ yaml-files:
   - '.yamllint'
 
 rules:
+  anchors: enable
   braces: enable
   brackets: enable
   colons: enable

yamllint/config.py

@@ -13,6 +13,7 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
+import fileinput
 import os.path
 
 import pathspec
@@ -25,7 +26,7 @@ class YamlLintConfigError(Exception):
     pass
 
 
-class YamlLintConfig(object):
+class YamlLintConfig:
     def __init__(self, content=None, file=None):
         assert (content is None) ^ (file is None)
 
@@ -96,12 +97,31 @@ class YamlLintConfig(object):
             except Exception as e:
                 raise YamlLintConfigError('invalid config: %s' % e)
 
-        if 'ignore' in conf:
+        if 'ignore' in conf and 'ignore-from-file' in conf:
-            if not isinstance(conf['ignore'], str):
+            raise YamlLintConfigError(
+                'invalid config: ignore and ignore-from-file keys cannot be '
+                'used together')
+        elif 'ignore-from-file' in conf:
+            if isinstance(conf['ignore-from-file'], str):
+                conf['ignore-from-file'] = [conf['ignore-from-file']]
+            if not (isinstance(conf['ignore-from-file'], list) and all(
+                    isinstance(ln, str) for ln in conf['ignore-from-file'])):
+                raise YamlLintConfigError(
+                    'invalid config: ignore-from-file should contain '
+                    'filename(s), either as a list or string')
+            with fileinput.input(conf['ignore-from-file']) as f:
+                self.ignore = pathspec.PathSpec.from_lines('gitwildmatch', f)
+        elif 'ignore' in conf:
+            if isinstance(conf['ignore'], str):
+                self.ignore = pathspec.PathSpec.from_lines(
+                    'gitwildmatch', conf['ignore'].splitlines())
+            elif (isinstance(conf['ignore'], list) and
+                    all(isinstance(line, str) for line in conf['ignore'])):
+                self.ignore = pathspec.PathSpec.from_lines(
+                    'gitwildmatch', conf['ignore'])
+            else:
                 raise YamlLintConfigError(
                     'invalid config: ignore should contain file patterns')
-            self.ignore = pathspec.PathSpec.from_lines(
-                'gitwildmatch', conf['ignore'].splitlines())
 
         if 'yaml-files' in conf:
             if not (isinstance(conf['yaml-files'], list)
@@ -135,11 +155,16 @@ def validate_rule_conf(rule, conf):
     if isinstance(conf, dict):
         if ('ignore' in conf and
                 not isinstance(conf['ignore'], pathspec.pathspec.PathSpec)):
-            if not isinstance(conf['ignore'], str):
+            if isinstance(conf['ignore'], str):
+                conf['ignore'] = pathspec.PathSpec.from_lines(
+                    'gitwildmatch', conf['ignore'].splitlines())
+            elif (isinstance(conf['ignore'], list) and
+                    all(isinstance(line, str) for line in conf['ignore'])):
+                conf['ignore'] = pathspec.PathSpec.from_lines(
+                    'gitwildmatch', conf['ignore'])
+            else:
                 raise YamlLintConfigError(
                     'invalid config: ignore should contain file patterns')
-            conf['ignore'] = pathspec.PathSpec.from_lines(
-                'gitwildmatch', conf['ignore'].splitlines())
 
         if 'level' not in conf:
             conf['level'] = 'error'
@@ -150,7 +175,7 @@ def validate_rule_conf(rule, conf):
         options = getattr(rule, 'CONF', {})
         options_default = getattr(rule, 'DEFAULT', {})
         for optkey in conf:
-            if optkey in ('ignore', 'level'):
+            if optkey in ('ignore', 'ignore-from-file', 'level'):
                 continue
             if optkey not in options:
                 raise YamlLintConfigError(

yamllint/linter.py

@@ -14,6 +14,7 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 import re
+import io
 
 import yaml
 
@@ -29,8 +30,11 @@ PROBLEM_LEVELS = {
     'error': 2,
 }
 
+DISABLE_RULE_PATTERN = re.compile(r'^# yamllint disable( rule:\S+)*\s*$')
+ENABLE_RULE_PATTERN = re.compile(r'^# yamllint enable( rule:\S+)*\s*$')
 
-class LintProblem(object):
+
+class LintProblem:
     """Represents a linting problem found by yamllint."""
     def __init__(self, line, column, desc='<no description>', rule=None):
         #: Line on which the problem was found (starting at 1)
@@ -82,7 +86,7 @@ def get_cosmetic_problems(buffer, conf, filepath):
         def process_comment(self, comment):
             comment = str(comment)
 
-            if re.match(r'^# yamllint disable( rule:\S+)*\s*$', comment):
+            if DISABLE_RULE_PATTERN.match(comment):
                 items = comment[18:].rstrip().split(' ')
                 rules = [item[5:] for item in items][1:]
                 if len(rules) == 0:
@@ -92,7 +96,7 @@ def get_cosmetic_problems(buffer, conf, filepath):
                         if id in self.all_rules:
                             self.rules.add(id)
 
-            elif re.match(r'^# yamllint enable( rule:\S+)*\s*$', comment):
+            elif ENABLE_RULE_PATTERN.match(comment):
                 items = comment[17:].rstrip().split(' ')
                 rules = [item[5:] for item in items][1:]
                 if len(rules) == 0:
@@ -118,7 +122,7 @@ def get_cosmetic_problems(buffer, conf, filepath):
                         if id in self.all_rules:
                             self.rules.add(id)
 
-    # Use a cache to store problems and flush it only when a end of line is
+    # Use a cache to store problems and flush it only when an end of line is
     # found. This allows the use of yamllint directive to disable some rules on
     # some lines.
     cache = []
@@ -219,12 +223,12 @@ def run(input, conf, filepath=None):
     :param input: buffer, string or stream to read from
     :param conf: yamllint configuration object
     """
-    if conf.is_file_ignored(filepath):
+    if filepath is not None and conf.is_file_ignored(filepath):
         return ()
 
     if isinstance(input, (bytes, str)):
         return _run(input, conf, filepath)
-    elif hasattr(input, 'read'):  # Python 2's file or Python 3's io.IOBase
+    elif isinstance(input, io.IOBase):
         # We need to have everything in memory to parse correctly
         content = input.read()
         return _run(content, conf, filepath)

yamllint/parser.py

@@ -16,7 +16,7 @@
 import yaml
 
 
-class Line(object):
+class Line:
     def __init__(self, line_no, buffer, start, end):
         self.line_no = line_no
         self.start = start
@@ -28,7 +28,7 @@ class Line(object):
         return self.buffer[self.start:self.end]
 
 
-class Token(object):
+class Token:
     def __init__(self, line_no, curr, prev, next, nextnext):
         self.line_no = line_no
         self.curr = curr
@@ -37,7 +37,7 @@ class Token(object):
         self.nextnext = nextnext
 
 
-class Comment(object):
+class Comment:
     def __init__(self, line_no, column_no, buffer, pointer,
                  token_before=None, token_after=None, comment_before=None):
         self.line_no = line_no
@@ -132,8 +132,7 @@ def token_or_comment_generator(buffer):
 
             yield Token(curr.start_mark.line + 1, curr, prev, next, nextnext)
 
-            for comment in comments_between_tokens(curr, next):
+            yield from comments_between_tokens(curr, next)
-                yield comment
 
             prev = curr
             curr = next

yamllint/rules/__init__.py

@@ -14,6 +14,7 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 from yamllint.rules import (
+    anchors,
     braces,
     brackets,
     colons,
@@ -39,6 +40,7 @@ from yamllint.rules import (
 )
 
 _RULES = {
+    anchors.ID: anchors,
     braces.ID: braces,
     brackets.ID: brackets,
     colons.ID: colons,

yamllint/rules/anchors.py

@@ -0,0 +1,118 @@
+# Copyright (C) 2023 Adrien Vergé
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+"""
+Use this rule to report duplicated anchors and aliases referencing undeclared
+anchors.
+
+.. rubric:: Options
+
+* Set ``forbid-undeclared-aliases`` to ``true`` to avoid aliases that reference
+  an anchor that hasn't been declared (either not declared at all, or declared
+  later in the document).
+* Set ``forbid-duplicated-anchors`` to ``true`` to avoid duplications of a same
+  anchor.
+
+.. rubric:: Default values (when enabled)
+
+.. code-block:: yaml
+
+ rules:
+   anchors:
+     forbid-undeclared-aliases: true
+     forbid-duplicated-anchors: false
+
+.. rubric:: Examples
+
+#. With ``anchors: {forbid-undeclared-aliases: true}``
+
+   the following code snippet would **PASS**:
+   ::
+
+    ---
+    - &anchor
+      foo: bar
+    - *anchor
+
+   the following code snippet would **FAIL**:
+   ::
+
+    ---
+    - &anchor
+      foo: bar
+    - *unknown
+
+   the following code snippet would **FAIL**:
+   ::
+
+    ---
+    - &anchor
+      foo: bar
+    - <<: *unknown
+      extra: value
+
+#. With ``anchors: {forbid-duplicated-anchors: true}``
+
+   the following code snippet would **PASS**:
+   ::
+
+    ---
+    - &anchor1 Foo Bar
+    - &anchor2 [item 1, item 2]
+
+   the following code snippet would **FAIL**:
+   ::
+
+    ---
+    - &anchor Foo Bar
+    - &anchor [item 1, item 2]
+"""
+
+
+import yaml
+
+from yamllint.linter import LintProblem
+
+
+ID = 'anchors'
+TYPE = 'token'
+CONF = {'forbid-undeclared-aliases': bool,
+        'forbid-duplicated-anchors': bool}
+DEFAULT = {'forbid-undeclared-aliases': True,
+           'forbid-duplicated-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'] and
+            isinstance(token, yaml.AliasToken) and
+            token.value not in context['anchors']):
+        yield LintProblem(
+            token.start_mark.line + 1, token.start_mark.column + 1,
+            f'found undeclared alias "{token.value}"')
+
+    if (conf['forbid-duplicated-anchors'] and
+            isinstance(token, yaml.AnchorToken) and
+            token.value in context['anchors']):
+        yield LintProblem(
+            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 isinstance(token, yaml.AnchorToken):
+            context['anchors'].add(token.value)

yamllint/rules/colons.py

@@ -92,7 +92,9 @@ DEFAULT = {'max-spaces-before': 0,
 
 
 def check(conf, token, prev, next, nextnext, context):
-    if isinstance(token, yaml.ValueToken):
+    if isinstance(token, yaml.ValueToken) and not (
+            isinstance(prev, yaml.AliasToken) and
+            token.start_mark.pointer - prev.end_mark.pointer == 1):
         problem = spaces_before(token, prev, next,
                                 max=conf['max-spaces-before'],
                                 max_desc='too many spaces before colon')

yamllint/rules/comments_indentation.py

@@ -117,8 +117,7 @@ def check(conf, comment):
     #         # comment
     #         - 1
     #         - 2
-    if prev_line_indent <= next_line_indent:
+    prev_line_indent = max(prev_line_indent, next_line_indent)
-        prev_line_indent = next_line_indent
 
     # If two indents are valid but a previous comment went back to normal
     # indent, for the next ones to do the same. In other words, avoid this:

yamllint/rules/float_values.py

@@ -107,13 +107,13 @@ DEFAULT = {
 }
 
 IS_NUMERAL_BEFORE_DECIMAL_PATTERN = (
-    re.compile('[-+]?(\\.[0-9]+)([eE][-+]?[0-9]+)?')
+    re.compile('[-+]?(\\.[0-9]+)([eE][-+]?[0-9]+)?$')
 )
 IS_SCIENTIFIC_NOTATION_PATTERN = re.compile(
-    '[-+]?(\\.[0-9]+|[0-9]+(\\.[0-9]*)?)([eE][-+]?[0-9]+)'
+    '[-+]?(\\.[0-9]+|[0-9]+(\\.[0-9]*)?)([eE][-+]?[0-9]+)$'
 )
-IS_INF_PATTERN = re.compile('[-+]?(\\.inf|\\.Inf|\\.INF)')
+IS_INF_PATTERN = re.compile('[-+]?(\\.inf|\\.Inf|\\.INF)$')
-IS_NAN_PATTERN = re.compile('\\.nan|\\.NaN|\\.NAN')
+IS_NAN_PATTERN = re.compile('(\\.nan|\\.NaN|\\.NAN)$')
 
 
 def check(conf, token, prev, next, nextnext, context):

yamllint/rules/indentation.py

@@ -218,7 +218,7 @@ ROOT, B_MAP, F_MAP, B_SEQ, F_SEQ, B_ENT, KEY, VAL = range(8)
 labels = ('ROOT', 'B_MAP', 'F_MAP', 'B_SEQ', 'F_SEQ', 'B_ENT', 'KEY', 'VAL')
 
 
-class Parent(object):
+class Parent:
     def __init__(self, type, indent, line_indent=None):
         self.type = type
         self.indent = indent
@@ -341,14 +341,18 @@ def _check(conf, token, prev, next, nextnext, context):
             expected = detect_indent(expected, token)
 
         if found_indentation != expected:
-            yield LintProblem(token.start_mark.line + 1, found_indentation + 1,
+            if expected < 0:
-                              'wrong indentation: expected %d but found %d' %
+                message = 'wrong indentation: expected at least %d' % \
-                              (expected, found_indentation))
+                          (found_indentation + 1)
+            else:
+                message = 'wrong indentation: expected %d but found %d' % \
+                          (expected, found_indentation)
+            yield LintProblem(token.start_mark.line + 1,
+                              found_indentation + 1, message)
 
     if (isinstance(token, yaml.ScalarToken) and
             conf['check-multi-line-strings']):
-        for problem in check_scalar_indentation(conf, token, context):
+        yield from check_scalar_indentation(conf, token, context)
-            yield problem
 
     # Step 2.a:
 
@@ -493,8 +497,8 @@ def _check(conf, token, prev, next, nextnext, context):
                         # indentation it should have (because `spaces` is
                         # `consistent` and its value has not been computed yet
                         # -- this is probably the beginning of the document).
-                        # So we choose an arbitrary value (2).
+                        # So we choose an unknown value (-1).
-                        indent = 2
+                        indent = -1
                     else:
                         indent = detect_indent(context['stack'][-1].indent,
                                                next)
@@ -576,8 +580,7 @@ def _check(conf, token, prev, next, nextnext, context):
 
 def check(conf, token, prev, next, nextnext, context):
     try:
-        for problem in _check(conf, token, prev, next, nextnext, context):
+        yield from _check(conf, token, prev, next, nextnext, context)
-            yield problem
     except AssertionError:
         yield LintProblem(token.start_mark.line + 1,
                           token.start_mark.column + 1,

yamllint/rules/key_duplicates.py

@@ -64,7 +64,7 @@ TYPE = 'token'
 MAP, SEQ = range(2)
 
 
-class Parent(object):
+class Parent:
     def __init__(self, type):
         self.type = type
         self.keys = []

yamllint/rules/key_ordering.py

@@ -93,7 +93,7 @@ TYPE = 'token'
 MAP, SEQ = range(2)
 
 
-class Parent(object):
+class Parent:
     def __init__(self, type):
         self.type = type
         self.keys = []

yamllint/rules/new_line_at_end_of_file.py

@@ -17,7 +17,7 @@
 Use this rule to require a new line character (``\\n``) at the end of files.
 
 The POSIX standard `requires the last line to end with a new line character
-<http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap03.html#tag_03_206>`_.
+<https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap03.html#tag_03_206>`_.
 All UNIX tools expect a new line at the end of files. Most text editors use
 this convention too.
 """

yamllint/rules/octal_values.py

@@ -96,7 +96,7 @@ def check(conf, token, prev, next, nextnext, context):
             if not token.style:
                 val = token.value
                 if (val.isdigit() and len(val) > 1 and val[0] == '0' and
-                        IS_OCTAL_NUMBER_PATTERN.match(val[1:]) is not None):
+                        IS_OCTAL_NUMBER_PATTERN.match(val[1:])):
                     yield LintProblem(
                         token.start_mark.line + 1, token.end_mark.column + 1,
                         'forbidden implicit octal value "%s"' %
@@ -107,7 +107,7 @@ def check(conf, token, prev, next, nextnext, context):
             if not token.style:
                 val = token.value
                 if (len(val) > 2 and val[:2] == '0o' and
-                        IS_OCTAL_NUMBER_PATTERN.match(val[2:]) is not None):
+                        IS_OCTAL_NUMBER_PATTERN.match(val[2:])):
                     yield LintProblem(
                         token.start_mark.line + 1, token.end_mark.column + 1,
                         'forbidden explicit octal value "%s"' %

yamllint/rules/quoted_strings.py

@@ -30,6 +30,8 @@ used.
   ``required: false`` and  ``required: only-when-needed``.
 * ``extra-allowed`` is a list of PCRE regexes to allow quoted string values,
   even if ``required: only-when-needed`` is set.
+* ``allow-quoted-quotes`` allows (``true``) using disallowed quotes for strings
+  with allowed quotes inside. Default ``false``.
 
 **Note**: Multi-line strings (with ``|`` or ``>``) will not be checked.
 
@@ -43,6 +45,7 @@ used.
      required: true
      extra-required: []
      extra-allowed: []
+     allow-quoted-quotes: false
 
 .. rubric:: Examples
 
@@ -112,6 +115,26 @@ used.
 
     - "localhost"
     - this is a string that needs to be QUOTED
+
+#. With ``quoted-strings: {quote-type: double, allow-quoted-quotes: false}``
+
+   the following code snippet would **PASS**:
+   ::
+
+    foo: "bar\\"baz"
+
+   the following code snippet would **FAIL**:
+   ::
+
+    foo: 'bar"baz'
+
+#. With ``quoted-strings: {quote-type: double, allow-quoted-quotes: true}``
+
+   the following code snippet would **PASS**:
+   ::
+
+    foo: 'bar"baz'
+
 """
 
 import re
@@ -125,11 +148,13 @@ TYPE = 'token'
 CONF = {'quote-type': ('any', 'single', 'double'),
         'required': (True, False, 'only-when-needed'),
         'extra-required': [str],
-        'extra-allowed': [str]}
+        'extra-allowed': [str],
+        'allow-quoted-quotes': bool}
 DEFAULT = {'quote-type': 'any',
            'required': True,
            'extra-required': [],
-           'extra-allowed': []}
+           'extra-allowed': [],
+           'allow-quoted-quotes': False}
 
 
 def VALIDATE(conf):
@@ -141,7 +166,7 @@ def VALIDATE(conf):
         return 'cannot use both "required: false" and "extra-allowed"'
 
 
-DEFAULT_SCALAR_TAG = u'tag:yaml.org,2002:str'
+DEFAULT_SCALAR_TAG = 'tag:yaml.org,2002:str'
 
 # https://stackoverflow.com/a/36514274
 yaml.resolver.Resolver.add_implicit_resolver(
@@ -177,6 +202,12 @@ def _quotes_are_needed(string):
         return True
 
 
+def _has_quoted_quotes(token):
+    return ((not token.plain) and
+            ((token.style == "'" and '"' in token.value) or
+             (token.style == '"' and "'" in token.value)))
+
+
 def check(conf, token, prev, next, nextnext, context):
     if not (isinstance(token, yaml.tokens.ScalarToken) and
             isinstance(prev, (yaml.BlockEntryToken, yaml.FlowEntryToken,
@@ -197,7 +228,7 @@ def check(conf, token, prev, next, nextnext, context):
         return
 
     # Ignore multi-line strings
-    if (not token.plain) and (token.style == "|" or token.style == ">"):
+    if not token.plain and token.style in ("|", ">"):
         return
 
     quote_type = conf['quote-type']
@@ -206,13 +237,18 @@ def check(conf, token, prev, next, nextnext, context):
     if conf['required'] is True:
 
         # Quotes are mandatory and need to match config
-        if token.style is None or not _quote_match(quote_type, token.style):
+        if (token.style is None or
+            not (_quote_match(quote_type, token.style) or
+                 (conf['allow-quoted-quotes'] and _has_quoted_quotes(token)))):
             msg = "string value is not quoted with %s quotes" % quote_type
 
     elif conf['required'] is False:
 
         # Quotes are not mandatory but when used need to match config
-        if token.style and not _quote_match(quote_type, token.style):
+        if (token.style and
+                not _quote_match(quote_type, token.style) and
+                not (conf['allow-quoted-quotes'] and
+                     _has_quoted_quotes(token))):
             msg = "string value is not quoted with %s quotes" % quote_type
 
         elif not token.style:
@@ -235,7 +271,9 @@ def check(conf, token, prev, next, nextnext, context):
                     quote_type)
 
         # But when used need to match config
-        elif token.style and not _quote_match(quote_type, token.style):
+        elif (token.style and
+              not _quote_match(quote_type, token.style) and
+              not (conf['allow-quoted-quotes'] and _has_quoted_quotes(token))):
             msg = "string value is not quoted with %s quotes" % quote_type
 
         elif not token.style:

yamllint/rules/truthy.py

@@ -14,7 +14,7 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 """
-Use this rule to forbid non-explictly typed truthy values other than allowed
+Use this rule to forbid non-explicitly typed truthy values other than allowed
 ones (by default: ``true`` and ``false``), for example ``YES`` or ``off``.
 
 This can be useful to prevent surprises from YAML parsers transforming