yamllint version 1.11.0

See issue https://github.com/PyCQA/flake8-import-order/issues/149

.travis.yml

@@ -9,12 +9,18 @@ python:
   - 3.6
   - nightly
 install:
-  - pip install pyyaml flake8 flake8-import-order coveralls
+  - pip install pyyaml flake8 flake8-import-order coveralls sphinx
   - if [[ $TRAVIS_PYTHON_VERSION == 2.6 ]]; then pip install unittest2; fi
   - pip install .
 script:
   - if [[ $TRAVIS_PYTHON_VERSION != 2.6 ]]; then flake8 .; fi
+  # Because of https://github.com/PyCQA/flake8-import-order/issues/149
+  # otherwise tests fail with Python 3.6:
+  - pip uninstall --yes enum34
   - yamllint --strict $(git ls-files '*.yaml' '*.yml')
   - coverage run --source=yamllint setup.py test
+  - if [[ $TRAVIS_PYTHON_VERSION != 2* ]]; then
+      python setup.py build_sphinx;
+    fi
 after_success:
   coveralls

CHANGELOG.rst

@@ -1,6 +1,21 @@
 Changelog
 =========
 
+1.11.0 (2018-02-21)
+-------------------
+
+- Add a new `octal-values` rule
+
+1.10.0 (2017-11-05)
+-------------------
+
+- Fix colored output on Windows
+- Check documentation compilation on continuous integration
+- Add a new `empty-values` rule
+- Make sure test files are included in dist bundle
+- Tests: Use en_US.UTF-8 locale when C.UTF-8 not available
+- Tests: Dynamically detect Python executable path
+
 1.9.0 (2017-10-16)
 ------------------
 

MANIFEST.in

@@ -1,3 +1,4 @@
 include LICENSE
 include README.rst
 include docs/*
+include tests/*.py tests/rules/*.py tests/yaml-1.2-spec-examples/*

docs/rules.rst

@@ -59,6 +59,11 @@ empty-lines
 
 .. automodule:: yamllint.rules.empty_lines
 
+empty-values
+------------
+
+.. automodule:: yamllint.rules.empty_values
+
 hyphens
 -------
 
@@ -94,6 +99,11 @@ new-lines
 
 .. automodule:: yamllint.rules.new_lines
 
+octal-values
+------------
+
+.. automodule:: yamllint.rules.octal_values
+
 trailing-spaces
 ---------------
 

setup.cfg

@@ -3,3 +3,10 @@ universal = 1
 
 [flake8]
 import-order-style = pep8
+application-import-names = yamllint
+
+[build_sphinx]
+all-files = 1
+source-dir = docs
+build-dir = docs/_build
+warning-is-error = 1

setup.py

@@ -44,8 +44,7 @@ setup(
 
     packages=find_packages(exclude=['tests', 'tests.*']),
     entry_points={'console_scripts': ['yamllint=yamllint.cli:run']},
-    package_data={'yamllint': ['conf/*.yaml'],
-                  'tests': ['yaml-1.2-spec-examples/*']},
+    package_data={'yamllint': ['conf/*.yaml']},
     install_requires=['pathspec >=0.5.3', 'pyyaml'],
     test_suite='tests',
 )

tests/common.py

@@ -20,7 +20,7 @@ import sys
 try:
     assert sys.version_info >= (2, 7)
     import unittest
-except:
+except AssertionError:
     import unittest2 as unittest
 
 import yaml

tests/rules/test_empty_values.py

@@ -0,0 +1,261 @@
+# -*- coding: utf-8 -*-
+# Copyright (C) 2017 Greg Dubicki
+#
+# 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 EmptyValuesTestCase(RuleTestCase):
+    rule_id = 'empty-values'
+
+    def test_disabled(self):
+        conf = ('empty-values: disable\n'
+                'braces: disable\n'
+                'commas: disable\n')
+        self.check('---\n'
+                   'foo:\n', conf)
+        self.check('---\n'
+                   'foo:\n'
+                   ' bar:\n', conf)
+        self.check('---\n'
+                   '{a:}\n', conf)
+        self.check('---\n'
+                   'foo: {a:}\n', conf)
+        self.check('---\n'
+                   '- {a:}\n'
+                   '- {a:, b: 2}\n'
+                   '- {a: 1, b:}\n'
+                   '- {a: 1, b: , }\n', conf)
+        self.check('---\n'
+                   '{a: {b: , c: {d: 4, e:}}, f:}\n', conf)
+
+    def test_in_block_mappings_disabled(self):
+        conf = ('empty-values: {forbid-in-block-mappings: false,\n'
+                '               forbid-in-flow-mappings: false}\n')
+        self.check('---\n'
+                   'foo:\n', conf)
+        self.check('---\n'
+                   'foo:\n'
+                   'bar: aaa\n', conf)
+
+    def test_in_block_mappings_single_line(self):
+        conf = ('empty-values: {forbid-in-block-mappings: true,\n'
+                '               forbid-in-flow-mappings: false}\n')
+        self.check('---\n'
+                   'implicitly-null:\n', conf, problem1=(2, 17))
+        self.check('---\n'
+                   'implicitly-null:with-colons:in-key:\n', conf,
+                   problem1=(2, 36))
+        self.check('---\n'
+                   'implicitly-null:with-colons:in-key2:\n', conf,
+                   problem1=(2, 37))
+
+    def test_in_block_mappings_all_lines(self):
+        conf = ('empty-values: {forbid-in-block-mappings: true,\n'
+                '               forbid-in-flow-mappings: false}\n')
+        self.check('---\n'
+                   'foo:\n'
+                   'bar:\n'
+                   'foobar:\n', conf, problem1=(2, 5),
+                   problem2=(3, 5), problem3=(4, 8))
+
+    def test_in_block_mappings_explicit_end_of_document(self):
+        conf = ('empty-values: {forbid-in-block-mappings: true,\n'
+                '               forbid-in-flow-mappings: false}\n')
+        self.check('---\n'
+                   'foo:\n'
+                   '...\n', conf, problem1=(2, 5))
+
+    def test_in_block_mappings_not_end_of_document(self):
+        conf = ('empty-values: {forbid-in-block-mappings: true,\n'
+                '               forbid-in-flow-mappings: false}\n')
+        self.check('---\n'
+                   'foo:\n'
+                   'bar:\n'
+                   ' aaa\n', conf, problem1=(2, 5))
+
+    def test_in_block_mappings_different_level(self):
+        conf = ('empty-values: {forbid-in-block-mappings: true,\n'
+                '               forbid-in-flow-mappings: false}\n')
+        self.check('---\n'
+                   'foo:\n'
+                   ' bar:\n'
+                   'aaa: bbb\n', conf, problem1=(3, 6))
+
+    def test_in_block_mappings_empty_flow_mapping(self):
+        conf = ('empty-values: {forbid-in-block-mappings: true,\n'
+                '               forbid-in-flow-mappings: false}\n'
+                'braces: disable\n'
+                'commas: disable\n')
+        self.check('---\n'
+                   'foo: {a:}\n', conf)
+        self.check('---\n'
+                   '- {a:, b: 2}\n'
+                   '- {a: 1, b:}\n'
+                   '- {a: 1, b: , }\n', conf)
+
+    def test_in_block_mappings_empty_block_sequence(self):
+        conf = ('empty-values: {forbid-in-block-mappings: true,\n'
+                '               forbid-in-flow-mappings: false}\n')
+        self.check('---\n'
+                   'foo:\n'
+                   '  -\n', conf)
+
+    def test_in_block_mappings_not_empty_or_explicit_null(self):
+        conf = ('empty-values: {forbid-in-block-mappings: true,\n'
+                '               forbid-in-flow-mappings: false}\n')
+        self.check('---\n'
+                   'foo:\n'
+                   ' bar:\n'
+                   '  aaa\n', conf)
+        self.check('---\n'
+                   'explicitly-null: null\n', conf)
+        self.check('---\n'
+                   'explicitly-null:with-colons:in-key: null\n', conf)
+        self.check('---\n'
+                   'false-null: nulL\n', conf)
+        self.check('---\n'
+                   'empty-string: \'\'\n', conf)
+        self.check('---\n'
+                   'nullable-boolean: false\n', conf)
+        self.check('---\n'
+                   'nullable-int: 0\n', conf)
+        self.check('---\n'
+                   'First occurrence: &anchor Foo\n'
+                   'Second occurrence: *anchor\n', conf)
+
+    def test_in_block_mappings_various_explicit_null(self):
+        conf = ('empty-values: {forbid-in-block-mappings: true,\n'
+                '               forbid-in-flow-mappings: false}\n')
+        self.check('---\n'
+                   'null-alias: ~\n', conf)
+        self.check('---\n'
+                   'null-key1: {?: val}\n', conf)
+        self.check('---\n'
+                   'null-key2: {? !!null "": val}\n', conf)
+
+    def test_in_block_mappings_comments(self):
+        conf = ('empty-values: {forbid-in-block-mappings: true,\n'
+                '               forbid-in-flow-mappings: false}\n'
+                'comments: disable\n')
+        self.check('---\n'
+                   'empty:  # comment\n'
+                   'foo:\n'
+                   '  bar: # comment\n', conf,
+                   problem1=(2, 7),
+                   problem2=(4, 7))
+
+    def test_in_flow_mappings_disabled(self):
+        conf = ('empty-values: {forbid-in-block-mappings: false,\n'
+                '               forbid-in-flow-mappings: false}\n'
+                'braces: disable\n'
+                'commas: disable\n')
+        self.check('---\n'
+                   '{a:}\n', conf)
+        self.check('---\n'
+                   'foo: {a:}\n', conf)
+        self.check('---\n'
+                   '- {a:}\n'
+                   '- {a:, b: 2}\n'
+                   '- {a: 1, b:}\n'
+                   '- {a: 1, b: , }\n', conf)
+        self.check('---\n'
+                   '{a: {b: , c: {d: 4, e:}}, f:}\n', conf)
+
+    def test_in_flow_mappings_single_line(self):
+        conf = ('empty-values: {forbid-in-block-mappings: false,\n'
+                '               forbid-in-flow-mappings: true}\n'
+                'braces: disable\n'
+                'commas: disable\n')
+        self.check('---\n'
+                   '{a:}\n', conf,
+                   problem=(2, 4))
+        self.check('---\n'
+                   'foo: {a:}\n', conf,
+                   problem=(2, 9))
+        self.check('---\n'
+                   '- {a:}\n'
+                   '- {a:, b: 2}\n'
+                   '- {a: 1, b:}\n'
+                   '- {a: 1, b: , }\n', conf,
+                   problem1=(2, 6),
+                   problem2=(3, 6),
+                   problem3=(4, 12),
+                   problem4=(5, 12))
+        self.check('---\n'
+                   '{a: {b: , c: {d: 4, e:}}, f:}\n', conf,
+                   problem1=(2, 8),
+                   problem2=(2, 23),
+                   problem3=(2, 29))
+
+    def test_in_flow_mappings_multi_line(self):
+        conf = ('empty-values: {forbid-in-block-mappings: false,\n'
+                '               forbid-in-flow-mappings: true}\n'
+                'braces: disable\n'
+                'commas: disable\n')
+        self.check('---\n'
+                   'foo: {\n'
+                   '  a:\n'
+                   '}\n', conf,
+                   problem=(3, 5))
+        self.check('---\n'
+                   '{\n'
+                   '  a: {\n'
+                   '    b: ,\n'
+                   '    c: {\n'
+                   '      d: 4,\n'
+                   '      e:\n'
+                   '    }\n'
+                   '  },\n'
+                   '  f:\n'
+                   '}\n', conf,
+                   problem1=(4, 7),
+                   problem2=(7, 9),
+                   problem3=(10, 5))
+
+    def test_in_flow_mappings_various_explicit_null(self):
+        conf = ('empty-values: {forbid-in-block-mappings: false,\n'
+                '               forbid-in-flow-mappings: true}\n'
+                'braces: disable\n'
+                'commas: disable\n')
+        self.check('---\n'
+                   '{explicit-null: null}\n', conf)
+        self.check('---\n'
+                   '{null-alias: ~}\n', conf)
+        self.check('---\n'
+                   'null-key1: {?: val}\n', conf)
+        self.check('---\n'
+                   'null-key2: {? !!null "": val}\n', conf)
+
+    def test_in_flow_mappings_comments(self):
+        conf = ('empty-values: {forbid-in-block-mappings: false,\n'
+                '               forbid-in-flow-mappings: true}\n'
+                'braces: disable\n'
+                'commas: disable\n'
+                'comments: disable\n')
+        self.check('---\n'
+                   '{\n'
+                   '  a: {\n'
+                   '    b: ,  # comment\n'
+                   '    c: {\n'
+                   '      d: 4,  # comment\n'
+                   '      e:  # comment\n'
+                   '    }\n'
+                   '  },\n'
+                   '  f:  # comment\n'
+                   '}\n', conf,
+                   problem1=(4, 7),
+                   problem2=(7, 9),
+                   problem3=(10, 5))

tests/rules/test_indentation.py

@@ -15,6 +15,7 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 from tests.common import RuleTestCase
+
 from yamllint.parser import token_or_comment_generator, Comment
 from yamllint.rules.indentation import check
 

tests/rules/test_octal_values.py

@@ -0,0 +1,72 @@
+# -*- coding: utf-8 -*-
+# Copyright (C) 2016 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 OctalValuesTestCase(RuleTestCase):
+    rule_id = 'octal-values'
+
+    def test_disabled(self):
+        conf = ('octal-values: disable\n'
+                'new-line-at-end-of-file: disable\n'
+                'document-start: disable\n')
+        self.check('user-city: 010', conf)
+        self.check('user-city: 0o10', conf)
+
+    def test_implicit_octal_values(self):
+        conf = ('octal-values: {forbid-implicit-octal: true}\n'
+                'new-line-at-end-of-file: disable\n'
+                'document-start: disable\n')
+        self.check('user-city: 010', conf, problem=(1, 15))
+        self.check('user-city: abc', conf)
+        self.check('user-city: 010,0571', conf)
+        self.check("user-city: '010'", conf)
+        self.check('user-city: "010"', conf)
+        self.check('user-city:\n'
+                   '  - 010', conf, problem=(2, 8))
+        self.check('user-city: [010]', conf, problem=(1, 16))
+        self.check('user-city: {beijing: 010}', conf, problem=(1, 25))
+        self.check('explicit-octal: 0o10', conf)
+        self.check('not-number: 0abc', conf)
+        self.check('zero: 0', conf)
+        self.check('hex-value: 0x10', conf)
+        self.check('number-values:\n'
+                   '  - 0.10\n'
+                   '  - .01\n'
+                   '  - 0e3\n', conf)
+
+    def test_explicit_octal_values(self):
+        conf = ('octal-values: {forbid-explicit-octal: true}\n'
+                'new-line-at-end-of-file: disable\n'
+                'document-start: disable\n')
+        self.check('user-city: 0o10', conf, problem=(1, 16))
+        self.check('user-city: abc', conf)
+        self.check('user-city: 0o10,0571', conf)
+        self.check("user-city: '0o10'", conf)
+        self.check('user-city:\n'
+                   '  - 0o10', conf, problem=(2, 9))
+        self.check('user-city: [0o10]', conf, problem=(1, 17))
+        self.check('user-city: {beijing: 0o10}', conf, problem=(1, 26))
+        self.check('implicit-octal: 010', conf)
+        self.check('not-number: 0oabc', conf)
+        self.check('zero: 0', conf)
+        self.check('hex-value: 0x10', conf)
+        self.check('number-values:\n'
+                   '  - 0.10\n'
+                   '  - .01\n'
+                   '  - 0e3\n', conf)
+        self.check('user-city: "010"', conf)

tests/test_cli.py

@@ -27,13 +27,13 @@ import sys
 try:
     assert sys.version_info >= (2, 7)
     import unittest
-except:
+except AssertionError:
     import unittest2 as unittest
 
-from yamllint import cli
-
 from tests.common import build_temp_workspace
 
+from yamllint import cli
+
 
 @unittest.skipIf(sys.version_info < (2, 7), 'Python 2.6 not supported')
 class CommandLineTestCase(unittest.TestCase):
@@ -299,7 +299,10 @@ class CommandLineTestCase(unittest.TestCase):
         # Make sure the default localization conditions on this "system"
         # support UTF-8 encoding.
         loc = locale.getlocale()
-        locale.setlocale(locale.LC_ALL, 'C.UTF-8')
+        try:
+            locale.setlocale(locale.LC_ALL, 'C.UTF-8')
+        except locale.Error:
+            locale.setlocale(locale.LC_ALL, 'en_US.UTF-8')
 
         sys.stdout, sys.stderr = StringIO(), StringIO()
         with self.assertRaises(SystemExit) as ctx:

tests/test_config.py

@@ -24,14 +24,14 @@ import sys
 try:
     assert sys.version_info >= (2, 7)
     import unittest
-except:
+except AssertionError:
     import unittest2 as unittest
 
+from tests.common import build_temp_workspace
+
 from yamllint import cli
 from yamllint import config
 
-from tests.common import build_temp_workspace
-
 
 class SimpleConfigTestCase(unittest.TestCase):
     def test_parse_config(self):

tests/test_linter.py

@@ -19,7 +19,7 @@ import sys
 try:
     assert sys.version_info >= (2, 7)
     import unittest
-except:
+except AssertionError:
     import unittest2 as unittest
 
 from yamllint.config import YamlLintConfig

tests/test_module.py

@@ -22,10 +22,13 @@ import sys
 try:
     assert sys.version_info >= (2, 7)
     import unittest
-except:
+except AssertionError:
     import unittest2 as unittest
 
 
+PYTHON = sys.executable or 'python'
+
+
 @unittest.skipIf(sys.version_info < (2, 7), 'Python 2.6 not supported')
 class ModuleTestCase(unittest.TestCase):
     def setUp(self):
@@ -46,7 +49,7 @@ class ModuleTestCase(unittest.TestCase):
 
     def test_run_module_no_args(self):
         with self.assertRaises(subprocess.CalledProcessError) as ctx:
-            subprocess.check_output(['python', '-m', 'yamllint'],
+            subprocess.check_output([PYTHON, '-m', 'yamllint'],
                                     stderr=subprocess.STDOUT)
         self.assertEqual(ctx.exception.returncode, 2)
         self.assertRegexpMatches(ctx.exception.output.decode(),
@@ -54,7 +57,7 @@ class ModuleTestCase(unittest.TestCase):
 
     def test_run_module_on_bad_dir(self):
         with self.assertRaises(subprocess.CalledProcessError) as ctx:
-            subprocess.check_output(['python', '-m', 'yamllint',
+            subprocess.check_output([PYTHON, '-m', 'yamllint',
                                      '/does/not/exist'],
                                     stderr=subprocess.STDOUT)
         self.assertRegexpMatches(ctx.exception.output.decode(),
@@ -62,7 +65,7 @@ class ModuleTestCase(unittest.TestCase):
 
     def test_run_module_on_file(self):
         out = subprocess.check_output(
-            ['python', '-m', 'yamllint', os.path.join(self.wd, 'warn.yaml')])
+            [PYTHON, '-m', 'yamllint', os.path.join(self.wd, 'warn.yaml')])
         lines = out.decode().splitlines()
         self.assertIn('/warn.yaml', lines[0])
         self.assertEqual('\n'.join(lines[1:]),
@@ -71,7 +74,7 @@ class ModuleTestCase(unittest.TestCase):
 
     def test_run_module_on_dir(self):
         with self.assertRaises(subprocess.CalledProcessError) as ctx:
-            subprocess.check_output(['python', '-m', 'yamllint', self.wd])
+            subprocess.check_output([PYTHON, '-m', 'yamllint', self.wd])
         self.assertEqual(ctx.exception.returncode, 1)
 
         files = ctx.exception.output.decode().split('\n\n')

tests/test_parser.py

@@ -18,7 +18,7 @@ import sys
 try:
     assert sys.version_info >= (2, 7)
     import unittest
-except:
+except AssertionError:
     import unittest2 as unittest
 
 import yaml

yamllint/__init__.py

@@ -22,7 +22,7 @@ indentation, etc."""
 
 
 APP_NAME = 'yamllint'
-APP_VERSION = '1.9.0'
+APP_VERSION = '1.11.0'
 APP_DESCRIPTION = __doc__
 
 __author__ = u'Adrien Vergé'

yamllint/cli.py

@@ -16,9 +16,9 @@
 
 from __future__ import print_function
 
-import os.path
+import os
 import sys
-
+import platform
 import argparse
 
 from yamllint import APP_DESCRIPTION, APP_NAME, APP_VERSION
@@ -38,6 +38,15 @@ def find_files_recursively(items):
             yield item
 
 
+def supports_color():
+    supported_platform = not (platform.system() == 'Windows' and not
+                              ('ANSICON' in os.environ or
+                               ('TERM' in os.environ and
+                                os.environ['TERM'] == 'ANSI')))
+    return (supported_platform and
+            hasattr(sys.stdout, 'isatty') and sys.stdout.isatty())
+
+
 class Format(object):
     @staticmethod
     def parsable(problem, filename):
@@ -134,7 +143,7 @@ def run(argv=None):
                 for problem in linter.run(f, conf, filepath):
                     if args.format == 'parsable':
                         print(Format.parsable(problem, file))
-                    elif sys.stdout.isatty():
+                    elif supports_color():
                         if first:
                             print('\033[4m%s\033[0m' % file)
                             first = False

yamllint/conf/default.yaml

@@ -32,6 +32,9 @@ rules:
     max: 2
     max-start: 0
     max-end: 0
+  empty-values:
+    forbid-in-block-mappings: false
+    forbid-in-flow-mappings: false
   hyphens:
     max-spaces-after: 1
   indentation:
@@ -47,6 +50,9 @@ rules:
   new-line-at-end-of-file: enable
   new-lines:
     type: unix
+  octal-values:
+    forbid-implicit-octal: false
+    forbid-explicit-octal: false
   trailing-spaces: enable
   truthy:
     level: warning

yamllint/rules/__init__.py

@@ -24,6 +24,7 @@ from yamllint.rules import (
     document_end,
     document_start,
     empty_lines,
+    empty_values,
     hyphens,
     indentation,
     key_duplicates,
@@ -31,6 +32,7 @@ from yamllint.rules import (
     line_length,
     new_line_at_end_of_file,
     new_lines,
+    octal_values,
     trailing_spaces,
     truthy,
 )
@@ -45,6 +47,7 @@ _RULES = {
     document_end.ID: document_end,
     document_start.ID: document_start,
     empty_lines.ID: empty_lines,
+    empty_values.ID: empty_values,
     hyphens.ID: hyphens,
     indentation.ID: indentation,
     key_duplicates.ID: key_duplicates,
@@ -52,6 +55,7 @@ _RULES = {
     line_length.ID: line_length,
     new_line_at_end_of_file.ID: new_line_at_end_of_file,
     new_lines.ID: new_lines,
+    octal_values.ID: octal_values,
     trailing_spaces.ID: trailing_spaces,
     truthy.ID: truthy,
 }

yamllint/rules/empty_values.py

@@ -0,0 +1,94 @@
+# -*- coding: utf-8 -*-
+# Copyright (C) 2017 Greg Dubicki
+#
+# 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 prevent nodes with empty content, that implicitly result in
+``null`` values.
+
+.. rubric:: Options
+
+* Use ``forbid-in-block-mappings`` to prevent empty values in block mappings.
+* Use ``forbid-in-flow-mappings`` to prevent empty values in flow mappings.
+
+.. rubric:: Examples
+
+#. With ``empty-values: {forbid-in-block-mappings: true}``
+
+   the following code snippets would **PASS**:
+   ::
+
+    some-mapping:
+      sub-element: correctly indented
+
+   ::
+
+    explicitly-null: null
+
+   the following code snippets would **FAIL**:
+   ::
+
+    some-mapping:
+    sub-element: incorrectly indented
+
+   ::
+
+    implicitly-null:
+
+#. With ``empty-values: {forbid-in-flow-mappings: true}``
+
+   the following code snippet would **PASS**:
+   ::
+
+    {prop: null}
+    {a: 1, b: 2, c: 3}
+
+   the following code snippets would **FAIL**:
+   ::
+
+    {prop: }
+
+   ::
+
+    {a: 1, b:, c: 3}
+
+"""
+
+import yaml
+
+from yamllint.linter import LintProblem
+
+
+ID = 'empty-values'
+TYPE = 'token'
+CONF = {'forbid-in-block-mappings': bool,
+        'forbid-in-flow-mappings': bool}
+
+
+def check(conf, token, prev, next, nextnext, context):
+
+    if conf['forbid-in-block-mappings']:
+        if isinstance(token, yaml.ValueToken) and isinstance(next, (
+                yaml.KeyToken, yaml.BlockEndToken)):
+            yield LintProblem(token.start_mark.line + 1,
+                              token.end_mark.column + 1,
+                              'empty value in block mapping')
+
+    if conf['forbid-in-flow-mappings']:
+        if isinstance(token, yaml.ValueToken) and isinstance(next, (
+                yaml.FlowEntryToken, yaml.FlowMappingEndToken)):
+            yield LintProblem(token.start_mark.line + 1,
+                              token.end_mark.column + 1,
+                              'empty value in flow mapping')

yamllint/rules/octal_values.py

@@ -0,0 +1,93 @@
+# -*- coding: utf-8 -*-
+# Copyright (C) 2017 ScienJus
+#
+# 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 prevent values with octal numbers. In YAML, numbers that
+start with ``0`` are interpreted as octal, but this is not always wanted.
+For instance ``010`` is the city code of Beijing, and should not be
+converted to ``8``.
+
+.. rubric:: Examples
+
+#. With ``octal-values: {forbid-implicit-octal: true}``
+
+   the following code snippets would **PASS**:
+   ::
+
+    user:
+      city-code: '010'
+
+   the following code snippets would **PASS**:
+   ::
+
+    user:
+      city-code: 010,021
+
+   the following code snippets would **FAIL**:
+   ::
+
+    user:
+      city-code: 010
+
+#. With ``octal-values: {forbid-explicit-octal: true}``
+
+   the following code snippets would **PASS**:
+   ::
+
+    user:
+      city-code: '0o10'
+
+   the following code snippets would **FAIL**:
+   ::
+
+    user:
+      city-code: 0o10
+"""
+
+import yaml
+
+from yamllint.linter import LintProblem
+
+
+ID = 'octal-values'
+TYPE = 'token'
+CONF = {'forbid-implicit-octal': bool,
+        'forbid-explicit-octal': bool}
+
+
+def check(conf, token, prev, next, nextnext, context):
+    if prev and isinstance(prev, yaml.tokens.TagToken):
+        return
+
+    if conf['forbid-implicit-octal']:
+        if isinstance(token, yaml.tokens.ScalarToken):
+            if not token.style:
+                val = token.value
+                if val.isdigit() and len(val) > 1 and val[0] == '0':
+                    yield LintProblem(
+                        token.start_mark.line + 1, token.end_mark.column + 1,
+                        'forbidden implicit octal value "%s"' %
+                        token.value)
+
+    if conf['forbid-explicit-octal']:
+        if isinstance(token, yaml.tokens.ScalarToken):
+            if not token.style:
+                val = token.value
+                if len(val) > 2 and val[:2] == '0o' and val[2:].isdigit():
+                    yield LintProblem(
+                        token.start_mark.line + 1, token.end_mark.column + 1,
+                        'forbidden explicit octal value "%s"' %
+                        token.value)