Add rule violations from Yamllint

Also detect yamllint rule violations when this is found as
installed. This will allow us to remove a set of rules that
overlapped with general YAML syntax ones.

Fixes: #953

.ansible-lint

@@ -1,2 +1,9 @@
+extends: default
+rules:
+  document-start: disable
+  # 160 chars was the default used by old E204 rule, but
+  # you can easily change it or disable in your .yamllint file.
+  line-length:
+    max: 160
 exclude_paths:
 - .github/

.pre-commit-config.yaml

@@ -69,6 +69,7 @@ repos:
     args: []
     additional_dependencies:
     - Sphinx>=3.1.2
+    - yamllint
 - repo: https://github.com/pre-commit/mirrors-pylint
   rev: v2.6.0
   hooks:

.yamllint

@@ -1,4 +1,9 @@
 rules:
+  document-start: disable
   indentation:
     level: error
     indent-sequences: consistent
+ignore: |
+  .tox
+  examples/example.yml
+# ignore added because this file includes on-purpose errors

examples/example.yml

@@ -33,8 +33,8 @@
     - name: passing git as an argument to another task
       action: debug msg="{{item}}"
       with_items: 
-        - git
-        - bobbins
+      - git  # yamllint wrong indentation
+      - bobbins
 
     - name: yum latest
       yum: state=latest name=httpd

lib/ansiblelint/rules/YamllintRule.py

@@ -0,0 +1,94 @@
+import logging
+import os
+import sys
+from typing import TYPE_CHECKING, List
+
+from ansiblelint.rules import AnsibleLintRule
+from ansiblelint.skip_utils import get_rule_skips_from_line
+
+if TYPE_CHECKING:
+    from ansiblelint.errors import MatchError
+
+_logger = logging.getLogger(__name__)
+
+# yamllint is a soft-dependency (not installed by default)
+try:
+    from yamllint.config import YamlLintConfig
+    from yamllint.linter import run as run_yamllint
+except ImportError:
+    pass
+
+
+YAMLLINT_CONFIG = """
+extends: default
+rules:
+  document-start: disable
+  # 160 chars was the default used by old E204 rule, but
+  # you can easily change it or disable in your .yamllint file.
+  line-length:
+    max: 160
+"""
+
+DESCRIPTION = """\
+Rule violations reported by YamlLint when this is installed.
+
+You can fully disable all of them by adding `YAML` to the `skip_list`.
+
+Specific tag identifiers that are printed at the end of rule name,
+like `trailing-spaces` or `indentation` can also be be skipped, allowing
+you to have a more fine control.
+"""
+
+
+class YamllintRule(AnsibleLintRule):
+    id = 'YAML'
+    shortdesc = 'Violations reported by yamllint'
+    description = DESCRIPTION
+    severity = 'VERY_LOW'
+    tags = ['formatting', 'experimental', 'yamllint']
+    version_added = 'v5.0.0'
+    config = None
+    if "yamllint.config" in sys.modules:
+        config = YamlLintConfig(content=YAMLLINT_CONFIG)
+        # if we detect local yamllint config we use it but raise a warning
+        # as this is likely to get out of sync with our internal config.
+        for file in ['.yamllint', '.yamllint.yaml', '.yamllint.yml']:
+            if os.path.isfile(file):
+                _logger.warning(
+                    "Loading custom %s config file, this extends our "
+                    "internal yamllint config.",
+                    file)
+                config_override = YamlLintConfig(file=file)
+                config_override.extend(config)
+                break
+        _logger.debug("Effective yamllint rules used: %s", config.rules)
+
+    def __init__(self) -> None:
+        """Construct a rule instance."""
+        # customize id by adding the one reported by yamllint
+        self.id = self.__class__.id
+
+    def matchyaml(self, file, text: str) -> List["MatchError"]:
+        """Return matches found for a specific YAML text."""
+        matches = []
+        filtered_matches = []
+
+        if YamllintRule.config:
+            for p in run_yamllint(text, YamllintRule.config):
+                matches.append(
+                    self.create_matcherror(
+                        message=p.desc,
+                        linenumber=p.line,
+                        details="",
+                        filename=file['path'],
+                        tag=p.rule))
+
+        if matches:
+            lines = text.splitlines()
+            for match in matches:
+                # rule.linenumber starts with 1, not zero
+                skip_list = get_rule_skips_from_line(lines[match.linenumber-1])
+                # print(skip_list)
+                if match.rule.id not in skip_list and match.tag not in skip_list:
+                    filtered_matches.append(match)
+        return filtered_matches

mypy.ini

@@ -35,3 +35,6 @@ ignore_missing_imports = True
 
 [mypy-sphinx_ansible_theme]
 ignore_missing_imports = True
+
+[mypy-yamllint.*]
+ignore_missing_imports = True

setup.cfg

@@ -95,6 +95,9 @@ core =
 # will install ansible from devel branch, may break at any moment.
 devel =
   ansible-core @ git+https://github.com/ansible/ansible.git
+# yamllint must remain optional
+yamllint =
+  yamllint >= 1.25.0  # GPL
 
 [options.packages.find]
 where = lib

test/TestAnsibleSyntax.py

@@ -4,7 +4,7 @@
 when encountering what counts as valid Ansible syntax.
 """
 
-PB_WITH_NULL_TASKS = '''
+PB_WITH_NULL_TASKS = '''\
 - hosts: all
   tasks:
 '''

test/TestExamples.py

@@ -5,7 +5,7 @@
 def test_example(default_rules_collection):
     """example.yml is expected to have 15 match errors inside."""
     result = Runner(default_rules_collection, 'examples/example.yml', [], [], []).run()
-    assert len(result) == 15
+    assert len(result) == 16
 
 
 def test_example_plain_string(default_rules_collection):

test/TestLineTooLong.py

@@ -2,10 +2,10 @@
 import unittest
 
 from ansiblelint.rules import RulesCollection
-from ansiblelint.rules.LineTooLongRule import LineTooLongRule
+from ansiblelint.rules.YamllintRule import YamllintRule
 from ansiblelint.testing import RunFromText
 
-LONG_LINE = '''
+LONG_LINE = '''\
 - name: task example
   debug:
     msg: 'Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua tempor incididunt ut labore et dolore'
@@ -14,7 +14,7 @@
 
 class TestLineTooLongRule(unittest.TestCase):
     collection = RulesCollection()
-    collection.register(LineTooLongRule())
+    collection.register(YamllintRule())
 
     def setUp(self):
         self.runner = RunFromText(self.collection)

test/TestMissingFilePermissionsRule.py

@@ -22,7 +22,7 @@
 
 from ansiblelint.rules.MissingFilePermissionsRule import MissingFilePermissionsRule
 
-SUCCESS_TASKS = '''
+SUCCESS_TASKS = '''\
 ---
 - hosts: hosts
   tasks:
@@ -56,7 +56,7 @@
         recurse: yes
 '''
 
-FAIL_TASKS = '''
+FAIL_TASKS = '''\
 ---
 - hosts: hosts
   tasks:
@@ -105,10 +105,10 @@ def test_fail(rule_runner):
     """Validate that missing mode triggers the rule."""
     results = rule_runner.run_playbook(FAIL_TASKS)
     assert len(results) == 5
-    assert results[0].linenumber == 5
-    assert results[1].linenumber == 9
-    assert results[2].linenumber == 13
-    # assert results[3].linenumber == 17
-    assert results[3].linenumber == 21
-    assert results[4].linenumber == 26
-    # assert results[6].linenumber == 30
+    assert results[0].linenumber == 4
+    assert results[1].linenumber == 8
+    assert results[2].linenumber == 12
+    # assert results[3].linenumber == 16
+    assert results[3].linenumber == 20
+    assert results[4].linenumber == 25
+    # assert results[6].linenumber == 29

test/TestSkipInsideYaml.py

@@ -49,13 +49,13 @@
       become_user: alice
       action: git
 
-    - name: test 204 and 206
+    - name: test YAML and 206
       get_url:
         url: http://example.com/really_long_path/really_long_path/really_long_path/really_long_path/really_long_path/really_long_path/really_long_path/really_long_path/file.conf
         dest: "{{dest_proj_path}}/foo.conf"
-    - name: test 204 and 206 (skipped)
+    - name: test YAML and 206 (skipped)
       get_url:
-        url: http://example.com/really_long_path/really_long_path/really_long_path/really_long_path/really_long_path/really_long_path/really_long_path/really_long_path/file.conf  # noqa 204
+        url: http://example.com/really_long_path/really_long_path/really_long_path/really_long_path/really_long_path/really_long_path/really_long_path/really_long_path/file.conf  # noqa YAML
         dest: "{{dest_proj_path}}/foo.conf"  # noqa 206
 
     - name: test 302

test/TestSkipPlaybookItems.py

@@ -1,6 +1,6 @@
 import pytest
 
-PLAYBOOK_PRE_TASKS = '''
+PLAYBOOK_PRE_TASKS = '''\
 - hosts: all
   tasks:
     - name: bad git 1  # noqa 401
@@ -14,7 +14,7 @@
       action: git a=b c=d
 '''
 
-PLAYBOOK_POST_TASKS = '''
+PLAYBOOK_POST_TASKS = '''\
 - hosts: all
   tasks:
     - name: bad git 1  # noqa 401
@@ -28,7 +28,7 @@
       action: git a=b c=d
 '''
 
-PLAYBOOK_HANDLERS = '''
+PLAYBOOK_HANDLERS = '''\
 - hosts: all
   tasks:
     - name: bad git 1  # noqa 401
@@ -42,7 +42,7 @@
       action: git a=b c=d
 '''
 
-PLAYBOOK_TWO_PLAYS = '''
+PLAYBOOK_TWO_PLAYS = '''\
 - hosts: all
   tasks:
     - name: bad git 1  # noqa 401
@@ -58,29 +58,29 @@
       action: git a=b c=d
 '''
 
-PLAYBOOK_WITH_BLOCK = '''
+PLAYBOOK_WITH_BLOCK = '''\
 - hosts: all
   tasks:
-  - name: bad git 1  # noqa 401
-    action: git a=b c=d
-  - name: bad git 2
-    action: git a=b c=d
-  - name: Block with rescue and always section
-    block:
-      - name: bad git 3  # noqa 401
-        action: git a=b c=d
-      - name: bad git 4
-        action: git a=b c=d
-    rescue:
-      - name: bad git 5  # noqa 401
-        action: git a=b c=d
-      - name: bad git 6
-        action: git a=b c=d
-    always:
-      - name: bad git 7  # noqa 401
-        action: git a=b c=d
-      - name: bad git 8
-        action: git a=b c=d
+    - name: bad git 1  # noqa 401
+      action: git a=b c=d
+    - name: bad git 2
+      action: git a=b c=d
+    - name: Block with rescue and always section
+      block:
+        - name: bad git 3  # noqa 401
+          action: git a=b c=d
+        - name: bad git 4
+          action: git a=b c=d
+      rescue:
+        - name: bad git 5  # noqa 401
+          action: git a=b c=d
+        - name: bad git 6
+          action: git a=b c=d
+      always:
+        - name: bad git 7  # noqa 401
+          action: git a=b c=d
+        - name: bad git 8
+          action: git a=b c=d
 '''