Capture python warnings and report them as matches

This change introduces a new way to generate warnings in linter, one
that uses the warnings support in Python. The benefit is that this
allows use to generate warnings from anywhere inside the code without
having to pass them from function to function.

For start we will be using this for internal rules, like ability to
report outdated noqa comments.

Author: ssbarnea

playbook.yml

@@ -2,6 +2,6 @@
 - name: Example
   hosts: localhost
   tasks:
-    - name: include extra tasks
+    - name: include extra tasks # noqa: 102
       ansible.builtin.include_tasks:
         file: /dev/null

src/ansiblelint/errors.py

@@ -9,6 +9,10 @@
 from ansiblelint.file_utils import Lintable, normpath
 
 
+class LintWarning(Warning):
+    """Used by linter."""
+
+
 class StrictModeError(RuntimeError):
     """Raise when we encounter a warning in strict mode."""
 

src/ansiblelint/rules/__init__.py

@@ -121,7 +121,10 @@ def matchlines(self, file: Lintable) -> list[MatchError]:
             if line.lstrip().startswith("#"):
                 continue
 
-            rule_id_list = ansiblelint.skip_utils.get_rule_skips_from_line(line)
+            rule_id_list = ansiblelint.skip_utils.get_rule_skips_from_line(
+                line,
+                lintable=file,
+            )
             if self.id in rule_id_list:
                 continue
 

src/ansiblelint/rules/jinja.py

@@ -200,7 +200,10 @@ def matchyaml(self, file: Lintable) -> list[MatchError]:
                 lines = file.content.splitlines()
                 for match in raw_results:
                     # lineno starts with 1, not zero
-                    skip_list = get_rule_skips_from_line(lines[match.lineno - 1])
+                    skip_list = get_rule_skips_from_line(
+                        line=lines[match.lineno - 1],
+                        lintable=file,
+                    )
                     if match.rule.id not in skip_list and match.tag not in skip_list:
                         results.append(match)
         else:

src/ansiblelint/rules/var_naming.py

@@ -91,7 +91,10 @@ def matchplay(self, file: Lintable, data: dict[str, Any]) -> list[MatchError]:
             lines = file.content.splitlines()
             for match in raw_results:
                 # lineno starts with 1, not zero
-                skip_list = get_rule_skips_from_line(lines[match.lineno - 1])
+                skip_list = get_rule_skips_from_line(
+                    line=lines[match.lineno - 1],
+                    lintable=file,
+                )
                 if match.rule.id not in skip_list and match.tag not in skip_list:
                     results.append(match)
 
@@ -171,7 +174,10 @@ def matchyaml(self, file: Lintable) -> list[MatchError]:
                 lines = file.content.splitlines()
                 for match in raw_results:
                     # lineno starts with 1, not zero
-                    skip_list = get_rule_skips_from_line(lines[match.lineno - 1])
+                    skip_list = get_rule_skips_from_line(
+                        line=lines[match.lineno - 1],
+                        lintable=file,
+                    )
                     if match.rule.id not in skip_list and match.tag not in skip_list:
                         results.append(match)
         else:

src/ansiblelint/runner.py

@@ -5,17 +5,18 @@
 import multiprocessing
 import multiprocessing.pool
 import os
+import warnings
 from collections.abc import Generator
 from dataclasses import dataclass
 from fnmatch import fnmatch
 from typing import TYPE_CHECKING, Any
 
 import ansiblelint.skip_utils
 import ansiblelint.utils
-from ansiblelint._internal.rules import LoadingFailureRule
+from ansiblelint._internal.rules import LoadingFailureRule, WarningRule
 from ansiblelint.config import Options
 from ansiblelint.constants import States
-from ansiblelint.errors import MatchError
+from ansiblelint.errors import LintWarning, MatchError
 from ansiblelint.file_utils import Lintable, expand_dirs_in_lintables
 from ansiblelint.rules.syntax_check import AnsibleSyntaxCheckRule
 
@@ -33,6 +34,14 @@ class LintResult:
     files: set[Lintable]
 
 
+@dataclass
+class Occurrence:
+    """Class that tracks result of linting."""
+
+    file: Lintable
+    lineno: MatchError
+
+
 class Runner:
     """Runner class performs the linting process."""
 
@@ -112,6 +121,38 @@ def is_excluded(self, lintable: Lintable) -> bool:
 
     def run(self) -> list[MatchError]:  # noqa: C901
         """Execute the linting process."""
+        matches: list[MatchError] = []
+        with warnings.catch_warnings(record=True) as captured_warnings:
+            warnings.simplefilter("always")
+            matches = self._run()
+            for warn in captured_warnings:
+                # For the moment we are ignoring deprecation warnings as Ansible
+                # modules outside current content can generate them and user
+                # might not be able to do anything about them.
+                if warn.category is DeprecationWarning:
+                    continue
+                if warn.category is LintWarning:
+                    filename: None | Lintable = None
+                    if isinstance(warn.source, Lintable):
+                        filename = warn.source
+                    match = MatchError(
+                        message=warn.message if isinstance(warn.message, str) else "?",
+                        rule=WarningRule(),
+                        filename=filename,
+                    )
+                    matches.append(match)
+                    continue
+                _logger.warning(
+                    "%s:%s %s %s",
+                    warn.filename,
+                    warn.lineno or 1,
+                    warn.category.__name__,
+                    warn.message,
+                )
+        return matches
+
+    def _run(self) -> list[MatchError]:  # noqa: C901
+        """Internal implementation of run."""
         files: list[Lintable] = []
         matches: list[MatchError] = []
 

src/ansiblelint/skip_utils.py

@@ -24,6 +24,7 @@
 import collections.abc
 import logging
 import re
+import warnings
 from collections.abc import Generator, Sequence
 from functools import cache
 from itertools import product
@@ -42,6 +43,7 @@
     RENAMED_TAGS,
     SKIPPED_RULES_KEY,
 )
+from ansiblelint.errors import LintWarning
 from ansiblelint.file_utils import Lintable
 
 if TYPE_CHECKING:
@@ -57,7 +59,11 @@
 # ansible.parsing.yaml.objects.AnsibleSequence
 
 
-def get_rule_skips_from_line(line: str) -> list[str]:
+def get_rule_skips_from_line(
+    line: str,
+    lintable: Lintable,
+    lineno: int = 1,
+) -> list[str]:
     """Return list of rule ids skipped via comment on the line of yaml."""
     _before_noqa, _noqa_marker, noqa_text = line.partition("# noqa")
 
@@ -66,10 +72,16 @@ def get_rule_skips_from_line(line: str) -> list[str]:
         if v in RENAMED_TAGS:
             tag = RENAMED_TAGS[v]
             if v not in _found_deprecated_tags:
-                _logger.warning(
-                    "Replaced outdated tag '%s' with '%s', replace it to avoid future regressions",
-                    v,
-                    tag,
+                msg = f"Replaced outdated tag '{v}' with '{tag}', replace it to avoid future regressions"
+                warnings.warn(
+                    message=msg,
+                    category=LintWarning,
+                    source={
+                        "filename": lintable,
+                        "lineno": lineno,
+                        "tag": "warning[outdated-tag]",
+                    },
+                    stacklevel=0,
                 )
                 _found_deprecated_tags.add(v)
             v = tag
@@ -253,7 +265,11 @@ def traverse_yaml(obj: Any) -> None:
                     if _noqa_comment_re.match(comment_str):
                         line = v.start_mark.line + 1  # ruamel line numbers start at 0
                         lintable.line_skips[line].update(
-                            get_rule_skips_from_line(comment_str.strip()),
+                            get_rule_skips_from_line(
+                                comment_str.strip(),
+                                lintable=lintable,
+                                lineno=line,
+                            ),
                         )
         yaml_comment_obj_strings.append(str(obj.ca.items))
         if isinstance(obj, dict):
@@ -273,7 +289,7 @@ def traverse_yaml(obj: Any) -> None:
     rule_id_list = []
     for comment_obj_str in yaml_comment_obj_strings:
         for line in comment_obj_str.split(r"\n"):
-            rule_id_list.extend(get_rule_skips_from_line(line))
+            rule_id_list.extend(get_rule_skips_from_line(line, lintable=lintable))
 
     return [normalize_tag(tag) for tag in rule_id_list]
 

test/test_skiputils.py

@@ -42,7 +42,7 @@
 )
 def test_get_rule_skips_from_line(line: str, expected: str) -> None:
     """Validate get_rule_skips_from_line."""
-    v = get_rule_skips_from_line(line)
+    v = get_rule_skips_from_line(line, lintable=Lintable(""))
     assert v == [expected]