1 files changed, 53 insertions, 0 deletions
diff --git a/src/ansiblelint/rules/playbook_extension.py b/src/ansiblelint/rules/playbook_extension.py
new file mode 100644
index 0000000..491b1fc
--- /dev/null
+++ b/src/ansiblelint/rules/playbook_extension.py
@@ -0,0 +1,53 @@
+"""Implementation of playbook-extension rule."""
+# Copyright (c) 2016, Tsukinowa Inc. <info@tsukinowa.jp>
+# Copyright (c) 2018, Ansible Project
+from __future__ import annotations
+
+import os
+import sys
+
+from ansiblelint.errors import MatchError
+from ansiblelint.file_utils import Lintable
+from ansiblelint.rules import AnsibleLintRule
+from ansiblelint.runner import Runner
+
+
+class PlaybookExtensionRule(AnsibleLintRule):
+    """Use ".yml" or ".yaml" playbook extension."""
+
+    id = "playbook-extension"
+    description = 'Playbooks should have the ".yml" or ".yaml" extension'
+    severity = "MEDIUM"
+    tags = ["formatting"]
+    done: list[str] = []
+    version_added = "v4.0.0"
+
+    def matchyaml(self, file: Lintable) -> list[MatchError]:
+        result: list[MatchError] = []
+        if file.kind != "playbook":
+            return result
+        path = str(file.path)
+        ext = os.path.splitext(path)
+        if ext[1] not in [".yml", ".yaml"] and path not in self.done:
+            self.done.append(path)
+            result.append(self.create_matcherror(filename=file))
+        return result
+
+
+if "pytest" in sys.modules:  # noqa: C901
+    import pytest
+
+    from ansiblelint.rules import RulesCollection  # pylint: disable=ungrouped-imports
+
+    @pytest.mark.parametrize(
+        ("file", "expected"),
+        (pytest.param("examples/playbooks/play-without-extension", 1, id="fail"),),
+    )
+    def test_playbook_extension(file: str, expected: int) -> None:
+        """The ini_file module does not accept preserve mode."""
+        rules = RulesCollection()
+        rules.register(PlaybookExtensionRule())
+        results = Runner(Lintable(file, kind="playbook"), rules=rules).run()
+        assert len(results) == expected
+        for result in results:
+            assert result.tag == "playbook-extension"