1 files changed, 156 insertions, 0 deletions
diff --git a/test/test_transformer.py b/test/test_transformer.py
new file mode 100644
index 0000000..4b593c0
--- /dev/null
+++ b/test/test_transformer.py
@@ -0,0 +1,156 @@
+"""Tests for Transformer."""
+from __future__ import annotations
+
+import os
+import pathlib
+import shutil
+from argparse import Namespace
+from typing import Iterator
+
+import pytest
+
+from ansiblelint.rules import RulesCollection
+
+# noinspection PyProtectedMember
+from ansiblelint.runner import LintResult, _get_matches
+from ansiblelint.transformer import Transformer
+
+
+@pytest.fixture(name="copy_examples_dir")
+def fixture_copy_examples_dir(
+    tmp_path: pathlib.Path, config_options: Namespace
+) -> Iterator[tuple[pathlib.Path, pathlib.Path]]:
+    """Fixture that copies the examples/ dir into a tmpdir."""
+    examples_dir = pathlib.Path("examples")
+
+    shutil.copytree(examples_dir, tmp_path / "examples")
+    old_cwd = os.getcwd()
+    try:
+        os.chdir(tmp_path)
+        config_options.cwd = tmp_path
+        yield pathlib.Path(old_cwd), tmp_path
+    finally:
+        os.chdir(old_cwd)
+
+
+@pytest.fixture(name="runner_result")
+def fixture_runner_result(
+    config_options: Namespace,
+    default_rules_collection: RulesCollection,
+    playbook: str,
+) -> LintResult:
+    """Fixture that runs the Runner to populate a LintResult for a given file."""
+    config_options.lintables = [playbook]
+    result = _get_matches(rules=default_rules_collection, options=config_options)
+    return result
+
+
+@pytest.mark.parametrize(
+    ("playbook", "matches_count", "transformed"),
+    (
+        # reuse TestRunner::test_runner test cases to ensure transformer does not mangle matches
+        pytest.param(
+            "examples/playbooks/nomatchestest.yml", 0, False, id="nomatchestest"
+        ),
+        pytest.param("examples/playbooks/unicode.yml", 1, False, id="unicode"),
+        pytest.param(
+            "examples/playbooks/lots_of_warnings.yml", 992, False, id="lots_of_warnings"
+        ),
+        pytest.param("examples/playbooks/become.yml", 0, False, id="become"),
+        pytest.param(
+            "examples/playbooks/contains_secrets.yml", 0, False, id="contains_secrets"
+        ),
+        pytest.param(
+            "examples/playbooks/vars/empty_vars.yml", 0, False, id="empty_vars"
+        ),
+        pytest.param("examples/playbooks/vars/strings.yml", 0, True, id="strings"),
+    ),
+)
+def test_transformer(  # pylint: disable=too-many-arguments, too-many-locals
+    config_options: Namespace,
+    copy_examples_dir: tuple[pathlib.Path, pathlib.Path],
+    playbook: str,
+    runner_result: LintResult,
+    transformed: bool,
+    matches_count: int,
+) -> None:
+    """
+    Test that transformer can go through any corner cases.
+
+    Based on TestRunner::test_runner
+    """
+    setattr(config_options, "write_list", ["all"])
+    transformer = Transformer(result=runner_result, options=config_options)
+    transformer.run()
+
+    matches = runner_result.matches
+    assert len(matches) == matches_count
+
+    orig_dir, tmp_dir = copy_examples_dir
+    orig_playbook = orig_dir / playbook
+    expected_playbook = orig_dir / playbook.replace(".yml", ".transformed.yml")
+    transformed_playbook = tmp_dir / playbook
+
+    orig_playbook_content = orig_playbook.read_text()
+    expected_playbook_content = expected_playbook.read_text()
+    transformed_playbook_content = transformed_playbook.read_text()
+
+    if transformed:
+        assert orig_playbook_content != transformed_playbook_content
+    else:
+        assert orig_playbook_content == transformed_playbook_content
+
+    assert transformed_playbook_content == expected_playbook_content
+
+
+@pytest.mark.parametrize(
+    ("write_list", "expected"),
+    (
+        # 1 item
+        (["all"], {"all"}),
+        (["none"], {"none"}),
+        (["rule-id"], {"rule-id"}),
+        # 2 items
+        (["all", "all"], {"all"}),
+        (["all", "none"], {"none"}),
+        (["all", "rule-id"], {"all"}),
+        (["none", "all"], {"all"}),
+        (["none", "none"], {"none"}),
+        (["none", "rule-id"], {"rule-id"}),
+        (["rule-id", "all"], {"all"}),
+        (["rule-id", "none"], {"none"}),
+        (["rule-id", "rule-id"], {"rule-id"}),
+        # 3 items
+        (["all", "all", "all"], {"all"}),
+        (["all", "all", "none"], {"none"}),
+        (["all", "all", "rule-id"], {"all"}),
+        (["all", "none", "all"], {"all"}),
+        (["all", "none", "none"], {"none"}),
+        (["all", "none", "rule-id"], {"rule-id"}),
+        (["all", "rule-id", "all"], {"all"}),
+        (["all", "rule-id", "none"], {"none"}),
+        (["all", "rule-id", "rule-id"], {"all"}),
+        (["none", "all", "all"], {"all"}),
+        (["none", "all", "none"], {"none"}),
+        (["none", "all", "rule-id"], {"all"}),
+        (["none", "none", "all"], {"all"}),
+        (["none", "none", "none"], {"none"}),
+        (["none", "none", "rule-id"], {"rule-id"}),
+        (["none", "rule-id", "all"], {"all"}),
+        (["none", "rule-id", "none"], {"none"}),
+        (["none", "rule-id", "rule-id"], {"rule-id"}),
+        (["rule-id", "all", "all"], {"all"}),
+        (["rule-id", "all", "none"], {"none"}),
+        (["rule-id", "all", "rule-id"], {"all"}),
+        (["rule-id", "none", "all"], {"all"}),
+        (["rule-id", "none", "none"], {"none"}),
+        (["rule-id", "none", "rule-id"], {"rule-id"}),
+        (["rule-id", "rule-id", "all"], {"all"}),
+        (["rule-id", "rule-id", "none"], {"none"}),
+        (["rule-id", "rule-id", "rule-id"], {"rule-id"}),
+    ),
+)
+def test_effective_write_set(write_list: list[str], expected: set[str]) -> None:
+    """Make sure effective_write_set handles all/none keywords correctly."""
+    actual = Transformer.effective_write_set(write_list)
+    assert actual == expected