1 files changed, 208 insertions, 0 deletions
diff --git a/test/test_matcherrror.py b/test/test_matcherrror.py
new file mode 100644
index 0000000..03d9cbd
--- /dev/null
+++ b/test/test_matcherrror.py
@@ -0,0 +1,208 @@
+"""Tests for MatchError."""
+
+import operator
+from typing import Any, Callable
+
+import pytest
+
+from ansiblelint.errors import MatchError
+from ansiblelint.file_utils import Lintable
+from ansiblelint.rules.no_changed_when import CommandHasChangesCheckRule
+from ansiblelint.rules.partial_become import BecomeUserWithoutBecomeRule
+
+
+class DummyTestObject:
+    """A dummy object for equality tests."""
+
+    def __repr__(self) -> str:
+        """Return a dummy object representation for parametrize."""
+        return f"{self.__class__.__name__}()"
+
+    def __eq__(self, other: object) -> bool:
+        """Report the equality check failure with any object."""
+        return False
+
+    def __ne__(self, other: object) -> bool:
+        """Report the confirmation of inequality with any object."""
+        return True
+
+
+class DummySentinelTestObject:
+    """A dummy object for equality protocol tests with sentinel."""
+
+    def __eq__(self, other: object) -> bool:
+        """Return sentinel as result of equality check w/ anything."""
+        return "EQ_SENTINEL"  # type: ignore[return-value]
+
+    def __ne__(self, other: object) -> bool:
+        """Return sentinel as result of inequality check w/ anything."""
+        return "NE_SENTINEL"  # type: ignore[return-value]
+
+    def __lt__(self, other: object) -> bool:
+        """Return sentinel as result of less than check w/ anything."""
+        return "LT_SENTINEL"  # type: ignore[return-value]
+
+    def __gt__(self, other: object) -> bool:
+        """Return sentinel as result of greater than chk w/ anything."""
+        return "GT_SENTINEL"  # type: ignore[return-value]
+
+
+@pytest.mark.parametrize(
+    ("left_match_error", "right_match_error"),
+    (
+        (MatchError("foo"), MatchError("foo")),
+        (MatchError("a", details="foo"), MatchError("a", details="foo")),
+    ),
+)
+def test_matcherror_compare(
+    left_match_error: MatchError,
+    right_match_error: MatchError,
+) -> None:
+    """Check that MatchError instances with similar attrs are equivalent."""
+    assert left_match_error == right_match_error
+
+
+def test_matcherror_invalid() -> None:
+    """Ensure that MatchError requires message or rule."""
+    with pytest.raises(TypeError):
+        MatchError()  # pylint: disable=pointless-exception-statement
+
+
+@pytest.mark.parametrize(
+    ("left_match_error", "right_match_error"),
+    (
+        # sorting by message
+        (MatchError("z"), MatchError("a")),
+        # filenames takes priority in sorting
+        (
+            MatchError("a", lintable=Lintable("b", content="")),
+            MatchError("a", lintable=Lintable("a", content="")),
+        ),
+        # rule id partial-become > rule id no-changed-when
+        (
+            MatchError(rule=BecomeUserWithoutBecomeRule()),
+            MatchError(rule=CommandHasChangesCheckRule()),
+        ),
+        # details are taken into account
+        (MatchError("a", details="foo"), MatchError("a", details="bar")),
+        # columns are taken into account
+        (MatchError("a", column=3), MatchError("a", column=1)),
+        (MatchError("a", column=3), MatchError("a")),
+    ),
+)
+class TestMatchErrorCompare:
+    """Test the comparison of MatchError instances."""
+
+    @staticmethod
+    def test_match_error_less_than(
+        left_match_error: MatchError,
+        right_match_error: MatchError,
+    ) -> None:
+        """Check 'less than' protocol implementation in MatchError."""
+        assert right_match_error < left_match_error
+
+    @staticmethod
+    def test_match_error_greater_than(
+        left_match_error: MatchError,
+        right_match_error: MatchError,
+    ) -> None:
+        """Check 'greater than' protocol implementation in MatchError."""
+        assert left_match_error > right_match_error
+
+    @staticmethod
+    def test_match_error_not_equal(
+        left_match_error: MatchError,
+        right_match_error: MatchError,
+    ) -> None:
+        """Check 'not equals' protocol implementation in MatchError."""
+        assert left_match_error != right_match_error
+
+
+@pytest.mark.parametrize(
+    "other",
+    (
+        None,
+        "foo",
+        42,
+        Exception("foo"),
+    ),
+    ids=repr,
+)
+@pytest.mark.parametrize(
+    ("operation", "operator_char"),
+    (
+        pytest.param(operator.le, "<=", id="<="),
+        pytest.param(operator.gt, ">", id=">"),
+    ),
+)
+def test_matcherror_compare_no_other_fallback(
+    other: Any,
+    operation: Callable[..., bool],
+    operator_char: str,
+) -> None:
+    """Check that MatchError comparison with other types causes TypeError."""
+    expected_error = (
+        r"^("
+        r"unsupported operand type\(s\) for {operator!s}:|"
+        r"'{operator!s}' not supported between instances of"
+        r") 'MatchError' and '{other_type!s}'$".format(
+            other_type=type(other).__name__,
+            operator=operator_char,
+        )
+    )
+    with pytest.raises(TypeError, match=expected_error):
+        operation(MatchError("foo"), other)
+
+
+@pytest.mark.parametrize(
+    "other",
+    (
+        None,
+        "foo",
+        42,
+        Exception("foo"),
+        DummyTestObject(),
+    ),
+    ids=repr,
+)
+@pytest.mark.parametrize(
+    ("operation", "expected_value"),
+    (
+        (operator.eq, False),
+        (operator.ne, True),
+    ),
+    ids=("==", "!="),
+)
+def test_matcherror_compare_with_other_fallback(
+    other: object,
+    operation: Callable[..., bool],
+    expected_value: bool,
+) -> None:
+    """Check that MatchError comparison runs other types fallbacks."""
+    assert operation(MatchError(message="foo"), other) is expected_value
+
+
+@pytest.mark.parametrize(
+    ("operation", "expected_value"),
+    (
+        (operator.eq, "EQ_SENTINEL"),
+        (operator.ne, "NE_SENTINEL"),
+        # NOTE: these are swapped because when we do `x < y`, and `x.__lt__(y)`
+        # NOTE: returns `NotImplemented`, Python will reverse the check into
+        # NOTE: `y > x`, and so `y.__gt__(x) is called.
+        # Ref: https://docs.python.org/3/reference/datamodel.html#object.__lt__
+        (operator.lt, "GT_SENTINEL"),
+        (operator.gt, "LT_SENTINEL"),
+    ),
+    ids=("==", "!=", "<", ">"),
+)
+def test_matcherror_compare_with_dummy_sentinel(
+    operation: Callable[..., bool],
+    expected_value: str,
+) -> None:
+    """Check that MatchError comparison runs other types fallbacks."""
+    dummy_obj = DummySentinelTestObject()
+    # NOTE: This assertion abuses the CPython property to cache short string
+    # NOTE: objects because the identity check is more precise and we don't
+    # NOTE: want extra operator protocol methods to influence the test.
+    assert operation(MatchError("foo"), dummy_obj) is expected_value  # type: ignore[comparison-overlap]