test: add modifier ordering rule unit tests

Author: AlbertoCentonze

tests/contracts/test_modifiers_ordering.vy

@@ -0,0 +1,108 @@
+# @version 0.4.2
+
+# Correct ordering examples
+
+@external
+@view
+def correct_external_view() -> uint256:
+    return 42
+
+@internal
+@pure
+def correct_internal_pure() -> uint256:
+    return 123
+
+@external
+@payable
+def correct_external_payable():
+    pass
+
+@external
+@nonreentrant
+def correct_external_nonreentrant():
+    pass
+
+@external
+@view
+@nonreentrant
+def correct_external_view_nonreentrant() -> uint256:
+    return 42
+
+@external
+@payable
+@nonreentrant
+def correct_external_payable_nonreentrant():
+    pass
+
+# Incorrect ordering examples
+
+@view
+@external
+def incorrect_view_external() -> uint256:
+    return 42
+
+@pure
+@internal
+def incorrect_pure_internal() -> uint256:
+    return 123
+
+@nonreentrant
+@external
+def incorrect_nonreentrant_external():
+    pass
+
+@nonreentrant
+@view
+@external
+def incorrect_nonreentrant_view_external() -> uint256:
+    return 42
+
+@payable
+@nonreentrant
+@external
+def incorrect_payable_nonreentrant_external():
+    pass
+
+# Edge cases
+
+@deploy
+def __init__():
+    pass
+
+@external
+def no_other_modifiers():
+    pass
+
+@internal
+def internal_only():
+    pass
+
+# Functions without explicit visibility (defaults to internal)
+
+@pure
+def implicit_internal_pure() -> uint256:
+    return 42
+
+@view
+def implicit_internal_view() -> uint256:
+    return 42
+
+@nonreentrant
+def implicit_internal_nonreentrant():
+    pass
+
+# Incorrect ordering with implicit internal
+
+@nonreentrant
+@view
+def incorrect_implicit_internal_nonreentrant_view() -> uint256:
+    return 42
+
+# Mixed correct and incorrect orderings
+@view
+def implicit_internal_view_correct() -> uint256:
+    return 42
+
+@nonpayable
+def implicit_internal_nonpayable_correct():
+    pass

tests/rules/test_modifiers_ordering.py

@@ -0,0 +1,56 @@
+import pytest
+from natrix import parse_file
+from natrix.rules.modifiers_ordering import ModifiersOrderingRule
+
+
+@pytest.fixture()
+def test_modifiers_ordering_contract():
+    return parse_file("tests/contracts/test_modifiers_ordering.vy")
+
+
+def test_modifiers_ordering(test_modifiers_ordering_contract):
+    rule = ModifiersOrderingRule()
+
+    issues = rule.run(test_modifiers_ordering_contract)
+
+    # We expect 6 issues for the incorrect ordering examples
+    assert len(issues) == 6
+
+    # Check that we found all the incorrect orderings
+    issue_messages = [issue.message for issue in issues]
+
+    # Check specific issues
+    incorrect_functions = [
+        "incorrect_view_external",
+        "incorrect_pure_internal",
+        "incorrect_nonreentrant_external",
+        "incorrect_nonreentrant_view_external",
+        "incorrect_payable_nonreentrant_external",
+        "incorrect_implicit_internal_nonreentrant_view",
+    ]
+
+    for func_name in incorrect_functions:
+        assert any(
+            func_name in msg for msg in issue_messages
+        ), f"Expected issue for {func_name}"
+
+    # Verify the issue details for one specific case
+    view_external_issue = next(
+        (issue for issue in issues if "incorrect_view_external" in issue.message), None
+    )
+    assert view_external_issue is not None
+    assert view_external_issue.code == "NTX12"
+    assert view_external_issue.severity == "style"
+    assert "@view, @external" in view_external_issue.message
+
+    # Verify implicit internal cases
+    implicit_issue = next(
+        (
+            issue
+            for issue in issues
+            if "incorrect_implicit_internal_nonreentrant_view" in issue.message
+        ),
+        None,
+    )
+    assert implicit_issue is not None
+    assert "@nonreentrant, @view" in implicit_issue.message