snapshot of https://github.com/zulip/zulip.git @ 48c69911c7dd4e03b20552eb3bd77ad8151c1357 (2026-09-15)

tools/tests/test_zulint_custom_rules.py

@@ -0,0 +1,68 @@
+import os
+from io import StringIO
+from unittest import TestCase
+from unittest.mock import patch
+
+from typing_extensions import override
+from zulint.custom_rules import RuleList
+
+from tools.linter_lib.custom_check import non_py_rules, python_rules
+
+ROOT_DIR = os.path.abspath(os.path.join(__file__, "..", "..", ".."))
+CHECK_MESSAGE = "Fix the corresponding rule in `tools/linter_lib/custom_check.py`."
+
+
+class TestRuleList(TestCase):
+    @override
+    def setUp(self) -> None:
+        all_rules = list(python_rules.rules)
+        for rule in non_py_rules:
+            all_rules.extend(rule.rules)
+        self.all_rules = all_rules
+
+    def test_paths_in_rules(self) -> None:
+        """Verifies that the paths mentioned in linter rules actually exist"""
+        for rule in self.all_rules:
+            for path in rule.get("exclude", {}):
+                abs_path = os.path.abspath(os.path.join(ROOT_DIR, path))
+                self.assertTrue(
+                    os.path.exists(abs_path),
+                    f"'{path}' is neither an existing file, nor a directory. {CHECK_MESSAGE}",
+                )
+
+            for line_tuple in rule.get("exclude_line", {}):
+                path = line_tuple[0]
+                abs_path = os.path.abspath(os.path.join(ROOT_DIR, path))
+                self.assertTrue(
+                    os.path.isfile(abs_path), f"The file '{path}' doesn't exist. {CHECK_MESSAGE}"
+                )
+
+            for path in rule.get("include_only", {}):
+                if not os.path.splitext(path)[1]:
+                    self.assertTrue(
+                        path.endswith("/"),
+                        f"The path '{path}' should end with '/'. {CHECK_MESSAGE}",
+                    )
+
+    def test_rule_patterns(self) -> None:
+        """Verifies that the search regex specified in a custom rule actually matches
+        the expectation and doesn't throw false positives."""
+        for rule in self.all_rules:
+            pattern = rule["pattern"]
+            for line in rule.get("good_lines", []):
+                with patch("builtins.open", return_value=StringIO(line + "\n\n"), autospec=True):
+                    self.assertFalse(
+                        RuleList([], [rule]).custom_check_file("foo.bar", "baz", ""),
+                        f"The pattern '{pattern}' matched the line '{line}' while it shouldn't.",
+                    )
+
+            for line in rule.get("bad_lines", []):
+                for filename in rule.get("include_only", {"foo.bar"}):
+                    with (
+                        patch("builtins.open", return_value=StringIO(line + "\n\n"), autospec=True),
+                        patch("builtins.print"),
+                    ):
+                        self.assertTrue(
+                            RuleList([], [rule]).custom_check_file(filename, "baz", ""),
+                            f"The pattern '{pattern}' didn't match the line '{line}' while it should.",
+                        )