Fix E3031 false positive for boolean values with pattern

src/cfnlint/jsonschema/_keywords.py

@@ -19,6 +19,7 @@
 
 from __future__ import annotations
 
+import json
 from copy import deepcopy
 from difflib import SequenceMatcher
 from typing import Any, Sequence
@@ -644,7 +645,7 @@ def pattern(
         return
 
     if not isinstance(instance, str):
-        instance = str(instance)
+        instance = json.dumps(instance)
 
     if not re.search(patrn, instance):
         yield ValidationError(f"{instance!r} does not match {patrn!r}")

test/unit/module/jsonschema/test_validator.py

@@ -694,7 +694,7 @@ def test_validator(name, schema, instance, expected, validator):
         ),
         (
             "pattern with bool converts to string",
-            {"pattern": "^True$"},
+            {"pattern": "^true$"},
             True,
             [],
         ),

test/unit/rules/resources/properties/test_pattern.py

@@ -48,6 +48,14 @@ def test_validate(rule, validator):
     assert len(errs) == 0
 
 
+def test_validate_boolean(rule, validator):
+    # Boolean True stringifies to "true" via json.dumps, matching "true|false"
+    assert len(list(rule.pattern(validator, "true|false", True, {}))) == 0
+    assert len(list(rule.pattern(validator, "true|false", False, {}))) == 0
+    # Boolean should not match an unrelated pattern
+    assert len(list(rule.pattern(validator, "^foo$", True, {}))) == 1
+
+
 def test_pattern_exceptions(rule, validator):
     rule.configure({"exceptions": ["AWS::"]})