fix: support finding type annotated resolver

aws_lambda_powertools/event_handler/openapi/merge.py

@@ -67,11 +67,15 @@ def _file_has_resolver(file_path: Path, resolver_name: str) -> bool:
         return False
 
     for node in ast.walk(tree):
+        targets = []
         if isinstance(node, ast.Assign):
-            for target in node.targets:
-                if isinstance(target, ast.Name) and target.id == resolver_name:
-                    if _is_resolver_call(node.value):
-                        return True
+            targets = node.targets
+        elif isinstance(node, ast.AnnAssign):
+            targets = [node.target]
+        for target in targets:
+            if isinstance(target, ast.Name) and target.id == resolver_name:
+                if _is_resolver_call(node.value):
+                    return True
     return False
 
 

tests/unit/event_handler/openapi/test_openapi_merge.py

@@ -57,6 +57,15 @@ def test_file_has_resolver_found(tmp_path: Path):
     assert _file_has_resolver(handler_file, "app") is True
 
 
+def test_file_has_resolver_found_with_type_annotation(tmp_path: Path):
+    handler_file = tmp_path / "handler.py"
+    handler_file.write_text("""
+from aws_lambda_powertools.event_handler import APIGatewayRestResolver
+app: APIGatewayRestResolver = APIGatewayRestResolver()
+""")
+    assert _file_has_resolver(handler_file, "app") is True
+
+
 def test_is_excluded_with_directory_pattern():
     root = Path("/project")
     assert _is_excluded(Path("/project/tests/handler.py"), root, ["**/tests/**"]) is True