Also require capability for Fn::Transform usage

simonrw · simonrw · commit 542955cb32b8 · 2025-07-23T15:30:23.000+01:00
diff --git a/localstack-core/localstack/services/cloudformation/v2/provider.py b/localstack-core/localstack/services/cloudformation/v2/provider.py
@@ -477,9 +477,8 @@ def create_stack(self, context: RequestContext, request: CreateStackInput) -> Cr
         template_body = api_utils.extract_template_body(request)
         structured_template = template_preparer.parse_template(template_body)
 
-        if (
-            "CAPABILITY_AUTO_EXPAND" not in request.get("Capabilities", [])
-            and "Transform" in structured_template.keys()
+        if "CAPABILITY_AUTO_EXPAND" not in request.get("Capabilities", []) and (
+            "Transform" in structured_template.keys() or "Fn::Transform" in template_body
         ):
             raise InsufficientCapabilitiesException(
                 "Requires capabilities : [CAPABILITY_AUTO_EXPAND]"
@@ -689,9 +688,8 @@ def update_stack(
         template_body = api_utils.extract_template_body(request)
         structured_template = template_preparer.parse_template(template_body)
 
-        if (
-            "CAPABILITY_AUTO_EXPAND" not in request.get("Capabilities", [])
-            and "Transform" in structured_template.keys()
+        if "CAPABILITY_AUTO_EXPAND" not in request.get("Capabilities", []) and (
+            "Transform" in structured_template.keys() or "Fn::Transform" in template_body
         ):
             raise InsufficientCapabilitiesException(
                 "Requires capabilities : [CAPABILITY_AUTO_EXPAND]"
