In Inspector.json in any command add to return types anonymous type, for example: { "name": "ret1", "type": "array", "items": { "type": "string", "enum": ["Cat", "Dog"] }} InspectorBackendDispatcher doesn't compile: error: ‘Ret1’ was not declared in this scope Should compile.
Closing as invalid, as this bug pertains to the old inspector UI and/or its tests. Please file a new bug (https://www.webkit.org/new-inspector-bug) if the bug/feature/issue is still relevant to WebKit trunk.