{"record":{"id":"7af7453183497027","repo":"FyroxEngine/Fyrox","slug":"attempt-to-get-reference-to-resource-data-which-fa-7af745","errorCode":null,"errorMessage":"Attempt to get reference to resource data which failed to load!","messagePattern":"Attempt to get reference to resource data which failed to load!","errorType":"panic","errorClass":null,"httpStatus":null,"severity":"critical","filePath":"fyrox-resource/src/lib.rs","lineNumber":642,"sourceCode":"        }\n    }\n}\n\nimpl<T> DerefMut for ResourceDataRef<'_, T>\nwhere\n    T: TypedResourceData,\n{\n    fn deref_mut(&mut self) -> &mut Self::Target {\n        let header = &mut *self.guard;\n        match header.state {\n            ResourceState::Unloaded => {\n                panic!(\"Attempt to get reference to resource data while it is unloaded!\")\n            }\n            ResourceState::Pending { .. } => {\n                panic!(\"Attempt to get reference to resource data while it is loading!\")\n            }\n            ResourceState::LoadError { .. } => {\n                panic!(\"Attempt to get reference to resource data which failed to load!\")\n            }\n            ResourceState::Ok { ref mut data, .. } => (data.inner_mut() as &mut dyn Any)\n                .downcast_mut()\n                .expect(\"Type mismatch!\"),\n        }\n    }\n}\n\n/// Collects all resources used by a given entity. Internally, it uses reflection to iterate over\n/// each field of every descendant sub-object of the entity. This function could be used to collect\n/// all resources used by an object, which could be useful if you're building a resource dependency\n/// analyzer.\npub fn collect_used_resources(\n    entity: &dyn Reflect,\n    resources_collection: &mut FxHashSet<UntypedResource>,\n) {\n    #[inline(always)]\n    fn type_is<T: Reflect>(entity: &dyn Reflect) -> bool {","sourceCodeStart":624,"sourceCodeEnd":660,"githubUrl":"https://github.com/FyroxEngine/Fyrox/blob/76c91aad8eca488ce527b1af707be8b3b24ad72d/fyrox-resource/src/lib.rs#L624-L660","documentation":"Same guard as the other state checks in deref_mut(): when the resource's load attempt failed, ResourceState::LoadError holds an error, not data. Handing out &mut T is impossible, so the code panics with this message.","triggerScenarios":"Calling deref_mut()/data_mut() on a resource handle whose load previously failed (file missing, parse error, unsupported format), leaving it in ResourceState::LoadError.","commonSituations":"Typos in asset paths or extensions; asset files deleted/moved after being referenced; malformed resource files; running a packaged game without including assets; missing resource loader registration for the extension.","solutions":["Inspect the LoadError payload before touching data: match on resource.state() and log/fix the underlying io/parse error.","Fix the asset path/extension or re-add the missing file so the load can succeed.","Register the correct ResourceLoader in ResourceManagerBuilder so the extension maps to a loader.","Re-request the resource after fixing the cause; failed loads are not automatically retried."],"exampleFix":"// before\nlet mut data = model.data_mut(); // panics if load failed\n// after\nif let ResourceState::LoadError { error, .. } = &*model.state() {\n    eprintln!(\"model failed to load: {error}\");\n    return;\n}\nlet mut data = model.data_mut();","handlingStrategy":"validation","validationCode":"fn resource_ok<T: ResourceData>(r: &Resource<T>) -> bool {\n    matches!(&*r.state(), ResourceState::Ok { .. })\n}","typeGuard":"fn load_error<T: ResourceData>(r: &Resource<T>) -> Option<String> {\n    if let ResourceState::LoadError { error, .. } = &*r.state() { Some(error.to_string()) } else { None }\n}","tryCatchPattern":null,"preventionTips":["Check state() for LoadError and log the inner error before accessing data.","Validate asset paths at build/startup time.","Keep assets in the packaged build (CI check for referenced resources).","Register all needed loaders in ResourceManagerBuilder."],"tags":["rust","panic","load-error","resource-state","fyrox"],"backgroundTag":"resource-not-found","analyzedSha":"76c91aad8eca488ce527b1af707be8b3b24ad72d","analyzedAt":"2026-09-10T16:04:01.633Z","contentChangedAt":"2026-09-10T16:04:01.633Z","schemaVersion":2},"datasetVersion":"2026-09-16T09:17:16.951Z"}