{"record":{"id":"d19e5f954f124cfa","repo":"bevyengine/bevy","slug":"expected-the-root-loadeduntypedhandle-to-hold-a-handle-to","errorCode":null,"errorMessage":"Expected the root LoadedUntypedHandle to hold a handle to its subasset, but it did not have such a subasset","messagePattern":"Expected the root LoadedUntypedHandle to hold a handle to its subasset, but it did not have such a subasset","errorType":"exception","errorClass":"ReflectedRonSerializeError::MissingSubasset","httpStatus":null,"severity":"error","filePath":"crates/bevy_asset/src/common_loaders/ron.rs","lineNumber":475,"sourceCode":"    #[error(\"Attempted to load type \\\"{0}\\\", which does not have `ReflectFromReflect` in the type registry. This may occur for types that have opted-out of `FromReflect`\")]\n    MissingReflectFromReflect(&'static str),\n    #[error(\"Attempted to load type \\\"{0}\\\", which does not have `ReflectAsset` in the type registry. Make sure to add `#[reflect(Asset)]` to your type\")]\n    MissingReflectAsset(&'static str),\n}\n\n/// An error type for RON saving.\n#[derive(Error, Debug)]\npub enum RonSerializeError {\n    #[error(transparent)]\n    IoError(#[from] std::io::Error),\n    #[error(transparent)]\n    Ron(#[from] ron::Error),\n}\n\n/// An error type for RON saving using reflection.\n#[derive(Error, Debug)]\npub enum ReflectedRonSerializeError {\n    #[error(\n        \"Expected the root LoadedUntypedHandle to hold a handle to its subasset, but it did not have such a subasset\"\n    )]\n    MissingSubasset,\n    #[error(\"Subasset type was not registered in the TypeRegistry. Ensure your subasset's type implements Reflect (and if it's generic it needs to be manually registered)\")]\n    ValueNotReflect,\n    #[error(\"Subasset type does not have ReflectFromPtr registered in its type data\")]\n    MissingReflectFromPtr,\n    #[error(transparent)]\n    Ron(#[from] RonSerializeError),\n}\n\n#[cfg(test)]\nmod tests {\n    use std::path::Path;\n\n    use alloc::{string::String, vec};\n\n    use bevy_ecs::reflect::AppTypeRegistry;","sourceCodeStart":457,"sourceCodeEnd":493,"githubUrl":"https://github.com/bevyengine/bevy/blob/a62cce8c05ceacd3bd102e678c83e2b42e5dfbe2/crates/bevy_asset/src/common_loaders/ron.rs#L457-L493","documentation":"ReflectedRonSerializeError::MissingSubasset is thrown by the reflected RON saver when the root LoadedUntypedHandle is expected to contain a handle to its subasset but none is present. The serializer needs the typed subasset handle to reach the actual value to serialize.","triggerScenarios":"Calling save/reflected RON serialization on an asset whose LoadedUntypedHandle has no subasset handle attached (asset loaded by a non-reflected path or handle never inserted).","commonSituations":"Serializing an asset that was constructed manually without going through the reflected loader that populates the subasset; saving before the asset finished loading.","solutions":["Load the asset with the reflected RON loader so the subasset handle is populated before saving","Verify the LoadedUntypedHandle actually points at a loaded asset with a subasset prior to save","Use the correct saver for assets loaded outside the reflected pipeline"],"exampleFix":null,"handlingStrategy":"validation","validationCode":"fn can_save(handle: &LoadedUntypedHandle) -> bool {\n    handle.clone().get::<bevy_asset::Handle<()>>().is_ok() // subasset present\n}","typeGuard":null,"tryCatchPattern":null,"preventionTips":["Only save assets loaded through the reflected loader","Check the asset finished loading before saving"],"tags":["bevy","assets","serialization","ron"],"backgroundTag":"internal-invariant-violation","analyzedSha":"a62cce8c05ceacd3bd102e678c83e2b42e5dfbe2","analyzedAt":"2026-09-19T21:23:06.616Z","contentChangedAt":"2026-09-19T21:23:06.616Z","schemaVersion":2},"datasetVersion":"2026-09-23T08:17:48.524Z"}