fix(signals): patchState does not block on error - #5184
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Signals can throw an error if they are accessed. `patchState` needs to call `getState` in order to provide the current state to an updater function. This fix catches errors in the internal `getState` call and keeps the errored signals in a proxy, where accessing them throws again. That means `patchState` does not block unrelated updates, and the user can apply the normal error handling features like `try/catch`, `ErrorHandler`, or the upcoming error boundaries.
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| for (const key of Reflect.ownKeys(newState)) { | ||
| if (stateKeys.includes(key)) { | ||
| const signalKey = key as keyof State; | ||
| if (currentState[signalKey] !== newState[signalKey]) { |
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Is there a reason why the equality check is removed? This will now also invoke the setter of unchanged state keys.
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| for (const key of touchedKeys) { | ||
| if (stateKeys.includes(key as string | symbol)) { | ||
| signals[key].set(draftState[key]); |
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An AI review flagged a potential regression.
Is this intended, or should we add this to the breaking changes?
it('applies linked state updates after their source updates', () => {
const numberStore = signalStoreFeature(
withState({ id: 1 }),
withLinkedState(({ id }) => ({
level: () => id() * 2,
}))
)(getInitialInnerStore());
patchState(numberStore, { level: 5, id: 2 });
// This succeeded before, but now resolves in { id: 2, level: 4 }
expect(getState(numberStore)).toEqual({ id: 2, level: 5 });
});It has to do with the order in which we set the values. Doing patchState(numberStore, { id: 2, level: 5 }); is fine.
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Signals can throw an error if they are accessed.
patchStateneeds to callgetStatein order to provide the current state to an updater function.This fix catches errors in the internal
getStatecall and keeps the errored signals in a proxy, where accessing them throws again.That means
patchStatedoes not block unrelated updates, and the user can apply the normal error handling features liketry/catch,ErrorHandler, or the upcoming error boundaries.PR Checklist
Please check if your PR fulfills the following requirements:
PR Type
What kind of change does this PR introduce?
What is the current behavior?
Closes #5183
Does this PR introduce a breaking change?