fix(router): queue rejections in firstValueFrom to avoid unhandled rejections#66542
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arturovt wants to merge 1 commit intoangular:mainfrom
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fix(router): queue rejections in firstValueFrom to avoid unhandled rejections#66542arturovt wants to merge 1 commit intoangular:mainfrom
arturovt wants to merge 1 commit intoangular:mainfrom
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…jections When an Observable passed to firstValueFrom() errors synchronously (e.g., canMatch guard completes without emitting), the Promise rejects before the caller can attach a .catch() handler. Zone.js detects this as an unhandled rejection and re-throws the error, even though it's properly handled in processSegment's try-catch. Use queueMicrotask() to defer the rejection, ensuring the catch handler is attached before Zone.js performs its unhandled rejection check.
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@atscott as discussed, just leaving a draft if we could consider accept it as a potential fix. |
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As I mentioned, I don't quite follow the reasoning here. I can't reproduce it in the Router or in a simpler reproduction that "synchronously" returns a |
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When an Observable passed to firstValueFrom() errors synchronously (e.g., canMatch guard completes without emitting), the Promise rejects before the caller can attach a .catch() handler. Zone.js detects this as an unhandled rejection and re-throws the error, even though it's properly handled in processSegment's try-catch.
Use queueMicrotask() to defer the rejection, ensuring the catch handler is attached before Zone.js performs its unhandled rejection check.