microsoft / microsoft/TypeScript

Confusing error message for labels used before definition

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Domain: Error Messages Effort: Moderate Experience Enhancement Good First Issue Help Wanted Suggestion
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Description

The following gives me an unexpected "TS1007: Jump target cannot cross function boundary error" in TS 3.3.33333

function foo() {
    for (let i = 0; i < 10; i++) {
        console.log(`${i}`);
        continue loopend;
    }

    loopend:
    console.log('end of loop');
}

Further investigation... you can jump to the start of the loop, so the error I would argue is that the error message is confusing.

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Research direction

Reproduce the example from the issue in the TypeScript Playground or with TypeScript 3.3.33333, then trace the diagnostic reported as TS1007. Compare the reported jump-target error with the demonstrated label behavior; done means the diagnostic accurately explains this case or points to the actual restriction.

Written by the indexing model from the issue text.

Assessment

Tech stack
typescript
Domain
compilers
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Active
Clarity
Mostly clear
Newbie friendliness
55/100

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