Microsoft/TypeScript
View on GitHubInferred Promise type breaks ordering of completions
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#56,978 opened on Jan 8, 2024
Domain: LS: Completion ListsExperience EnhancementHelp WantedSuggestion
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Description
🔎 Search Terms
promise, generic, completion, inference
🕗 Version & Regression Information
- This is the behavior in every version I tried, and I reviewed the FAQ for entries about promise/completions (found nothing)
⏯ Playground Link
💻 Code
interface Foo<T> extends Promise<T> {
// This should show up first along with catch, then, finally, etc.
foo(): null;
}
let good: Foo<[]>;
async () => {
// In VS Code, try typing:
//
// good.
}
function bad<T>(x: T): Foo<T> {
return null as any;
}
async () => {
// In VS Code, try typing:
//
// bad([]).
}
🙁 Actual behavior
If a generic is used to infer the type contained in the Promise, then the completions ordering is lost.
This is the correct ordering, foo shows up towards the top:
But if the function returning the Promise subclass is used, the ordering is lost:
🙂 Expected behavior
The methods declared on the Promise and its subclasses / subinterfaces should show up before the "after adding await" properties of whatever is contained in the Promise.
Additional information about the issue
I'd be willing to work on fixing this with some guidance, if it's feasible.