Microsoft/TypeScript
Infer from usages should not widen literal types
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#52 991 ouverte le 27 févr. 2023
Domain: LS: RefactoringsExperience EnhancementHelp WantedSuggestion
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Description
Bug Report
🔎 Search Terms
string literal to string, infer type from usages, code fix, quickfix
⏯ Playground Link
Playground link with relevant code
💻 Code
let a
a = "foo" as "foo" | "bar"
let b
b = getB()
checkB(b)
function checkB(toCheck: "foo" | "bar") {
}
function getB(): "foo" | "bar" {
return "foo"
}
🙁 Actual behavior
After running infer from usages quickfix, you get string type in a and b positions
🙂 Expected behavior
Should get inffered type "foo"
I think in case of as and satisfies clauses the type should be just copied literally?
As you can see from example this is common case for string enums, like when some function expects some string enum instead of just string, but this information gets lost