Microsoft/TypeScript
Vedi su GitHubAliased optional chain calls don't narrow like their inline equivalents
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#59.145 aperta il 5 lug 2024
Domain: check: Control FlowHelp WantedPossible Improvement
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Descrizione
🔎 Search Terms
aliased conditions control flow analysis cfa optional chain call
🕗 Version & Regression Information
- This is the behavior in every version I tried
⏯ Playground Link
💻 Code
function resolve1(id: string | undefined) {
const isBundled = id?.includes("_bundled");
if (isBundled) {
const str: string = id; // error
}
}
function resolve2(id: string | undefined) {
if (id?.includes("_bundled")) {
const str: string = id; // ok
}
}
🙁 Actual behavior
resolve1 errors within the if block
🙂 Expected behavior
I'd expect it to be OK. Just like resolve2 is OK with it here - the condition is exactly the same and TS supports Control Flow Analysis of Aliased Conditions and Discriminant since 4.4
Additional information about the issue
No response