fix(eslint-plugin): [no-unnecessary-type-assertion] false positive on non-null assertion after an implicitly-any variable gets initialised inside conditional block #11082
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## main #11082 +/- ##
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Coverage 90.82% 90.82%
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Branches 8274 8275 +1
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| if (declaration.type == null) { | ||
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We're definitely in the right ballpark, but I notice that this introduces a regression with the following case:
function foo() {
let x
if (Math.random() > 0.5) {
x = 3;
} else {
x = 4;
}
// should be flagged as unnecessary
x!;
}I wonder if it's possible to get that case correct still? (it may or may not be feasible to prevent some false positives or negatives)
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actually - I think you can ignore this regression... This is most likely a symptom of #10334 / microsoft/TypeScript#60514
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@kirkwaiblinger
Thanks for review! 🙏
The regression also occurs in this simplified case:
function foo() {
let x;
x =4;
// should be flagged as unnecessary
x!;
}
This is most likely a symptom of #10334 / microsoft/TypeScript#60514
As you mentioned, it's not possible to fix that case for now.
Should I close this PR until that issue is resolved?
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Hmmm. I'm not sure which choice is the lesser of two evils here... fixing the bug at the cost of that rather undesirable-looking regression, or marking the bug as blocked. I'm gently leaning towards making this work as blocked unless we can find away to proceed while mitigating this regression 🤔 But then again if it was that important of a case, you'd think we might have a test case that caught it?
Looking for thoughts from @typescript-eslint/triage-team too.
PR Checklist
Overview
I have updated it so that isPossiblyUsedBeforeAssigned returns
truewhen the variable is not explicitly typed at the time of declaration