612c92d603
* Track source and target relationship stack depth seperately, only increase on change in value * Add baselines for test from #43485 * Bail on unwrapping conditional constraints on the source side when the source conditional is already known to be spooling out of control * More usage of isDeeplyNestedType to block _specifically_ conditional recursion on only one side * Negative cases of getNarrowedType that match the exact type should be filtered out, even when generic * Add test and fix for #44404 * Swap to manually specifying left and right recursion * Rename Left -> Source, Right -> Target Co-authored-by: Andrew Branch <andrew@wheream.io>
45 lines
1.6 KiB
Plaintext
45 lines
1.6 KiB
Plaintext
=== tests/cases/compiler/genericCapturingFunctionNarrowing.ts ===
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function needsToNarrowTheType<First extends { foo: string }, Second extends { bar: string }, SubFirst extends First, SubFirstMore extends First & {other: string}>(thing: First | SubFirst | SubFirstMore | Second) {
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>needsToNarrowTheType : <First extends { foo: string; }, Second extends { bar: string; }, SubFirst extends First, SubFirstMore extends First & { other: string; }>(thing: First | SubFirst | SubFirstMore | Second) => void
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>foo : string
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>bar : string
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>other : string
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>thing : First | Second | SubFirst | SubFirstMore
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if (hasAFoo(thing)) {
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>hasAFoo(thing) : boolean
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>hasAFoo : (value: First | Second) => value is First
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>thing : First | Second | SubFirst | SubFirstMore
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console.log(thing.foo);
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>console.log(thing.foo) : void
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>console.log : (...data: any[]) => void
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>console : Console
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>log : (...data: any[]) => void
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>thing.foo : string
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>thing : First | SubFirst | SubFirstMore
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>foo : string
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}
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else {
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// I would expect this to work because the type should be narrowed in this branch to `Second`
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console.log(thing.bar); // Error: Property 'bar' does not exist on type 'First | Second'.
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>console.log(thing.bar) : void
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>console.log : (...data: any[]) => void
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>console : Console
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>log : (...data: any[]) => void
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>thing.bar : string
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>thing : Second
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>bar : string
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}
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function hasAFoo(value: First | Second): value is First {
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>hasAFoo : (value: First | Second) => value is First
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>value : First | Second
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return "foo" in value;
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>"foo" in value : boolean
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>"foo" : "foo"
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>value : First | Second
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}
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}
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