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=== tests/cases/compiler/discriminantsAndTypePredicates.ts ===
// Repro from #10145
interface A { type: 'A' }
>type : "A"
interface B { type: 'B' }
>type : "B"
function isA(x: A | B): x is A { return x.type === 'A'; }
>isA : (x: A | B) => x is A
>x : A | B
>x.type === 'A' : boolean
>x.type : "A" | "B"
>x : A | B
>type : "A" | "B"
>'A' : "A"
function isB(x: A | B): x is B { return x.type === 'B'; }
>isB : (x: A | B) => x is B
>x : A | B
>x.type === 'B' : boolean
>x.type : "A" | "B"
>x : A | B
>type : "A" | "B"
>'B' : "B"
function foo1(x: A | B): any {
>foo1 : (x: A | B) => any
>x : A | B
x; // A | B
>x : A | B
if (isA(x)) {
>isA(x) : boolean
>isA : (x: A | B) => x is A
>x : A | B
return x; // A
>x : A
}
x; // B
>x : B
if (isB(x)) {
>isB(x) : boolean
>isB : (x: A | B) => x is B
>x : B
return x; // B
>x : B
}
x; // never
>x : never
}
function foo2(x: A | B): any {
>foo2 : (x: A | B) => any
>x : A | B
x; // A | B
>x : A | B
if (x.type === 'A') {
>x.type === 'A' : boolean
>x.type : "A" | "B"
>x : A | B
>type : "A" | "B"
>'A' : "A"
return x; // A
>x : A
}
x; // B
>x : B
if (x.type === 'B') {
>x.type === 'B' : boolean
>x.type : "B"
>x : B
>type : "B"
>'B' : "B"
return x; // B
>x : B
}
x; // never
>x : never
}
|
