b080aa9440
* Fix #16778 - use previous type to check discriminable type and not declared type * Rename prevType -> computedType
36 lines
549 B
TypeScript
36 lines
549 B
TypeScript
enum Kind {
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A,
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B,
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}
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interface Base {
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kind: Kind;
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}
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interface A extends Base {
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kind: Kind.A;
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yar: any;
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}
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interface B extends Base {
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kind: Kind.B;
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gar: any;
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}
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type Both = A | B;
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function isBoth(x: Base): x is Both {
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return true;
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}
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let foo: Base = undefined;
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if (isBoth(foo)) {
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switch (foo.kind) {
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case Kind.A:
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const myA: A = foo; // Should not be an error
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break;
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case Kind.B:
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const myB: B = foo;
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break;
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}
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}
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