62 lines
1.1 KiB
TypeScript
62 lines
1.1 KiB
TypeScript
// @strictNullChecks: true
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var a: object
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declare var b: object | null
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declare var c: object | undefined
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declare var d: object | null | undefined
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var e: object | null
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a.toString; // error
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a = undefined; // error
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a = null; // error
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a = b; // error
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a = c; // error
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a = d; // error
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e = a; // ok
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a = e; // ok
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if (typeof b !== 'object') {
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b.toString(); // error, never
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}
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if (typeof b === 'object') {
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a = b; // error, b is not narrowed
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}
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if (typeof d === 'object') {
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b = d; // ok
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d.toString(); // error, object | null
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} else {
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d.toString(); // error, undefined
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}
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if (d == null) {
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d.toString(); // error, undefined | null
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} else {
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d.toString(); // object
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}
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if (d === null) {
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d.toString(); // error, null
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} else {
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d.toString(); // error, object | undefined
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}
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if (typeof d === 'undefined') {
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d.toString(); // error, undefined
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} else {
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d.toString(); // error, object | null
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}
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interface Proxy<T extends object> {}
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var x: Proxy<number>; // error
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var y: Proxy<null>; // error
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var z: Proxy<undefined>; // error
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interface Blah {
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foo: number;
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}
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var u: Proxy<Blah>; // ok
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