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=== tests/cases/conformance/types/spread/spreadObjectOrFalsy.ts ===
function f1<T>(a: T & undefined) {
>f1 : <T>(a: T & undefined) => any
>a : T & undefined
return { ...a }; // Error
>{ ...a } : any
>a : T & undefined
}
function f2<T>(a: T | T & undefined) {
>f2 : <T>(a: T | (T & undefined)) => T | (T & undefined)
>a : T | (T & undefined)
return { ...a };
>{ ...a } : T | (T & undefined)
>a : T | (T & undefined)
}
function f3<T extends undefined>(a: T) {
>f3 : <T extends undefined>(a: T) => any
>a : T
return { ...a }; // Error
>{ ...a } : any
>a : T
}
function f4<T extends undefined>(a: object | T) {
>f4 : <T extends undefined>(a: object | T) => {}
>a : object | T
return { ...a };
>{ ...a } : {}
>a : object | T
}
function f5<S, T extends undefined>(a: S | T) {
>f5 : <S, T extends undefined>(a: S | T) => S | T
>a : S | T
return { ...a };
>{ ...a } : S | T
>a : S | T
}
function f6<T extends object | undefined>(a: T) {
>f6 : <T extends object | undefined>(a: T) => T
>a : T
return { ...a };
>{ ...a } : T
>a : T
}
// Repro from #46976
function g1<T extends {}, A extends { z: (T | undefined) & T }>(a: A) {
>g1 : <T extends {}, A extends { z: (T | undefined) & T; }>(a: A) => T | (undefined & T)
>z : T | (undefined & T)
>a : A
const { z } = a;
>z : T | (undefined & T)
>a : A
return {
>{ ...z } : T | (undefined & T)
...z
>z : T | (undefined & T)
};
}
// Repro from #47028
interface DatafulFoo<T> {
data: T;
>data : T
}
class Foo<T extends string> {
>Foo : Foo<T>
data: T | undefined;
>data : T | undefined
bar() {
>bar : () => void
if (this.hasData()) {
>this.hasData() : boolean
>this.hasData : () => this is DatafulFoo<T>
>this : this
>hasData : () => this is DatafulFoo<T>
this.data.toLocaleLowerCase();
>this.data.toLocaleLowerCase() : string
>this.data.toLocaleLowerCase : (locales?: string | string[] | undefined) => string
>this.data : T | (undefined & T)
>this : this & DatafulFoo<T>
>data : T | (undefined & T)
>toLocaleLowerCase : (locales?: string | string[] | undefined) => string
}
}
hasData(): this is DatafulFoo<T> {
>hasData : () => this is DatafulFoo<T>
return true;
>true : true
}
}
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