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tests/cases/conformance/types/spread/spreadObjectOrFalsy.ts(2,14): error TS2698: Spread types may only be created from object types.
tests/cases/conformance/types/spread/spreadObjectOrFalsy.ts(10,14): error TS2698: Spread types may only be created from object types.
==== tests/cases/conformance/types/spread/spreadObjectOrFalsy.ts (2 errors) ====
function f1<T>(a: T & undefined) {
return { ...a }; // Error
~~~~
!!! error TS2698: Spread types may only be created from object types.
}
function f2<T>(a: T | T & undefined) {
return { ...a };
}
function f3<T extends undefined>(a: T) {
return { ...a }; // Error
~~~~
!!! error TS2698: Spread types may only be created from object types.
}
function f4<T extends undefined>(a: object | T) {
return { ...a };
}
function f5<S, T extends undefined>(a: S | T) {
return { ...a };
}
function f6<T extends object | undefined>(a: T) {
return { ...a };
}
// Repro from #46976
function g1<T extends {}, A extends { z: (T | undefined) & T }>(a: A) {
const { z } = a;
return {
...z
};
}
// Repro from #47028
interface DatafulFoo<T> {
data: T;
}
class Foo<T extends string> {
data: T | undefined;
bar() {
if (this.hasData()) {
this.data.toLocaleLowerCase();
}
}
hasData(): this is DatafulFoo<T> {
return true;
}
}
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