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=== tests/cases/conformance/types/spread/objectSpreadStrictNull.ts ===
function f(
>f : (definiteBoolean: { sn: boolean;}, definiteString: { sn: string;}, optionalString: { sn?: string;}, optionalNumber: { sn?: number;}, undefinedString: { sn: string | undefined;}, undefinedNumber: { sn: number | undefined;}) => void
definiteBoolean: { sn: boolean },
>definiteBoolean : { sn: boolean; }
>sn : boolean
definiteString: { sn: string },
>definiteString : { sn: string; }
>sn : string
optionalString: { sn?: string },
>optionalString : { sn?: string | undefined; }
>sn : string | undefined
optionalNumber: { sn?: number },
>optionalNumber : { sn?: number | undefined; }
>sn : number | undefined
undefinedString: { sn: string | undefined },
>undefinedString : { sn: string | undefined; }
>sn : string | undefined
undefinedNumber: { sn: number | undefined }) {
>undefinedNumber : { sn: number | undefined; }
>sn : number | undefined
// optional
let optionalUnionStops: { sn: string | number } = { ...definiteBoolean, ...definiteString, ...optionalNumber };
>optionalUnionStops : { sn: string | number; }
>sn : string | number
>{ ...definiteBoolean, ...definiteString, ...optionalNumber } : { sn: string | number; }
>definiteBoolean : { sn: boolean; }
>definiteString : { sn: string; }
>optionalNumber : { sn?: number | undefined; }
let optionalUnionDuplicates: { sn: string | number } = { ...definiteBoolean, ...definiteString, ...optionalString, ...optionalNumber };
>optionalUnionDuplicates : { sn: string | number; }
>sn : string | number
>{ ...definiteBoolean, ...definiteString, ...optionalString, ...optionalNumber } : { sn: string | number; }
>definiteBoolean : { sn: boolean; }
>definiteString : { sn: string; }
>optionalString : { sn?: string | undefined; }
>optionalNumber : { sn?: number | undefined; }
let allOptional: { sn?: string | number } = { ...optionalString, ...optionalNumber };
>allOptional : { sn?: string | number | undefined; }
>sn : string | number | undefined
>{ ...optionalString, ...optionalNumber } : { sn?: string | number | undefined; }
>optionalString : { sn?: string | undefined; }
>optionalNumber : { sn?: number | undefined; }
// undefined
let undefinedUnionStops: { sn: string | number } = { ...definiteBoolean, ...definiteString, ...undefinedNumber };
>undefinedUnionStops : { sn: string | number; }
>sn : string | number
>{ ...definiteBoolean, ...definiteString, ...undefinedNumber } : { sn: number | undefined; }
>definiteBoolean : { sn: boolean; }
>definiteString : { sn: string; }
>undefinedNumber : { sn: number | undefined; }
let undefinedUnionDuplicates: { sn: string | number } = { ...definiteBoolean, ...definiteString, ...undefinedString, ...undefinedNumber };
>undefinedUnionDuplicates : { sn: string | number; }
>sn : string | number
>{ ...definiteBoolean, ...definiteString, ...undefinedString, ...undefinedNumber } : { sn: number | undefined; }
>definiteBoolean : { sn: boolean; }
>definiteString : { sn: string; }
>undefinedString : { sn: string | undefined; }
>undefinedNumber : { sn: number | undefined; }
let allUndefined: { sn: string | number | undefined } = { ...undefinedString, ...undefinedNumber };
>allUndefined : { sn: string | number | undefined; }
>sn : string | number | undefined
>{ ...undefinedString, ...undefinedNumber } : { sn: number | undefined; }
>undefinedString : { sn: string | undefined; }
>undefinedNumber : { sn: number | undefined; }
let undefinedWithOptionalContinues: { sn: string | number | boolean } = { ...definiteBoolean, ...undefinedString, ...optionalNumber };
>undefinedWithOptionalContinues : { sn: string | number | boolean; }
>sn : string | number | boolean
>{ ...definiteBoolean, ...undefinedString, ...optionalNumber } : { sn: string | number | undefined; }
>definiteBoolean : { sn: boolean; }
>undefinedString : { sn: string | undefined; }
>optionalNumber : { sn?: number | undefined; }
}
type Movie = {
>Movie : { title: string; yearReleased: number; }
title: string;
>title : string
yearReleased: number;
>yearReleased : number
}
const m = { title: "The Matrix", yearReleased: 1999 };
>m : { title: string; yearReleased: number; }
>{ title: "The Matrix", yearReleased: 1999 } : { title: string; yearReleased: number; }
>title : string
>"The Matrix" : "The Matrix"
>yearReleased : number
>1999 : 1999
// should error here because title: undefined is not assignable to string
const x: Movie = { ...m, title: undefined };
>x : Movie
>{ ...m, title: undefined } : { title: undefined; yearReleased: number; }
>m : { title: string; yearReleased: number; }
>title : undefined
>undefined : undefined
interface Fields {
foo: number;
>foo : number
bar: string;
>bar : string
}
interface NearlyPartialFields {
foo: number | undefined;
>foo : number | undefined
bar: string | undefined;
>bar : string | undefined
}
function g(fields: Fields, partialFields: Partial<Fields>, nearlyPartialFields: NearlyPartialFields) {
>g : (fields: Fields, partialFields: Partial<Fields>, nearlyPartialFields: NearlyPartialFields) => void
>fields : Fields
>partialFields : Partial<Fields>
>nearlyPartialFields : NearlyPartialFields
// ok, undefined is stripped from optional properties when spread
fields = { ...fields, ...partialFields };
>fields = { ...fields, ...partialFields } : { foo: number; bar: string; }
>fields : Fields
>{ ...fields, ...partialFields } : { foo: number; bar: string; }
>fields : Fields
>partialFields : Partial<Fields>
// error: not optional, undefined remains
fields = { ...fields, ...nearlyPartialFields };
>fields = { ...fields, ...nearlyPartialFields } : { foo: number | undefined; bar: string | undefined; }
>fields : Fields
>{ ...fields, ...nearlyPartialFields } : { foo: number | undefined; bar: string | undefined; }
>fields : Fields
>nearlyPartialFields : NearlyPartialFields
}
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