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//// [objectSpreadStrictNull.ts]
function f(
definiteBoolean: { sn: boolean },
definiteString: { sn: string },
optionalString: { sn?: string },
optionalNumber: { sn?: number },
undefinedString: { sn: string | undefined },
undefinedNumber: { sn: number | undefined }) {
// optional
let optionalUnionStops: { sn: string | number } = { ...definiteBoolean, ...definiteString, ...optionalNumber };
let optionalUnionDuplicates: { sn: string | number } = { ...definiteBoolean, ...definiteString, ...optionalString, ...optionalNumber };
let allOptional: { sn?: string | number } = { ...optionalString, ...optionalNumber };
// undefined
let undefinedUnionStops: { sn: string | number } = { ...definiteBoolean, ...definiteString, ...undefinedNumber };
let undefinedUnionDuplicates: { sn: string | number } = { ...definiteBoolean, ...definiteString, ...undefinedString, ...undefinedNumber };
let allUndefined: { sn: string | number | undefined } = { ...undefinedString, ...undefinedNumber };
let undefinedWithOptionalContinues: { sn: string | number | boolean } = { ...definiteBoolean, ...undefinedString, ...optionalNumber };
}
type Movie = {
title: string;
yearReleased: number;
}
const m = { title: "The Matrix", yearReleased: 1999 };
// should error here because title: undefined is not assignable to string
const x: Movie = { ...m, title: undefined };
interface Fields {
foo: number;
bar: string;
}
interface NearlyPartialFields {
foo: number | undefined;
bar: string | undefined;
}
function g(fields: Fields, partialFields: Partial<Fields>, nearlyPartialFields: NearlyPartialFields) {
// ok, undefined is stripped from optional properties when spread
fields = { ...fields, ...partialFields };
// error: not optional, undefined remains
fields = { ...fields, ...nearlyPartialFields };
}
//// [objectSpreadStrictNull.js]
var __assign = (this && this.__assign) || function () {
__assign = Object.assign || function(t) {
for (var s, i = 1, n = arguments.length; i < n; i++) {
s = arguments[i];
for (var p in s) if (Object.prototype.hasOwnProperty.call(s, p))
t[p] = s[p];
}
return t;
};
return __assign.apply(this, arguments);
};
function f(definiteBoolean, definiteString, optionalString, optionalNumber, undefinedString, undefinedNumber) {
// optional
var optionalUnionStops = __assign({}, definiteBoolean, definiteString, optionalNumber);
var optionalUnionDuplicates = __assign({}, definiteBoolean, definiteString, optionalString, optionalNumber);
var allOptional = __assign({}, optionalString, optionalNumber);
// undefined
var undefinedUnionStops = __assign({}, definiteBoolean, definiteString, undefinedNumber);
var undefinedUnionDuplicates = __assign({}, definiteBoolean, definiteString, undefinedString, undefinedNumber);
var allUndefined = __assign({}, undefinedString, undefinedNumber);
var undefinedWithOptionalContinues = __assign({}, definiteBoolean, undefinedString, optionalNumber);
}
var m = { title: "The Matrix", yearReleased: 1999 };
// should error here because title: undefined is not assignable to string
var x = __assign({}, m, { title: undefined });
function g(fields, partialFields, nearlyPartialFields) {
// ok, undefined is stripped from optional properties when spread
fields = __assign({}, fields, partialFields);
// error: not optional, undefined remains
fields = __assign({}, fields, nearlyPartialFields);
}
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