forked from babel/babel
/
clone-deep.ts
32 lines (31 loc) 路 943 Bytes
/
clone-deep.ts
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//https://github.com/babel/babel/pull/14583#discussion_r882828856
function deepClone(value: any, cache: Map<any, any>): any {
if (value !== null) {
if (cache.has(value)) return cache.get(value);
let cloned: any;
if (Array.isArray(value)) {
cloned = new Array(value.length);
for (let i = 0; i < value.length; i++) {
cloned[i] =
typeof value[i] !== "object" ? value[i] : deepClone(value[i], cache);
}
} else {
cloned = {};
const keys = Object.keys(value);
for (let i = 0; i < keys.length; i++) {
const key = keys[i];
cloned[key] =
typeof value[key] !== "object"
? value[key]
: deepClone(value[key], cache);
}
}
cache.set(value, cloned);
return cloned;
}
return value;
}
export default function <T>(value: T): T {
if (typeof value !== "object") return value;
return deepClone(value, new Map());
}