LendAndRegret/node_modules/es-toolkit/dist/compat/object/clone.mjs
2026-05-02 17:27:43 +08:00

161 lines
4.9 KiB
JavaScript

import { isPrimitive } from '../../predicate/isPrimitive.mjs';
import { getTag } from '../_internal/getTag.mjs';
import { arrayBufferTag, dataViewTag, booleanTag, numberTag, stringTag, dateTag, regexpTag, symbolTag, mapTag, setTag, argumentsTag, uint32ArrayTag, uint16ArrayTag, uint8ClampedArrayTag, uint8ArrayTag, objectTag, int32ArrayTag, int16ArrayTag, int8ArrayTag, float64ArrayTag, float32ArrayTag, arrayTag } from '../_internal/tags.mjs';
import { isArray } from '../predicate/isArray.mjs';
import { isTypedArray } from '../predicate/isTypedArray.mjs';
function clone(obj) {
if (isPrimitive(obj)) {
return obj;
}
const tag = getTag(obj);
if (!isCloneableObject(obj)) {
return {};
}
if (isArray(obj)) {
const result = Array.from(obj);
if (obj.length > 0 && typeof obj[0] === 'string' && Object.hasOwn(obj, 'index')) {
result.index = obj.index;
result.input = obj.input;
}
return result;
}
if (isTypedArray(obj)) {
const typedArray = obj;
const Ctor = typedArray.constructor;
return new Ctor(typedArray.buffer, typedArray.byteOffset, typedArray.length);
}
if (tag === arrayBufferTag) {
return new ArrayBuffer(obj.byteLength);
}
if (tag === dataViewTag) {
const dataView = obj;
const buffer = dataView.buffer;
const byteOffset = dataView.byteOffset;
const byteLength = dataView.byteLength;
const clonedBuffer = new ArrayBuffer(byteLength);
const srcView = new Uint8Array(buffer, byteOffset, byteLength);
const destView = new Uint8Array(clonedBuffer);
destView.set(srcView);
return new DataView(clonedBuffer);
}
if (tag === booleanTag || tag === numberTag || tag === stringTag) {
const Ctor = obj.constructor;
const clone = new Ctor(obj.valueOf());
if (tag === stringTag) {
cloneStringObjectProperties(clone, obj);
}
else {
copyOwnProperties(clone, obj);
}
return clone;
}
if (tag === dateTag) {
return new Date(Number(obj));
}
if (tag === regexpTag) {
const regExp = obj;
const clone = new RegExp(regExp.source, regExp.flags);
clone.lastIndex = regExp.lastIndex;
return clone;
}
if (tag === symbolTag) {
return Object(Symbol.prototype.valueOf.call(obj));
}
if (tag === mapTag) {
const map = obj;
const result = new Map();
map.forEach((obj, key) => {
result.set(key, obj);
});
return result;
}
if (tag === setTag) {
const set = obj;
const result = new Set();
set.forEach(obj => {
result.add(obj);
});
return result;
}
if (tag === argumentsTag) {
const args = obj;
const result = {};
copyOwnProperties(result, args);
result.length = args.length;
result[Symbol.iterator] = args[Symbol.iterator];
return result;
}
const result = {};
copyPrototype(result, obj);
copyOwnProperties(result, obj);
copySymbolProperties(result, obj);
return result;
}
function isCloneableObject(object) {
switch (getTag(object)) {
case argumentsTag:
case arrayTag:
case arrayBufferTag:
case dataViewTag:
case booleanTag:
case dateTag:
case float32ArrayTag:
case float64ArrayTag:
case int8ArrayTag:
case int16ArrayTag:
case int32ArrayTag:
case mapTag:
case numberTag:
case objectTag:
case regexpTag:
case setTag:
case stringTag:
case symbolTag:
case uint8ArrayTag:
case uint8ClampedArrayTag:
case uint16ArrayTag:
case uint32ArrayTag: {
return true;
}
default: {
return false;
}
}
}
function copyOwnProperties(target, source) {
for (const key in source) {
if (Object.hasOwn(source, key)) {
target[key] = source[key];
}
}
}
function copySymbolProperties(target, source) {
const symbols = Object.getOwnPropertySymbols(source);
for (let i = 0; i < symbols.length; i++) {
const symbol = symbols[i];
if (Object.prototype.propertyIsEnumerable.call(source, symbol)) {
target[symbol] = source[symbol];
}
}
}
function cloneStringObjectProperties(target, source) {
const stringLength = source.valueOf().length;
for (const key in source) {
if (Object.hasOwn(source, key) && (Number.isNaN(Number(key)) || Number(key) >= stringLength)) {
target[key] = source[key];
}
}
}
function copyPrototype(target, source) {
const proto = Object.getPrototypeOf(source);
if (proto !== null) {
const Ctor = source.constructor;
if (typeof Ctor === 'function') {
Object.setPrototypeOf(target, proto);
}
}
}
export { clone };