ut2/lib/internals/isEqualDeep.js

一个现代 JavaScript 实用工具库。[点击查看在线文档]。

'use strict';

var allKeys = require('../allKeys.js');
var eq = require('../eq.js');
var getTagWithBugfix = require('./getTagWithBugfix.js');
var native = require('./native.js');
var isBuffer = require('../isBuffer.js');
var isFunction = require('../isFunction.js');
var isNil = require('../isNil.js');
var isObjectLike = require('../isObjectLike.js');
var isTypedArray = require('../isTypedArray.js');
var orderBy = require('../orderBy.js');

var symbolValueOf = native.symbolProto ? native.symbolProto.valueOf : native.nativeUndefined;
function mapToArray(map) {
    var result = [];
    map.forEach(function (value, key) {
        result.push([key, value]);
    });
    return orderBy(result, [0, 1]);
}
function setToArray(set) {
    var result = [];
    set.forEach(function (value) {
        result.push(value);
    });
    return orderBy(result);
}
function argToArray(arg) {
    return native.arrayProtoSlice.call(arg);
}
function toBufferView(bufferSource) {
    return new Uint8Array(bufferSource.buffer || bufferSource, bufferSource.byteOffset || 0, bufferSource.byteLength);
}
function isDomNode(obj) {
    return isObjectLike(obj) && typeof obj.nodeType === 'number' && typeof obj.nodeName === 'string' && typeof obj.isEqualNode === 'function';
}
function isEqualDeep(value, other, customizer, strictCheck, valueStack, otherStack) {
    if (eq(value, other, strictCheck)) {
        return true;
    }
    var valType = typeof value;
    var othType = typeof other;
    if (strictCheck && valType !== othType) {
        return false;
    }
    if (isNil(value) || isNil(other) || (valType !== 'object' && othType !== 'object')) {
        return false;
    }
    var tag = getTagWithBugfix(value);
    if (tag !== getTagWithBugfix(other)) {
        return false;
    }
    var convert;
    switch (tag) {
        case native.numberTag:
            return eq(+value, +other, strictCheck);
        case native.booleanTag:
        case native.dateTag:
            return strictCheck ? +value === +other : eq(+value, +other);
        case native.stringTag:
        case native.regExpTag:
            return '' + value === '' + other;
        case native.symbolTag:
            return symbolValueOf ? symbolValueOf.call(value) === symbolValueOf.call(other) : false;
        case native.errorTag:
            return value.name === other.name && value.message === other.message;
        case native.dataViewTag:
        case native.arrayBufferTag:
            if (value.byteLength !== other.byteLength || (value.byteOffset && value.byteOffset !== other.byteOffset)) {
                return false;
            }
            convert = toBufferView;
            break;
        case native.mapTag:
            convert = mapToArray;
            break;
        case native.setTag:
            convert = setToArray;
            break;
        case native.argumentsTag:
            convert = argToArray;
            break;
    }
    if (convert) {
        return isEqualDeep(convert(value), convert(other), customizer, strictCheck, valueStack, otherStack);
    }
    if (isDomNode(value) && isDomNode(other)) {
        return value.isEqualNode(other);
    }
    var areArrays = tag === native.arrayTag;
    if (!areArrays && isTypedArray(value)) {
        if (value.byteLength !== other.byteLength) {
            return false;
        }
        if (value.buffer === other.buffer && value.byteOffset === other.byteOffset) {
            return true;
        }
        areArrays = true;
    }
    if (isBuffer(value)) {
        if (!isBuffer(other)) {
            return false;
        }
        areArrays = true;
    }
    valueStack = valueStack || [];
    otherStack = otherStack || [];
    var length = valueStack.length;
    while (length--) {
        if (valueStack[length] === value) {
            return otherStack[length] === other;
        }
    }
    valueStack.push(value);
    otherStack.push(other);
    var result = true;
    var hasCustomizer = typeof customizer === 'function';
    if (areArrays) {
        length = value.length;
        if (length !== other.length) {
            return false;
        }
        while (length--) {
            if (hasCustomizer) {
                var compared = customizer(value[length], other[length], length, value, other, valueStack, otherStack);
                if (compared !== native.nativeUndefined) {
                    if (!compared) {
                        return false;
                    }
                    continue;
                }
            }
            if (!isEqualDeep(value[length], other[length], customizer, strictCheck, valueStack, otherStack)) {
                return false;
            }
        }
    }
    else if (tag === native.objectTag) {
        var keys = allKeys(value);
        length = keys.length;
        if (allKeys(other).length !== length) {
            return false;
        }
        var skipCtor = false;
        while (length--) {
            var key = keys[length];
            if (hasCustomizer) {
                var compared = customizer(value[key], other[key], key, value, other, valueStack, otherStack);
                if (compared !== native.nativeUndefined) {
                    if (!compared) {
                        return false;
                    }
                    continue;
                }
            }
            if (!(native.objectProtoHasOwnProperty.call(other, key) && isEqualDeep(value[key], other[key], customizer, strictCheck, valueStack, otherStack))) {
                return false;
            }
            if (!skipCtor && key === 'constructor') {
                skipCtor = true;
            }
        }
        if (!skipCtor) {
            var valCtor = value.constructor;
            var othCtor = other.constructor;
            if (valCtor !== othCtor && !(isFunction(valCtor) && valCtor instanceof valCtor && isFunction(othCtor) && othCtor instanceof othCtor) && 'constructor' in value && 'constructor' in other) {
                return false;
            }
        }
    }
    else {
        result = false;
    }
    valueStack.pop();
    otherStack.pop();
    return result;
}

module.exports = isEqualDeep;