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1import Diff from './base.js';2import { tokenize } from './line.js';3class JsonDiff extends Diff {4    constructor() {5        super(...arguments);6        this.tokenize = tokenize;7    }8    get useLongestToken() {9        // Discriminate between two lines of pretty-printed, serialized JSON where one of them has a10        // dangling comma and the other doesn't. Turns out including the dangling comma yields the nicest output:11        return true;12    }13    castInput(value, options) {14        const { undefinedReplacement, stringifyReplacer = (k, v) => typeof v === 'undefined' ? undefinedReplacement : v } = options;15        return typeof value === 'string' ? value : JSON.stringify(canonicalize(value, null, null, stringifyReplacer), null, '  ');16    }17    equals(left, right, options) {18        return super.equals(left.replace(/,([\r\n])/g, '$1'), right.replace(/,([\r\n])/g, '$1'), options);19    }20}21export const jsonDiff = new JsonDiff();22export function diffJson(oldStr, newStr, options) {23    return jsonDiff.diff(oldStr, newStr, options);24}25// This function handles the presence of circular references by bailing out when encountering an26// object that is already on the "stack" of items being processed. Accepts an optional replacer27export function canonicalize(obj, stack, replacementStack, replacer, key) {28    stack = stack || [];29    replacementStack = replacementStack || [];30    if (replacer) {31        obj = replacer(key === undefined ? '' : key, obj);32    }33    let i;34    for (i = 0; i < stack.length; i += 1) {35        if (stack[i] === obj) {36            return replacementStack[i];37        }38    }39    let canonicalizedObj;40    if ('[object Array]' === Object.prototype.toString.call(obj)) {41        stack.push(obj);42        canonicalizedObj = new Array(obj.length);43        replacementStack.push(canonicalizedObj);44        for (i = 0; i < obj.length; i += 1) {45            canonicalizedObj[i] = canonicalize(obj[i], stack, replacementStack, replacer, String(i));46        }47        stack.pop();48        replacementStack.pop();49        return canonicalizedObj;50    }51    if (obj && obj.toJSON) {52        obj = obj.toJSON();53    }54    if (typeof obj === 'object' && obj !== null) {55        stack.push(obj);56        canonicalizedObj = {};57        replacementStack.push(canonicalizedObj);58        const sortedKeys = [];59        let key;60        for (key in obj) {61            /* istanbul ignore else */62            if (Object.prototype.hasOwnProperty.call(obj, key)) {63                sortedKeys.push(key);64            }65        }66        sortedKeys.sort();67        for (i = 0; i < sortedKeys.length; i += 1) {68            key = sortedKeys[i];69            canonicalizedObj[key] = canonicalize(obj[key], stack, replacementStack, replacer, key);70        }71        stack.pop();72        replacementStack.pop();73    }74    else {75        canonicalizedObj = obj;76    }77    return canonicalizedObj;78}79