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// ==UserScript==
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// @name         AjaxHooker
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// @author       Yuusei
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// @version      1.4.3
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// ==/UserScript==
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var ajaxHooker = function() {
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    'use strict';
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    const version = '1.4.3';
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    const hookInst = {
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        hookFns: [],
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        filters: []
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    };
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    const win = window.unsafeWindow || document.defaultView || window;
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    let winAh = win.__ajaxHooker;
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    const resProto = win.Response.prototype;
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    const xhrResponses = ['response', 'responseText', 'responseXML'];
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    const fetchResponses = ['arrayBuffer', 'blob', 'formData', 'json', 'text'];
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    const fetchInitProps = ['method', 'headers', 'body', 'mode', 'credentials', 'cache', 'redirect',
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        'referrer', 'referrerPolicy', 'integrity', 'keepalive', 'signal', 'priority'];
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    const xhrAsyncEvents = ['readystatechange', 'load', 'loadend'];
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    const getType = ({}).toString.call.bind(({}).toString);
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    const getDescriptor = Object.getOwnPropertyDescriptor.bind(Object);
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    const emptyFn = () => {};
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    const errorFn = e => console.error(e);
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    function isThenable(obj) {
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        return obj && ['object', 'function'].includes(typeof obj) && typeof obj.then === 'function';
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    }
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    function catchError(fn, ...args) {
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        try {
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            const result = fn(...args);
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            if (isThenable(result)) return result.then(null, errorFn);
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            return result;
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        } catch (err) {
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            console.error(err);
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        }
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    }
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    function defineProp(obj, prop, getter, setter) {
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        Object.defineProperty(obj, prop, {
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            configurable: true,
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            enumerable: true,
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            get: getter,
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            set: setter
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        });
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    }
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    function readonly(obj, prop, value = obj[prop]) {
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        defineProp(obj, prop, () => value, emptyFn);
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    }
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    function writable(obj, prop, value = obj[prop]) {
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        Object.defineProperty(obj, prop, {
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            configurable: true,
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            enumerable: true,
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            writable: true,
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            value: value
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        });
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    }
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    function parseHeaders(obj) {
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        const headers = {};
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        switch (getType(obj)) {
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            case '[object String]':
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                for (const line of obj.trim().split(/[\r\n]+/)) {
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                    const [header, value] = line.split(/\s*:\s*/);
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                    if (!header) break;
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                    const lheader = header.toLowerCase();
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                    headers[lheader] = lheader in headers ? `${headers[lheader]}, ${value}` : value;
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                }
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                break;
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            case '[object Headers]':
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                for (const [key, val] of obj) {
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                    headers[key] = val;
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                }
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                break;
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            case '[object Object]':
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                return {...obj};
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        }
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        return headers;
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    }
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    function stopImmediatePropagation() {
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        this.ajaxHooker_isStopped = true;
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    }
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    class SyncThenable {
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        then(fn) {
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            fn && fn();
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            return new SyncThenable();
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        }
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    }
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    class AHRequest {
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        constructor(request) {
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            this.request = request;
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            this.requestClone = {...this.request};
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        }
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        shouldFilter(filters) {
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            const {type, url, method, async} = this.request;
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            return filters.length && !filters.find(obj => {
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                switch (true) {
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                    case obj.type && obj.type !== type:
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                    case getType(obj.url) === '[object String]' && !url.includes(obj.url):
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                    case getType(obj.url) === '[object RegExp]' && !obj.url.test(url):
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                    case obj.method && obj.method.toUpperCase() !== method.toUpperCase():
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                    case 'async' in obj && obj.async !== async:
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                        return false;
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                }
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                return true;
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            });
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        }
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        waitForRequestKeys() {
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            const requestKeys = ['url', 'method', 'abort', 'headers', 'data'];
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            if (!this.request.async) {
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                win.__ajaxHooker.hookInsts.forEach(({hookFns, filters}) => {
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                    if (this.shouldFilter(filters)) return;
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                    hookFns.forEach(fn => {
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                        if (getType(fn) === '[object Function]') catchError(fn, this.request);
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                    });
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                    requestKeys.forEach(key => {
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                        if (isThenable(this.request[key])) this.request[key] = this.requestClone[key];
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                    });
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                });
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                return new SyncThenable();
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            }
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            const promises = [];
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            win.__ajaxHooker.hookInsts.forEach(({hookFns, filters}) => {
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                if (this.shouldFilter(filters)) return;
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                promises.push(Promise.all(hookFns.map(fn => catchError(fn, this.request))).then(() => 
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                    Promise.all(requestKeys.map(key => Promise.resolve(this.request[key]).then(
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                        val => this.request[key] = val,
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                        () => this.request[key] = this.requestClone[key]
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                    )))
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                ));
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            });
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            return Promise.all(promises);
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        }
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        waitForResponseKeys(response) {
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            const responseKeys = this.request.type === 'xhr' ? xhrResponses : fetchResponses;
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            if (!this.request.async) {
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                if (getType(this.request.response) === '[object Function]') {
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                    catchError(this.request.response, response);
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                    responseKeys.forEach(key => {
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                        if ('get' in getDescriptor(response, key) || isThenable(response[key])) {
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                            delete response[key];
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                        }
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                    });
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                }
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                return new SyncThenable();
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            }
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            return Promise.resolve(catchError(this.request.response, response)).then(() =>
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                Promise.all(responseKeys.map(key => {
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                    const descriptor = getDescriptor(response, key);
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                    if (descriptor && 'value' in descriptor) {
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                        return Promise.resolve(descriptor.value).then(
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                            val => response[key] = val,
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                            () => delete response[key]
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                        );
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                    } else {
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                        delete response[key];
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                    }
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                }))
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            );
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        }
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    }
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    const proxyHandler = {
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        get(target, prop) {
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            const descriptor = getDescriptor(target, prop);
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            if (descriptor && !descriptor.configurable && !descriptor.writable && !descriptor.get) return target[prop];
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            const ah = target.__ajaxHooker;
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            if (ah && ah.proxyProps) {
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                if (prop in ah.proxyProps) {
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                    const pDescriptor = ah.proxyProps[prop];
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                    if ('get' in pDescriptor) return pDescriptor.get();
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                    if (typeof pDescriptor.value === 'function') return pDescriptor.value.bind(ah);
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                    return pDescriptor.value;
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                }
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                if (typeof target[prop] === 'function') return target[prop].bind(target);
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            }
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            return target[prop];
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        },
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        set(target, prop, value) {
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            const descriptor = getDescriptor(target, prop);
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            if (descriptor && !descriptor.configurable && !descriptor.writable && !descriptor.set) return true;
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            const ah = target.__ajaxHooker;
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            if (ah && ah.proxyProps && prop in ah.proxyProps) {
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                const pDescriptor = ah.proxyProps[prop];
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                pDescriptor.set ? pDescriptor.set(value) : (pDescriptor.value = value);
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            } else {
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                target[prop] = value;
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            }
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            return true;
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        }
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    };
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    class XhrHooker {
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        constructor(xhr) {
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            const ah = this;
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            Object.assign(ah, {
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                originalXhr: xhr,
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                proxyXhr: new Proxy(xhr, proxyHandler),
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                resThenable: new SyncThenable(),
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                proxyProps: {},
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                proxyEvents: {}
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            });
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            xhr.addEventListener('readystatechange', e => {
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                if (ah.proxyXhr.readyState === 4 && ah.request && typeof ah.request.response === 'function') {
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                    const response = {
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                        finalUrl: ah.proxyXhr.responseURL,
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                        status: ah.proxyXhr.status,
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                        responseHeaders: parseHeaders(ah.proxyXhr.getAllResponseHeaders())
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                    };
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                    const tempValues = {};
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                    for (const key of xhrResponses) {
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                        try {
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                            tempValues[key] = ah.originalXhr[key];
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                        } catch (err) {}
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                        defineProp(response, key, () => {
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                            return response[key] = tempValues[key];
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                        }, val => {
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                            delete response[key];
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                            response[key] = val;
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                        });
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                    }
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                    ah.resThenable = new AHRequest(ah.request).waitForResponseKeys(response).then(() => {
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                        for (const key of xhrResponses) {
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                            ah.proxyProps[key] = {get: () => {
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                                if (!(key in response)) response[key] = tempValues[key];
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                                return response[key];
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                            }};
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                        }
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                    });
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                }
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                ah.dispatchEvent(e);
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            });
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            xhr.addEventListener('load', e => ah.dispatchEvent(e));
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            xhr.addEventListener('loadend', e => ah.dispatchEvent(e));
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            for (const evt of xhrAsyncEvents) {
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                const onEvt = 'on' + evt;
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                ah.proxyProps[onEvt] = {
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                    get: () => ah.proxyEvents[onEvt] || null,
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                    set: val => ah.addEvent(onEvt, val)
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                };
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            }
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            for (const method of ['setRequestHeader', 'addEventListener', 'removeEventListener', 'open', 'send']) {
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                ah.proxyProps[method] = {value: ah[method]};
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            }
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        }
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        toJSON() {} // Converting circular structure to JSON
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        addEvent(type, event) {
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            if (type.startsWith('on')) {
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                this.proxyEvents[type] = typeof event === 'function' ? event : null;
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            } else {
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                if (typeof event === 'object' && event !== null) event = event.handleEvent;
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                if (typeof event !== 'function') return;
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                this.proxyEvents[type] = this.proxyEvents[type] || new Set();
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                this.proxyEvents[type].add(event);
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            }
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        }
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        removeEvent(type, event) {
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            if (type.startsWith('on')) {
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                this.proxyEvents[type] = null;
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            } else {
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                if (typeof event === 'object' && event !== null) event = event.handleEvent;
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                this.proxyEvents[type] && this.proxyEvents[type].delete(event);
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            }
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        }
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        dispatchEvent(e) {
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            e.stopImmediatePropagation = stopImmediatePropagation;
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            defineProp(e, 'target', () => this.proxyXhr);
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            defineProp(e, 'currentTarget', () => this.proxyXhr);
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            this.proxyEvents[e.type] && this.proxyEvents[e.type].forEach(fn => {
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                this.resThenable.then(() => !e.ajaxHooker_isStopped && fn.call(this.proxyXhr, e));
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            });
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            if (e.ajaxHooker_isStopped) return;
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            const onEvent = this.proxyEvents['on' + e.type];
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            onEvent && this.resThenable.then(onEvent.bind(this.proxyXhr, e));
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        }
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        setRequestHeader(header, value) {
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            this.originalXhr.setRequestHeader(header, value);
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            if (!this.request) return;
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            const headers = this.request.headers;
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            headers[header] = header in headers ? `${headers[header]}, ${value}` : value;
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        }
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        addEventListener(...args) {
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            if (xhrAsyncEvents.includes(args[0])) {
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                this.addEvent(args[0], args[1]);
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            } else {
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                this.originalXhr.addEventListener(...args);
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            }
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        }
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        removeEventListener(...args) {
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            if (xhrAsyncEvents.includes(args[0])) {
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                this.removeEvent(args[0], args[1]);
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            } else {
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                this.originalXhr.removeEventListener(...args);
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            }
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        }
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        open(method, url, async = true, ...args) {
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            this.request = {
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                type: 'xhr',
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                url: url.toString(),
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                method: method.toUpperCase(),
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                abort: false,
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                headers: {},
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                data: null,
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                response: null,
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                async: !!async
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            };
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            this.openArgs = args;
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            this.resThenable = new SyncThenable();
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            ['responseURL', 'readyState', 'status', 'statusText', ...xhrResponses].forEach(key => {
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                delete this.proxyProps[key];
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            });
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            return this.originalXhr.open(method, url, async, ...args);
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        }
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        send(data) {
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            const ah = this;
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            const xhr = ah.originalXhr;
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            const request = ah.request;
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            if (!request) return xhr.send(data);
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            request.data = data;
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            new AHRequest(request).waitForRequestKeys().then(() => {
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                if (request.abort) {
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                    if (typeof request.response === 'function') {
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                        Object.assign(ah.proxyProps, {
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                            responseURL: {value: request.url},
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                            readyState: {value: 4},
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                            status: {value: 200},
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                            statusText: {value: 'OK'}
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                        });
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                        xhrAsyncEvents.forEach(evt => xhr.dispatchEvent(new Event(evt)));
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                    }
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                } else {
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                    xhr.open(request.method, request.url, request.async, ...ah.openArgs);
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                    for (const header in request.headers) {
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                        xhr.setRequestHeader(header, request.headers[header]);
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                    }
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                    xhr.send(request.data);
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                }
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            });
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        }
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    }
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    function fakeXHR() {
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        const xhr = new winAh.realXHR();
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        if ('__ajaxHooker' in xhr) console.warn('检测到不同版本的ajaxHooker，可能发生冲突！');
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        xhr.__ajaxHooker = new XhrHooker(xhr);
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        return xhr.__ajaxHooker.proxyXhr;
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    }
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    fakeXHR.prototype = win.XMLHttpRequest.prototype;
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    Object.keys(win.XMLHttpRequest).forEach(key => fakeXHR[key] = win.XMLHttpRequest[key]);
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    function fakeFetch(url, options = {}) {
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        if (!url) return winAh.realFetch.call(win, url, options);
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        return new Promise(async (resolve, reject) => {
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            const init = {};
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            if (getType(url) === '[object Request]') {
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                for (const prop of fetchInitProps) init[prop] = url[prop];
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                if (url.body) init.body = await url.arrayBuffer();
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                url = url.url;
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            }
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            url = url.toString();
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            Object.assign(init, options);
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            init.method = init.method || 'GET';
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            init.headers = init.headers || {};
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            const request = {
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                type: 'fetch',
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                url: url,
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                method: init.method.toUpperCase(),
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                abort: false,
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                headers: parseHeaders(init.headers),
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                data: init.body,
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                response: null,
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                async: true
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            };
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            const req = new AHRequest(request);
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            await req.waitForRequestKeys();
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            if (request.abort) {
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                if (typeof request.response === 'function') {
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                    const response = {
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                        finalUrl: request.url,
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                        status: 200,
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                        responseHeaders: {}
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                    };
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                    await req.waitForResponseKeys(response);
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                    const key = fetchResponses.find(k => k in response);
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                    let val = response[key];
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                    if (key === 'json' && typeof val === 'object') {
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                        val = catchError(JSON.stringify.bind(JSON), val);
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                    }
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                    const res = new Response(val, {
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                        status: 200,
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                        statusText: 'OK'
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                    });
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                    defineProp(res, 'type', () => 'basic');
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                    defineProp(res, 'url', () => request.url);
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                    resolve(res);
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                } else {
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                    reject(new DOMException('aborted', 'AbortError'));
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                }
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                return;
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            }
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            init.method = request.method;
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            init.headers = request.headers;
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            init.body = request.data;
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            winAh.realFetch.call(win, request.url, init).then(res => {
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                if (typeof request.response === 'function') {
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                    const response = {
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                        finalUrl: res.url,
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                        status: res.status,
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                        responseHeaders: parseHeaders(res.headers)
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                    };
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                    fetchResponses.forEach(key => res[key] = function() {
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                        if (key in response) return Promise.resolve(response[key]);
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                        return resProto[key].call(this).then(val => {
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                            response[key] = val;
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                            return req.waitForResponseKeys(response).then(() => key in response ? response[key] : val);
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                        });
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                    });
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                }
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                resolve(res);
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            }, reject);
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        });
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    }
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    function fakeFetchClone() {
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        const descriptors = Object.getOwnPropertyDescriptors(this);
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        const res = winAh.realFetchClone.call(this);
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        Object.defineProperties(res, descriptors);
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        return res;
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    }
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    winAh = win.__ajaxHooker = winAh || {
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        version, fakeXHR, fakeFetch, fakeFetchClone,
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        realXHR: win.XMLHttpRequest,
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        realFetch: win.fetch,
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        realFetchClone: resProto.clone,
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        hookInsts: new Set()
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    };
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    if (winAh.version !== version) console.warn('A different version of AjaxHooker was detected, which may cause conflicts!');
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    win.XMLHttpRequest = winAh.fakeXHR;
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    win.fetch = winAh.fakeFetch;
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    resProto.clone = winAh.fakeFetchClone;
434
    winAh.hookInsts.add(hookInst);
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    return {
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        hook: fn => hookInst.hookFns.push(fn),
437
        filter: arr => {
438
            if (Array.isArray(arr)) hookInst.filters = arr;
439
        },
440
        protect: () => {
441
            readonly(win, 'XMLHttpRequest', winAh.fakeXHR);
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            readonly(win, 'fetch', winAh.fakeFetch);
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            readonly(resProto, 'clone', winAh.fakeFetchClone);
444
        },
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        unhook: () => {
446
            winAh.hookInsts.delete(hookInst);
447
            if (!winAh.hookInsts.size) {
448
                writable(win, 'XMLHttpRequest', winAh.realXHR);
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                writable(win, 'fetch', winAh.realFetch);
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                writable(resProto, 'clone', winAh.realFetchClone);
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                delete win.__ajaxHooker;
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            }
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        }
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    };
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    }();