ultraviolet/client/native/function.js

import EventEmitter from "../events.js";
import HookEvent from "../hook.js";

class FunctionHook extends EventEmitter {
    constructor(ctx) {
        super();
        this.ctx = ctx;
        this.window = ctx.window;
        this.Function = this.window.Function;
        this.fnProto = this.Function.prototype;
        this.toString = this.fnProto.toString;
        this.fnStrings = ctx.fnStrings;
        this.call = this.fnProto.call;
        this.apply = this.fnProto.apply;
        this.bind = this.fnProto.bind;
    };
    overrideFunction() {
        this.ctx.override(this.window, 'Function', (target, that, args) => {
            if (!args.length) return target.apply(that, args);

            let script = args[args.length - 1];
            let fnArgs = [];

            for (let i = 0; i < args.length - 1; i++) {
                fnArgs.push(args[i]);
            };

            const event = new HookEvent({ script, args: fnArgs }, target, that);
            this.emit('function', event);

            if (event.intercepted) return event.returnValue;
            return event.target.call(event.that, ...event.data.args, event.data.script);
        }, true);
    };
    overrideToString() {
        this.ctx.override(this.fnProto, 'toString', (target, that) => {
            const event = new HookEvent({ fn: that }, target, that);
            this.emit('toString', event);

            if (event.intercepted) return event.returnValue;
            return event.target.call(event.data.fn);
        });
    };
};

export default FunctionHook;