xy-events/src/core/dispatchEvent.js

An events system for JavaScript

function exec(stack, thisArg, args) {
    const ss = stack.shift();
    if(!ss) {
        return Promise.resolve(true);
    }

    const { mode, listener } = ss;

    if (mode === 'async') {
        return Promise.resolve(Reflect.apply(listener, thisArg, args)).then(isBreak => isBreak === true ? Promise.resolve(false) : exec(stack, thisArg, args)).catch(() => Promise.resolve(false));
    }

    if(Reflect.apply(listener, thisArg, args) === true) {
        return Promise.resolve(false);
    }
    return exec(stack, thisArg, args);
}

function asyncExec(stack, thisArg, args) {
    const ss = stack.shift();
    if(!ss) {
        return Promise.resolve(true);
    }

    const { listener } = ss;

    return Promise.resolve(Reflect.apply(listener, thisArg, args)).then(isBreak => isBreak ? Promise.resolve(false) : exec(stack, thisArg, args)).catch(() => Promise.resolve(false));
}

export function asyncDispatchEvent(arg1) {
    let stack = [];
    let args = [];
    const listeners = this._listeners;

    if(typeof arg1 === 'string') {
        stack = listeners[arg1];
        args = Array.prototype.slice.call(arguments, 1);
    } else if(arg1 && (arg1.type in listeners)) {
        stack = listeners[arg1.type];
        args = arguments;
    } else {
        return Promise.resolve(false);
    }

    if(!stack || !stack.length) {
        return Promise.resolve(true);
    }

    // Copy the listeners
    stack = stack.slice();

    return asyncExec(stack, this, args);
}

export function syncDispatchEvent(arg1) {
    let stack = [];
    let args = [];
    const listeners = this._listeners;

    if(typeof arg1 === 'string') {
        stack = listeners[arg1];
        args = Array.prototype.slice.call(arguments, 1);
    } else if(arg1 && (arg1.type in listeners)) {
        stack = listeners[arg1.type];
        args = arguments;
    } else {
        return false;
    }

    if(!stack || !stack.length) {
        return true;
    }

    // Copy the listeners
    stack = stack.slice();

    for(var i = 0, l = stack.length; i < l; i++) {
        const { listener } = stack[i];

        if(Reflect.apply(listener, this, args) === true) {
            return false;
        }
    }

    return true;
}

export function dispatchEvent(arg1) {
    let stack = [];
    let args = [];
    const listeners = this._listeners;

    if(typeof arg1 === 'string') {
        stack = listeners[arg1];
        args = Array.prototype.slice.call(arguments, 1);
    } else if(arg1 && (arg1.type in listeners)) {
        stack = listeners[arg1.type];
        args = arguments;
    } else {
        return Promise.resolve(false);
    }

    if(!stack || !stack.length) {
        return Promise.resolve(true);
    }

    // Copy the listeners
    stack = stack.slice();

    return exec(stack, this, args);
}