Promise.all索引[副本]

这个 Promise.all

let promises = [Promise.resolve(true), 
                Promise.resolve(true), 
                Promise.resolve(false), 
                Promise.resolve(true)];

Promise.all(promises).then(result => {
    console.log(result);
    // [true, true, false, true]

    let failed = result.findIndex(r => !r);
    console.log(promises[failed]);

});

现在这是假设顺序始终保持不变,即结果数组始终与输入数组的顺序相同?