StreamTest.user.js

// ==UserScript==
// @name Stream Test
// @namespace http://imspace.cn/gms
// @match *://*/*
// @grant GM_xmlhttpRequest
// ==/UserScript==

function getBodyChecker () {
    let c = 0;
    let ret = function (buffer) {
        const u8 = new Uint8Array(buffer)
        for (let i of u8) {
            const e = c & 0xFF
            if (i !== e) {
                throw new Error(`Wrong, expecting ${e}, but got ${i}`)
            }
            c++
        }
        ret.count = c
    }
    ret.count = 0
    return ret
}
function initUI () {
    let start = false
    const div = document.createElement('div')
    const btn = document.createElement('button')
    const progress = document.createElement('progress')
    btn.addEventListener('click', () => {
        if (start) return
        startTest((p) => progress.value = p)
        start = true
    })
    btn.innerText = 'Start Test'
    progress.value = 0
    progress.max = 100
    div.appendChild(btn)
    div.appendChild(progress)
    div.style.position = 'fixed'
    div.style.top = '0'
    div.style.left = '0'

    document.body.appendChild(div)
}
function startTest (cb) {
    const checker = getBodyChecker()
    const stop = 1024 * 1024
    let alerted = false
    let conf = {}
    let xhr
    conf.method = 'GET'
    conf.url = 'https://github.com/spacemeowx2/100mb/raw/master/100mb.bin'
    conf.responseType = 'moz-chunked-arraybuffer'
    conf.onprogress = ({response}) => {
        try {
            checker(response)
        } catch (e) {
            xhr.abort()
            if (!alerted) {
                alert('Wrong data')
                alerted = true
            }
        }
        cb(checker.count / stop * 100)
        if (checker.count > stop) {
            xhr.abort()
            if (!alerted) {
                alert('Support!')
                alerted = true
            }
        }
    }
    xhr = GM_xmlhttpRequest(conf)
}
initUI()