ilblog

Inspiration

• https://semisignal.com/tag/ffmpeg-js/
• https://github.com/antimatter15/whammy

ffmeg as worker can be found at https://github.com/Kagami/ffmpeg.js/

Final build can be obtained via wget https://unpkg.com/[email protected]/ffmpeg-worker-mp4.js

the0neWhoKnocks

Jest Testing Examples

• Common Use Cases
  • Testing a function was called with a specific Object property
  • Testing a function was called with a bound callback
  • Setting props on window.location
  • Working with History
  • Time travel
  • Testing exceptions
• Check if an Object contains multiple keys

bellbind

"use strict";

const fs = require("fs");
const names = process.argv.slice(2);
names.forEach(name => {
    const hash = require("crypto").createHash("sha256");
    const rs = fs.createReadStream(name);
    rs.on("readable", _ => {
        const buf = rs.read();
        if (buf) hash.update(buf);

robertknight

Istanbul Notes

These are some notes I made while reviewing hypothesis/client#156 to understand how Istanbul works

Istanbul instruments code in order to generate code coverage metrics for tests by adding code to record lines, statements etc. that are executed.

It adds a global __coverage__ variable to the generated code which is a map from file path to coverage information. The code for each module is then augmented with:

LeCoupa

#!/bin/bash
#####################################################
# Name: Bash CheatSheet for Mac OSX
# 
# A little overlook of the Bash basics
#
# Usage:
#
# Author: J. Le Coupanec
# Date: 2014/11/04

jboner

Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference                           0.5 ns
Branch mispredict                            5   ns
L2 cache reference                           7   ns                      14x L1 cache
Mutex lock/unlock                           25   ns
Main memory reference                      100   ns                      20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy             3,000   ns        3 us
Send 1K bytes over 1 Gbps network       10,000   ns       10 us
Read 4K randomly from SSD*             150,000   ns      150 us          ~1GB/sec SSD