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Eirik L. Vullum eiriklv

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@joshdover
joshdover / README.md
Last active Oct 13, 2021
Idiomatic React Testing Patterns
View README.md

Idiomatic React Testing Patterns

Testing React components seems simple at first. Then you need to test something that isn't a pure interaction and things seem to break down. These 4 patterns should help you write readable, flexible tests for the type of component you are testing.

Setup

I recommend doing all setup in the most functional way possible. If you can avoid it, don't set variables in a beforeEach. This will help ensure tests are isolated and make things a bit easier to reason about. I use a pattern that gives great defaults for each test example but allows every example to override props when needed:

View module.md

Creating a redis Module in 15 lines of code!

A quick guide to write a very very simple "ECHO" style module to redis and load it. It's not really useful of course, but the idea is to illustrate how little boilerplate it takes.

Step 1: open your favorite editor and write/paste the following code in a file called module.c

#include "redismodule.h"
/* ECHO <string> - Echo back a string sent from the client */
int EchoCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
@spaze
spaze / opera-vpn.md
Last active Aug 23, 2021
Opera VPN behind the curtains is just a proxy, here's how it works
View opera-vpn.md

When setting up (that's immediately when user enables it in settings) Opera VPN sends few API requests to https://api.surfeasy.com to obtain credentials and proxy IPs, see below, also see The Oprah Proxy.

The browser then talks to a proxy de0.opera-proxy.net (when VPN location is set to Germany), it's IP address can only be resolved from within Opera when VPN is on, it's 185.108.219.42 (or similar, see below). It's an HTTP/S proxy which requires auth.

When loading a page with Opera VPN enabled, the browser sends a lot of requests to de0.opera-proxy.net with Proxy-Authorization request header.

The Proxy-Authorization header decoded: CC68FE24C34B5B2414FB1DC116342EADA7D5C46B:9B9BE3FAE674A33D1820315F4CC94372926C8210B6AEC0B662EC7CAD611D86A3 (that's sha1(device_id):device_password, where device_id and device_password come from the POST /v2/register_device API call, please note that this decoded header is from another Opera installation and thus contains

@rauchg
rauchg / README.md
Last active Feb 19, 2021
require-from-twitter
View README.md
@dmvaldman
dmvaldman / promisesEM.md
Last active Aug 23, 2021
Promises as EventEmitters
View promisesEM.md

Promises as EventEmitters

I was trying to understand JavaScript Promises by using various libraries (bluebird, when, Q) and other async approaches.

I read the spec, some blog posts, and looked through some code. I learned how to

View README.md

The issue:

..mobile browsers will wait approximately 300ms from the time that you tap the button to fire the click event. The reason for this is that the browser is waiting to see if you are actually performing a double tap.

(from a new defunct https://developers.google.com/mobile/articles/fast_buttons article)

touch-action CSS property can be used to disable this behaviour.

touch-action: manipulation The user agent may consider touches that begin on the element only for the purposes of scrolling and continuous zooming. Any additional behaviors supported by auto are out of scope for this specification.

View usable-promises.js
// from the brilliant mind of sb
var _catch = Promise.prototype.catch;
Promise.prototype.catch = function () {
return _catch.call(this, function (err) { setTimeout(function () { throw(err); }, 0); });
}
@Avaq
Avaq / combinators.js
Last active Oct 20, 2021
Common combinators in JavaScript
View combinators.js
const I = x => x
const K = x => y => x
const A = f => x => f (x)
const T = x => f => f (x)
const W = f => x => f (x) (x)
const C = f => y => x => f (x) (y)
const B = f => g => x => f (g (x))
const S = f => g => x => f (x) (g (x))
const S_ = f => g => x => f (g (x)) (x)
const S2 = f => g => h => x => f (g (x)) (h (x))
View runtimer.js
function* runTimer(getState) {
while(yield take('START')) {
while(true) {
const {stop, tick} = yield race({
stop : take('STOP'),
tick : call(wait, ONE_SECOND);
})
if ( !stop ) {
yield put(actions.tick());
View notes.js
// devDependencies in package.json:
"require-reload": "0.2.2",
"react-transform-hmr-no-accept": "1.0.1", // not published, get it here: https://github.com/brandonbloom/react-transform-hmr
// in babelrc:
"env": {
"development": {
"plugins": [