michalkot

function weightedRandom(ar) {
	var ar = ar.sort(x => x.w);
	var sum = ar.reduce((p, c) => p + c.w, 0);
	// normalise
	var soFar = 0;
	ar.map(o => {
		o.w = o.w / sum;
		o.w += soFar;
		soFar += o.w;
	});

lightsofapollo

SlowDescribeReporter.prototype = {

    threshold: 400,

    reportRunnerStarting: function(runner){
        var i, len, suites = runner.suites_, self = this;
        this.topLevels = {};

        for(i = 0, len = suites.length; i < len; i++){
            (function(exec){

ChrisPenner

const all = (...preds) => (obj) => preds.map(f => f(obj)).reduce((a, b) => a && b, true)
const any = (...preds) => (obj) => preds.map(f => f(obj)).reduce((a, b) => a || b, false)
const oneOf = (...preds) => (obj) => preds.map(f => f(obj)).reduce((a, b) => a ? !b : b, false)
const has = (prop) => (obj) => obj[prop] !== undefined
const not = (pred) => (obj) => !pred(obj)
const equals = (prop, val) => (obj) => obj[prop] === val
const implies = (f, g) => (obj) => !f(obj) || g(obj);

const validate = all(implies(has('selectedIndex'), equals('isOpen', true)))

jondlm

React introduced shallow rendering in 0.13. This is an excellent feature that I wish was included earlier in React. It aims to solve the problem of unit testing components without going through a real, or jsdom mocked, DOM. I couldn't find any info online about what lifecycle events it actually fires. So I did some testing of my own. To reproduce, put component.js and test.js into a folder and run node test.js.

TLDR; shallow rendering only invokes the following lifecycle hooks (in order):

1. getDefaultProps
2. getInitialState
3. componentWillMount stops here until re-render
4. componentWillReceiveProps
5. shouldComponentUpdate
6. componentWillUpdate

ryanspradlin

type BatchLoadFn<K, V> = (keys: Array<K>) => Promise<Array<V | Error>>;

type LoadAllFn<K, V> = () => Promise<Array<[K, V]>>;

type Options<K, V> = {
  batch?: boolean,
  cache?: boolean,
  cacheMap?: CacheMap<K, Promise<V>>,
  cacheKeyFn?: (key: any) => any
};

etagwerker

#!/usr/bin/env python3
import sys
import os


def curl_to_ab(curl_cmd: list, num: int=200, cur: int=4) -> str:
    """
    Translate a cURL command created by Chrome's developer tools into a
    command for ``ab``, the ApacheBench HTTP benchmarking tool.

xialvjun

// https://github.com/lodash/lodash/issues/1696
import {clone, setWith, curry} from 'lodash/fp';

// export const setIn = curry((path, value, obj) =>
//   setWith(clone, path, value, clone(obj)),
// );
export const setIn = curry((obj, path, value) =>
  setWith(clone, path, value, clone(obj)),
);

acdlite

Demo: Coordinating async React with non-React views

tl;dr I built a demo illustrating what it might look like to add async rendering to Facebook's commenting interface, while ensuring it appears on the screen simultaneous to the server-rendered story.

A key benefit of async rendering is that large updates don't block the main thread; instead, the work is spread out and performed during idle periods using cooperative scheduling.

But once you make something async, you introduce the possibility that things may appear on the screen at separate times. Especially when you're dealing with multiple UI frameworks, as is often the case at Facebook.

How do we solve this with React?

ctolsen

#!/usr/bin/env python3
import sys
import os


def curl_to_ab(curl_cmd: list, num: int=200, cur: int=4) -> str:
    """
    Translate a cURL command created by Chrome's developer tools into a
    command for ``ab``, the ApacheBench HTTP benchmarking tool.

koba04

https://webkit.org/blog/10218/full-third-party-cookie-blocking-and-more/

1. Does Safari block 3rd party cookies with SameSite=None?

I've created to test it, but I'm confused by the result. https://animated-caribou.glitch.me/

The result

• Chrome: only display the cookie value with SameSite=None in iframe.