nelsonfncosta

const loadImage = src =>
  new Promise((resolve, reject) => {
    const img = new Image();
    img.onload = () => resolve(img);
    img.onerror = reject;
    img.src = src;
  });

nelsonfncosta

import React from 'react'
import Dropzone from 'react-dropzone'
import { act, fireEvent, render, waitFor } from '@testing-library/react'

test('invoke onDragEnter when dragenter event occurs', async () => {
  const file = new File([
    JSON.stringify({ping: true})
  ], 'ping.json', { type: 'application/json' })
  const data = mockData([file])
  const onDragEnter = jest.fn()

nelsonfncosta

let size = prompt("size?");
for(let i=1; i<=size; i++) console.log("#".repeat(i));

let size = prompt("size?")
for(let i=1; i<= size; i++){ 
    let buffer = ' '.repeat(size-i)
    let side = '#'.repeat(i-1)
    console.log(`${buffer}${side} ${side}${buffer}`); 
  } 

nelsonfncosta

nelsonfncosta

export function dragElement(elmnt, dragElement = elmnt) {
  let pos1 = 0;
  let pos2 = 0;
  let pos3 = 0;
  let pos4 = 0;

  dragElement.onmousedown = dragMouseDown;

  function dragMouseDown(e) {
    e = e || window.event;

nelsonfncosta

function arrayBufferToString (buffer, encoding = 'UTF-8', callback = console.log) {
  const blob = new Blob([buffer], { type: 'text/plain' })
  const reader = new FileReader()
  reader.onload = evt => callback(evt.target.result)
  reader.readAsText(blob, encoding)
}

nelsonfncosta

function streamToString (stream) {
  const chunks = []
  return new Promise((resolve, reject) => {
    stream.on('data', (chunk) => chunks.push(Buffer.from(chunk)))
    stream.on('error', (err) => reject(err))
    stream.on('end', () => resolve(Buffer.concat(chunks).toString('utf8')))
  })
}

nelsonfncosta

// Longhand
switch (data) {
  case 'a':
    test1();
  break;

  case 'b':
    test2();
  break;

nelsonfncosta

function findCustomerCity(name) {
  const texasCustomers = ['John', 'Ludwig', 'Kate']; 
  const californiaCustomers = ['Wade', 'Lucie','Kylie'];
  
  return texasCustomers.includes(name) ? 'Texas' : 
    californiaCustomers.includes(name) ? 'California' : 'Unknown';
};

// For every call, memory is unnecessarily re-allocated to the variables texasCustometrs and californiaCustomers .

nelsonfncosta

function readFile(file: File | null) {
  const reader = new FileReader();

  reader.addEventListener("load", (event) => {
    const result = event.target.result;

    console.log(result);
  });

  reader.addEventListener("progress", (event) => {