hashTagGen.js

function generateHashtag (str) {
  // remove unnecessary spaces and make words capitalize
  function capitaLize(string) {
    if (string) {
      return string.replace(/^./, string[0].toUpperCase());
    }
  }
  // remove extra spaces from both sides of a string.
  const actualString = str.trim();
  if (actualString) {
    let arr = actualString.split(' ').map(word => capitaLize(word));
    const hashTag = "#"+arr.join('');
    // if the string length is till 140 chars long take it otherwise return false
    if (hashTag.length < 141) {
      return hashTag;
    }
    return false;
  }
  return false;
}