Based on the article http://blog.8thlight.com/uncle-bob/2012/04/20/Why-Is-Estimating-So-Hard.html we did this kata in the team

word-wrap-kata.js

// doing the above kata with the crewmeister team, yeah

const text = 'Four score and seven years ago our fathers brought forth upon this continent a new nation, conceived in liberty and dedicated to the proposition that all men are created equal';
const maxCharactersPerLine = 13;

const SEPARATOR = ' ';
const splitUpIntoWords = (s) => s.split(SEPARATOR);
const joining = (line) => line.join(SEPARATOR);

const textFormatter = () => {
  const parts = splitUpIntoWords(text);
  
  let index = 0;
  let formatted = [];
  while (index < parts.length) {
    let newLine = thePartsFrom(parts, index);
    formatted.push(newLine);
    index = index + newLine.length;
  }
  return formatted.map(joining);
}

const thePartsFrom = (parts, index) => {
  const firstWord = parts[index + 0];
  const secondWord = parts[index + 1];
  const thirdWord = parts[index + 2];
  
  if ([firstWord, secondWord, thirdWord].join(' ').length <= maxCharactersPerLine) {
    return [firstWord, secondWord, thirdWord];
  }                         
  if ([firstWord, secondWord].join(' ').length <= maxCharactersPerLine) {
    return [firstWord, secondWord];
  }                        
  return [firstWord];
}

describe('estimation kata', function() {
  
  it('split up the words', () => {
    const s = 'a b c';
    assert.deepEqual(['a', 'b', 'c'], splitUpIntoWords(s));
  });
  
  it('first line is "Four score"', () => {
    const [firstLine] = textFormatter(text);
    assert.equal("Four score", firstLine);
  });
  
  it('second line is "and seven"', () => {
    const [,secondLine] = textFormatter(text);
    assert.equal("and seven", secondLine);
  });
  
  it('third line is "years ago our"', () => {
    const [,,thirdLine] = textFormatter(text);
    assert.equal("years ago our", thirdLine);
  });
  
  it('fourth line is "fathers"', () => {
    const [,,,fourthLine] = textFormatter(text);
    assert.equal("fathers", fourthLine);
  });

});