code: function squashTokens (tokens) {
      var squashedTokens = [];
  
      var token, lastToken;
      for (var i = 0, numTokens = tokens.length; i < numTokens; ++i) {
        token = tokens[i];
  
        if (token) {
          if (token[0] === 'text' && lastToken && lastToken[0] === 'text') {
            lastToken[1] += token[1];
            lastToken[3] = token[3];
          } else {
            squashedTokens.push(token);
            lastToken = token;
          }
        }
      }
  
      return squashedTokens;
    }
docs: Combines the values of consecutive text tokens in the given `tokens` array
  to a single token.