apidoc-light/lib/core/utils/unindent.js

RESTful web API Documentation Generator

/**
 * Strips from each line any leading whitespace that is shared by all lines.
 *
 * @param str string
 * @returns string
 */
module.exports = function unindent (str) {
  const lines = str.split('\n');

  const xs = lines.filter(function (x) {
    return /\S/.test(x);
  }).sort();

  if (xs.length === 0) { return str; }

  const a = xs[0];
  const b = xs[xs.length - 1];

  const maxLength = Math.min(a.length, b.length);

  let i = 0;
  while (i < maxLength &&
           /\s/.test(a.charAt(i)) &&
           a.charAt(i) === b.charAt(i)) {
    i += 1;
  }

  if (i === 0) { return str; }

  return lines.map(function (line) {
    return line.substr(i);
  }).join('\n');
};