Dedent code block

dedent.js

export function dedent(code) {
  let spacesToTrim;
  return code.split('\n').reduce((acc, line) => {
    if (line.trim().length) {
      if (spacesToTrim === undefined) {
        spacesToTrim = /^\s*/.exec(line)[0].length;
      }
      acc += line.substring(spacesToTrim) + '\n';
    } else acc += '\n';
    return acc;
  }, '');
}