dedent.js

// Source code from https://github.com/MartinKolarik/dedent-js

module.exports = function dedent(templateStrings, ...values) {
  let matches = [];
  let strings =
    typeof templateStrings === "string"
      ? [templateStrings]
      : templateStrings.slice();

  // 1. Remove trailing whitespace.
  strings[strings.length - 1] = strings[strings.length - 1].replace(
    /\r?\n([\t ]*)$/,
    ""
  );

  // 2. Find all line breaks to determine the highest common indentation level.
  for (let i = 0; i < strings.length; i++) {
    let match;

    if ((match = strings[i].match(/\n[\t ]+/g))) {
      matches.push(...match);
    }
  }

  // 3. Remove the common indentation from all strings.
  if (matches.length) {
    let size = Math.min(...matches.map((value) => value.length - 1));
    let pattern = new RegExp(`\n[\t ]{${size}}`, "g");

    for (let i = 0; i < strings.length; i++) {
      strings[i] = strings[i].replace(pattern, "\n");
    }
  }

  // 4. Remove leading whitespace.
  strings[0] = strings[0].replace(/^\r?\n/, "");

  // 5. Perform interpolation.
  let string = strings[0];

  for (let i = 0; i < values.length; i++) {
    string += values[i] + strings[i + 1];
  }

  return string;
};