Function filenameDiff

src/render-utils.ts:145–205

(file: DiffFileName)

 *        returns "my/path/{to → for}/file.js"
 */
export function filenameDiff(file: DiffFileName): string {
  // TODO: Move unify path to parsing
  const oldFilename = unifyPath(file.oldName);
  const newFilename = unifyPath(file.newName);

  if (oldFilename !== newFilename && !isDevNullName(oldFilename) && !isDevNullName(newFilename)) {
    const prefixPaths = [];
    const suffixPaths = [];

    const oldFilenameParts = oldFilename.split(separator);
    const newFilenameParts = newFilename.split(separator);

    const oldFilenamePartsSize = oldFilenameParts.length;
    const newFilenamePartsSize = newFilenameParts.length;

    let i = 0;
    let j = oldFilenamePartsSize - 1;
    let k = newFilenamePartsSize - 1;

    while (i < j && i < k) {
      if (oldFilenameParts[i] === newFilenameParts[i]) {
        prefixPaths.push(newFilenameParts[i]);
        i += 1;
      } else {
        break;
      }
    }

    while (j > i && k > i) {
      if (oldFilenameParts[j] === newFilenameParts[k]) {
        suffixPaths.unshift(newFilenameParts[k]);
        j -= 1;
        k -= 1;
      } else {
        break;
      }
    }

    const finalPrefix = prefixPaths.join(separator);
    const finalSuffix = suffixPaths.join(separator);

    const oldRemainingPath = oldFilenameParts.slice(i, j + 1).join(separator);
    const newRemainingPath = newFilenameParts.slice(i, k + 1).join(separator);

    if (finalPrefix.length && finalSuffix.length) {
      return (
        finalPrefix + separator + '{' + oldRemainingPath + ' → ' + newRemainingPath + '}' + separator + finalSuffix
      );
    } else if (finalPrefix.length) {
      return finalPrefix + separator + '{' + oldRemainingPath + ' → ' + newRemainingPath + '}';
    } else if (finalSuffix.length) {
      return '{' + oldRemainingPath + ' → ' + newRemainingPath + '}' + separator + finalSuffix;
    }

    return oldFilename + ' → ' + newFilename;
  } else if (!isDevNullName(newFilename)) {
    return newFilename;
  } else {