export function areAllDiffFilesCollapsed(
  fileKeys: ReadonlyArray<string>,
  collapsedFileKeys: ReadonlySet<string>,
): boolean {
  return fileKeys.length > 0 && fileKeys.every((fileKey) => collapsedFileKeys.has(fileKey));
}

export function toggleAllDiffFiles(
  fileKeys: ReadonlyArray<string>,
  collapsedFileKeys: ReadonlySet<string>,
): ReadonlySet<string> {
  return areAllDiffFilesCollapsed(fileKeys, collapsedFileKeys) ? new Set() : new Set(fileKeys);
}