message: fix arrayShuffle on empty input
diff: @@ -79,6 +79,10 @@ export function arrayChunk<T>(arr: T[], size: number): T[][] {
  // Based off of https://en.wikipedia.org/wiki/Fisher%E2%80%93Yates_shuffle#The_modern_algorithm
  export function arrayShuffle<T>(arr: T[]): T[] {
  + if (!arr.length) {
  + return arr;
  + }
  +
  let j, tmp;
  for (let i = arr.length - 1; i !== 0; i--) {
  