     assert String.split("x-x-", "-", parts: 3, trim: true) == ["x", "x"]
   end
 
-  test "split with regex" do
+  test "split/2,3 with regex" do
     assert String.split("", ~r{,}) == [""]
     assert String.split("", ~r{,}, trim: true) == []
     assert String.split("a,b", ~r{,}) == ["a", "b"]

    assert String.capitalize("ﬁn") == "Fin"
  end

  test "replace_leading" do
    assert String.replace_leading("aa abc   ", "a", "b") == "bb abc   "
    assert String.replace_leading("__ abc   ", "_", "b") == "bb abc   "
    assert String.replace_leading("aaaaaaaa ", "a", "b") == "bbbbbbbb "

           == [<<6>>, "ab", <<5>>, "cdef", <<3, 0>>]
  end

  test "starts_with?/2" do
    assert String.starts_with? "hello", "he"
    assert String.starts_with? "hello", "hello"
    refute String.starts_with? "hello", []
