Allow integer time units for DateTime.from_unix!/2 (#8801)

2 files changed, 19 insertions, 1 deletions

diff --git a/lib/elixir/lib/calendar/datetime.ex b/lib/elixir/lib/calendar/datetime.ex
index 1744fd11f..34a5b7a08 100644
--- a/lib/elixir/lib/calendar/datetime.ex
+++ b/lib/elixir/lib/calendar/datetime.ex
@@ -160,9 +160,11 @@ defmodule DateTime do
       iex> DateTime.from_unix!(1_432_560_368_868_569, :microsecond)
       #DateTime<2015-05-25 13:26:08.868569Z>
 
+      iex> DateTime.from_unix!(143_256_036_886_856, 1024)
+      #DateTime<6403-03-17 07:05:22.320Z>
   """
   @spec from_unix!(integer, :native | System.time_unit(), Calendar.calendar()) :: t
-  def from_unix!(integer, unit \\ :second, calendar \\ Calendar.ISO) when is_atom(unit) do
+  def from_unix!(integer, unit \\ :second, calendar \\ Calendar.ISO) do
     case from_unix(integer, unit, calendar) do
       {:ok, datetime} ->
         datetime
diff --git a/lib/elixir/test/elixir/calendar/datetime_test.exs b/lib/elixir/test/elixir/calendar/datetime_test.exs
index e023f4bf5..4c0d0e411 100644
--- a/lib/elixir/test/elixir/calendar/datetime_test.exs
+++ b/lib/elixir/test/elixir/calendar/datetime_test.exs
@@ -216,6 +216,14 @@ defmodule DateTimeTest do
     }
 
     assert DateTime.from_unix(-1, :microsecond) == {:ok, minus_datetime}
+
+    assert_raise ArgumentError, fn ->
+      DateTime.from_unix(0, :unknown_atom)
+    end
+
+    assert_raise ArgumentError, fn ->
+      DateTime.from_unix(0, "invalid type")
+    end
   end
 
   test "from_unix!/2" do
@@ -240,6 +248,14 @@ defmodule DateTimeTest do
     assert_raise ArgumentError, fn ->
       DateTime.from_unix!(-377_705_116_801)
     end
+
+    assert_raise ArgumentError, fn ->
+      DateTime.from_unix!(0, :unknown_atom)
+    end
+
+    assert_raise ArgumentError, fn ->
+      DateTime.from_unix!(0, "invalid type")
+    end
   end
 
   test "to_unix/2 works with Unix times back to 0 Gregorian seconds" do