fix (graphql): handle unbound range

test/wabanex_web/schema/types/custom/date_range_test.exs

@@ -28,6 +28,7 @@ defmodule WabanexWeb.Schema.Types.Custom.DateRangeTest do
     test "serialize a list of dates as a list of ISO8601 date strings" do
       assert "1978-12-15,1980-02-13" == serialize(:date_range, [~D[1978-12-15], ~D[1980-02-13]])
       assert "1978-12-15," == serialize(:date_range, [~D[1978-12-15], nil])
+      assert "1978-12-15," == serialize(:date_range, [~D[1978-12-15], :unbound])
     end
 
     test "serialize a postgres range as a list of ISO8601 date strings" do
@@ -35,6 +36,7 @@ defmodule WabanexWeb.Schema.Types.Custom.DateRangeTest do
                serialize(:date_range, DateRange.new(~D[1978-12-15], ~D[1980-02-13]))
 
       assert "1978-12-15," == serialize(:date_range, DateRange.new(~D[1978-12-15], nil))
+      assert "1978-12-15," == serialize(:date_range, DateRange.new(~D[1978-12-15], :unbound))
     end
 
     test "can be parsed from a string of ISO8601" do
@@ -43,9 +45,6 @@ defmodule WabanexWeb.Schema.Types.Custom.DateRangeTest do
 
       assert {:ok, DateRange.new(~D[1978-12-15], nil)} ==
                parse(:date_range, %Input.String{value: "1978-12-15"})
-
-      assert {:ok, DateRange.new(~D[1978-12-15], :unbound)} ==
-               parse(:date_range, %Input.String{value: "1978-12-15"})
     end
   end
 end