diff --git a/test/vx/type_test.exs b/test/vx/type_test.exs
index fd558d1..f12f2c5 100644
--- a/test/vx/type_test.exs
+++ b/test/vx/type_test.exs
@@ -77,4 +77,19 @@ defmodule Vx.TypeTest do
       assert Vx.Type.constraints(schema) == Enum.reverse(constraints)
     end
   end
+
+  describe "of/1" do
+    test "plain type" do
+      of = [Vx.String.t, Vx.Integer.t]
+      type = %{Vx.Type.new(:foo, fn _ -> :ok end) | of: of}
+
+      assert Vx.Type.of(type) == of
+    end
+
+    test "wrapped type" do
+      type = Vx.List.t(Vx.String.t)
+
+      assert Vx.Type.of(type) == [Vx.String.t]
+    end
+  end
 end