       }} = Showtime.lookup_performance(edit_code)
     end
 
-    test "lookup_performance/1 returns an error for an unknown edit code" do
+    test "returns an error for an unknown edit code" do
       assert {:error, :not_found} = Showtime.lookup_performance("unknown")
     end
-
-    test "lookup_performance!/2 gets a performance from the given contest by edit code" do
+  end
+
+  describe "lookup_performance!/2" do
+    test "gets a performance from the given contest by edit code" do
       %{
         id: id,
         edit_code: edit_code,

      assert_ids_match_unordered Showtime.list_performances(contest), [p1, p2, p3]
    end

    test "list_performances/1 preloads the performances' contest categories + categories" do
      %{contest_category: %{contest: c}} = insert(:performance)

      assert [%Performance{
        contest_category: %ContestCategory{category: %Category{}}
      }] = Showtime.list_performances(c)
    end

    test "get_performance!/2 gets a performance from the given contest by id" do
      %{id: id, contest_category: %{contest: c}} = insert(:performance)

      result = Showtime.get_performance!(c, id)
      assert result.id == id
    end

    test "get_performance!/2 raises an error if the performance isn't found in the given contest" do
      c = insert(:contest)
      %{id: id} = insert(:performance)

      assert_raise Ecto.NoResultsError, fn -> Showtime.get_performance!(c, id) end
    end

    test "get_performance!/2 preloads all associated data of the performance" do
      %{
        id: id,
        contest_category: %{contest: c}

        pieces: [%Piece{}]
      } = Showtime.get_performance!(c, id, edit_code)
    end
  end

  describe "lookup_performance/1" do
    test "gets a performance by its edit code" do
      %{id: id, edit_code: edit_code} = insert(:performance)

      assert {:ok, result} = Showtime.lookup_performance(edit_code)
      assert result.id == id
    end

    test "preloads the performance's contest category and contest" do
      %{edit_code: edit_code} = insert(:performance)

      assert {:ok, %Performance{
