test: add test to produce error that bypasses repository interface

1 files changed, 23 insertions, 3 deletions

diff --git a/app/db/in_memory_repository_test.go b/app/db/in_memory_repository_test.go
index 37fcbe0..9c44fa7 100644
--- a/app/db/in_memory_repository_test.go
+++ b/app/db/in_memory_repository_test.go
@@ -15,9 +15,7 @@ func TestInMemoryRepository(t *testing.T) {
 
 	t.Run("Save", func(t *testing.T) {
 		t.Run("an invalid Sparkle", func(t *testing.T) {
-			err := storage.Save(t.Context(), &domain.Sparkle{Reason: "because"})
-
-			assert.Error(t, err)
+			assert.Error(t, storage.Save(t.Context(), &domain.Sparkle{Reason: "because"}))
 			assert.Equal(t, 0, len(storage.All(t.Context())))
 		})
 
@@ -93,6 +91,28 @@ func TestInMemoryRepository(t *testing.T) {
 		})
 	})
 
+	t.Run("All", func(t *testing.T) {
+		repository := NewRepository[*domain.Sparkle]()
+		require.NoError(t, repository.Save(t.Context(), &domain.Sparkle{
+			Sparklee: "@tanuki",
+			Reason:   "because",
+		}))
+
+		t.Run("prevents unintended modifications", func(t *testing.T) {
+			items := repository.All(t.Context())
+			require.Equal(t, 1, len(items))
+
+			sparkle := items[0]
+			sparkle.Reason = "haha"
+
+			assert.Equal(t, "because", repository.All(t.Context())[0].Reason)
+		})
+
+		t.Run("prevents race conditions", func(t *testing.T) {
+			t.Skip()
+		})
+	})
+
 	t.Run("Find", func(t *testing.T) {
 		t.Run("when the entity exists", func(t *testing.T) {
 			sparkle, err := domain.NewSparkle("@tanuki for testing this func")