Adding some testing around updating notes

internal/repository/notes.go

@@ -20,7 +20,7 @@ func (r *NoteRepository) CreateNote(content string) (models.Note, error) {
 		return models.Note{}, fmt.Errorf("content cannot be empty")
 	}
 	note := models.Note{
-		Content: content,
+		Content:    content,
 		LastUpdate: time.Now(),
 	}
 	return r.store.SaveNote(note)
@@ -33,3 +33,7 @@ func (r *NoteRepository) GetNote(id int) (models.Note, error) {
 func (r *NoteRepository) ListNotes() ([]models.Note, error) {
 	return r.store.GetAllNotes()
 }
+
+func (r *NoteRepository) UpdateNote(id int, content string) (models.Note, error) {
+	return models.Note{}, fmt.Errorf("not implemented")
+}

internal/repository/notes_test.go

@@ -53,7 +53,7 @@ func TestCreateNote(t *testing.T) {
 				if tc.expectedError {
 					if err == nil {
 						t.Errorf("expected an error but got none")
-				}
+					}
 				} else {
 					if err != nil {
 						t.Errorf("unexpected error: %v", err)
@@ -197,3 +197,71 @@ func TestListNotes(t *testing.T) {
 		})
 	}
 }
+
+func TestUpdateNote(t *testing.T) {
+	notes := []models.Note{
+		{ID: 1, LastUpdate: time.Date(1984, 11, 20, 0, 0, 0, 0, time.UTC), Content: "First note"},
+		{ID: 2, LastUpdate: time.Date(2018, 6, 8, 0, 0, 0, 0, time.UTC), Content: "Second note"},
+	}
+	store := &mockNoteStore{Notes: notes}
+	repo := repository.NewNoteRepository(store)
+	testcases := []struct {
+		name          string
+		id            int
+		content       string
+		expectedNote  models.Note
+		expectedError bool
+	}{
+		{
+			name:    "Update existing note",
+			id:      1,
+			content: "Updated first note",
+			expectedNote: models.Note{
+				ID:         1,
+				LastUpdate: time.Date(2000, 1, 1, 0, 0, 0, 0, time.UTC),
+				Content:    "Updated first note",
+			},
+			expectedError: false,
+		},
+		{
+			name:          "Update non-existing note",
+			id:            999,
+			content:       "This note does not exist",
+			expectedNote:  models.Note{},
+			expectedError: true,
+		},
+		{
+			name:          "Update with empty content",
+			id:            2,
+			content:       "",
+			expectedNote:  models.Note{},
+			expectedError: true,
+		},
+	}
+	for _, tc := range testcases {
+		t.Run(tc.name, func(t *testing.T) {
+			synctest.Test(t, func(t *testing.T) {
+				note, err := repo.UpdateNote(tc.id, tc.content)
+				if tc.expectedError {
+					if err == nil {
+						t.Errorf("expected an error but got none")
+					}
+				} else {
+					if err != nil {
+						t.Errorf("unexpected error: %v", err)
+					}
+				}
+				if note.Content != tc.expectedNote.Content {
+					t.Errorf("expected content %q but got %q", tc.expectedNote.Content, note.Content)
+				}
+				if note.ID != tc.expectedNote.ID {
+					t.Errorf("expected ID %d but got %d", tc.expectedNote.ID, note.ID)
+				}
+				if !note.LastUpdate.Equal(tc.expectedNote.LastUpdate) {
+					t.Errorf("expected LastUpdate %v but got %v", tc.expectedNote.LastUpdate, note.LastUpdate)
+				}
+				fmt.Printf("Test case '%s' passed.\n", tc.name)
+			})
+		})
+	}
+}

internal/repository/notestore_test.go

@@ -11,18 +11,36 @@ type mockNoteStore struct {
 }
 
 func (m *mockNoteStore) SaveNote(note models.Note) (models.Note, error) {
-	note.ID = len(m.Notes) + 1
-	m.Notes = append(m.Notes, note)
+	// Save a note
+	if note.ID == 0 {
+		note.ID = len(m.Notes) + 1
+		m.Notes = append(m.Notes, note)
+		return note, nil
+	}
+	// Update a note
+	_, index, err := m.getNoteAndIndexByID(note.ID)
+	if err != nil {
+		return models.Note{}, err
+	}
+	m.Notes[index] = note
 	return note, nil
 }
 
 func (m *mockNoteStore) GetNoteByID(id int) (models.Note, error) {
-	for _, note := range m.Notes {
+	note, _, err := m.getNoteAndIndexByID(id)
+	if err != nil {
+		return models.Note{}, err
+	}
+	return note, nil
+}
+
+func (m *mockNoteStore) getNoteAndIndexByID(id int) (models.Note, int, error) {
+	for i, note := range m.Notes {
 		if note.ID == id {
-			return note, nil
+			return note, i, nil
 		}
 	}
-	return models.Note{}, fmt.Errorf("note with ID %d not found", id)
+	return models.Note{}, -1, fmt.Errorf("note with ID %d not found", id)
 }
 
 func (m *mockNoteStore) GetAllNotes() ([]models.Note, error) {