Add the testing gubbins

internal/repository/notestore.go

@@ -8,4 +8,5 @@ type NoteStore interface {
 	SaveNote(models.Note) (models.Note, error)
 	GetNoteByID(int) (models.Note, error)
 	GetAllNotes() ([]models.Note, error)
+	DeleteNoteByID(int) error
 }

internal/repository/notestore_test.go

@@ -46,3 +46,12 @@ func (m *mockNoteStore) getNoteAndIndexByID(id int) (models.Note, int, error) {
 func (m *mockNoteStore) GetAllNotes() ([]models.Note, error) {
 	return m.Notes, nil
 }
+
+func (m *mockNoteStore) DeleteNoteByID(id int) error {
+	_, index, err := m.getNoteAndIndexByID(id)
+	if err != nil {
+		return err
+	}
+	m.Notes = append(m.Notes[:index], m.Notes[index+1:]...)
+	return nil
+}