@Test
    public void create_ShouldThrowExc_When_BeerNameAlreadyExists() {
        // Arrange
        Beer mockBeer = createMockBeer();
        var mockUser = createMockUser();
        Mockito.when(mockRepository.getByName(mockBeer.getName())).thenReturn(mockBeer);

        // Act
        Beer result = service.getBeerById(1);

        // Assert
        Assertions.assertThrows(DuplicateEntityException.class, () -> service.create(mockBeer, mockUser));
    }