public async Task PostCreateMonsterAsync_ShouldCreateMonster_ThenReturnMonsterResponse() { const int groupId = 8; var createMonsterRequest = new CreateMonsterRequest(); var createdMonster = new Monster(); var monsterResponse = new MonsterResponse(); _monsterService.CreateMonsterAsync(_executionContext, groupId, createMonsterRequest) .Returns(createdMonster); _mapper.Map <MonsterResponse>(createdMonster) .Returns(monsterResponse); var result = await _controller.PostCreateMonsterAsync(_executionContext, groupId, createMonsterRequest); result.Value.Should().BeSameAs(monsterResponse); result.StatusCode.Should().Be(StatusCodes.Status201Created); }