public void Get_All_LibraryCards() { var mockSet = BuildMock(); var mockCtx = new Mock <LibraryDbContext>(); mockCtx.Setup(c => c.LibraryCards).Returns(mockSet.Object); var sut = new LibraryCardService(mockCtx.Object); var queryResult = sut.GetAll().ToList(); queryResult.Should().AllBeOfType(typeof(LibraryCard)); queryResult.Should().HaveCount(2); queryResult.Should().Contain(a => a.Id == 1); queryResult.Should().Contain(a => a.Id == 2); }