public async Task Get_Archetypes_WhenCalled_With_A_ArchetypeId_Should_Return_FileContentResult() { // Arrange const int archetypeId = 322; _mediator.Send(Arg.Any <IRequest <ArchetypeImageByIdQueryResult> >()).Returns(new ArchetypeImageByIdQueryResult { ContentType = "image/jpeg", Image = new byte[] { 1, 2, 3, 4, 5 } }); // Act var result = await _sut.Archetypes(archetypeId); // Assert result.Should().BeOfType <FileContentResult>(); }