public void TEST_GetConcreteTypeName_GIVEN_UnsupportedShape_THEN_ItReturnsUnknownShape() { // Arrange var unSupportedShapeName = "Unsupported"; var unknownshpae = new UnknownShape(ErrorConst.UNKNOWN_SHAPE); mockUnknownShapeFactory.Setup(f => f.CreateShapeConcreteType(lengths)).Returns(unknownshpae); var target = new ShapeService(mockShapeFactory.Object, mockUnknownShapeFactory.Object, mockShapeValidator.Object); // Act var testResult = target.GetShapeConcreteTypeName(unSupportedShapeName, lengths); // Assert mockUnknownShapeFactory.Verify(factory => factory.CreateShapeConcreteType(lengths)); Assert.AreEqual(ErrorConst.UNKNOWN_SHAPE, testResult); }