Topic: TDD for Bricscad examples

[MickD]

Hi Kerry,
the problem isn't really with Gallio, it's with the Gallio extension for testing AutoCAD. It is written only for AutoCAD and thus doesn't work with Bricscad as the AutoCAD lib's are tied to the build.
Getting it running is easy on AutoCAD once the bat file is set up.

I have a few more things to try with the Bricscad extension before I give up altogether.

[CADbloke]

Just a thought and not necessarily an good one ... is running tests inside AutoCAD / Bricscad is more like integration testing than unit testing? Perhaps is is more like behavio(u)ral testing too? ie. Do you want to test the result of the operation rather than the units of the operation? This is still testing and therefore valid but what I am trying to say (badly) is that the approach should be driven by what you are actually testing so there is probably a need for different types of tests for the same code.

Related to this - has anyone tried a Coded UI test in AutoCAD / Bricscad?

Hey, it's 8am and I've only just finished my first coffee. 

[MickD]

Just a thought and not necessarily an good one ... is running tests inside AutoCAD / Bricscad is more like integration testing than unit testing? ....

Yes, you are right there and that was the reason for using the mocks to isolate the actual implementation code. We should be able to write the implementation for out tests and mock them out as needed to make the tests pass and confirm our design/behaviour.

I think TDD includes all types of testing and integration testing is just as important as unit testing, it's just another hurdle I want to hobble over before I get too far along the process and testing against the cad api is the hardest.

I've made a bit of progress though, I've actually embedded the tests in the class library (these could be loaded separately of course) and it works fine, I just need to re-route the test output to a file or the command line somehow.

This code works fine and wouldn't be hard to automate the calls to each test from one command. You can see I'm not using mocks and it places the circle and then no circle but I have no feedback to whether it is a pass or fail.

Code - C#: [Select]

1. namespace CadEngine
2. {
3.     [TestFixture]
4.    
5.     class CadEngineDrawingTests
6.     {
7.         [CommandMethod("Test1")]
8.         public void AddObject_ToDrawing_ReturnsNonEmptyString()
9.         {
10.             var drawingObject = new MyCircle(50);
11.  
12.             // create our Drawing object passing in the mock dependency:
13.             var cadEngine = new CadEngine();
14.             var drawing = new Drawing(cadEngine);
15.  
16.             string objectId = drawing.AddObject(drawingObject);
17.  
18.             Assert.AreNotEqual(String.Empty, objectId);
19.         }
20.  
21.  
22.         [Test]
23.         [CommandMethod("Test2")]
24.         public void AddObject_ToDrawing_ReturnsEmptyString()
25.         {
26.             // no need to implement the mock return as it shouldn't reach the call:
27.             var cadEngine = new CadEngine();
28.             var drawing = new Drawing(cadEngine);
29.  
30.             // just pass in a null object, no need to 'null' anything to get the same result:
31.             string objectId = drawing.AddObject(null);
32.  
33.             Assert.AreEqual(String.Empty, objectId);
34.         }
35.     }
36.  
37.     /****** Class implementations for testing *********/
38.     public class Drawing : IDrawing
39.     {
40.         private ICadEngine _cadEngine;
41.  
42.         public Drawing(ICadEngine cadEngine)
43.         {
44.             _cadEngine = cadEngine;
45.         }
46.  
47.         public string AddObject(IDrawingObject drawingObject)
48.         {
49.             if (drawingObject != null)
50.                 return _cadEngine.AddObjectToDB(drawingObject);
51.             else
52.                 return String.Empty;
53.         }
54.     }
55. }
56.  

<edit> I think I might just write my own assertions and be done with it, they aren't that complicated really and can be more finely tuned to the cad api</edit.

[MickD]

I've written a basic assert class as proof of concept, seems to work ok

Code - C#: [Select]

1.     public class Assert
2.     {
3.         private static string GetCaller()
4.         {
5.             // this stack trace may have performance penalties later, it's a hack for now:
6.             System.Diagnostics.StackTrace trace = new System.Diagnostics.StackTrace();
7.             int caller = 2;
8.             System.Diagnostics.StackFrame frame = trace.GetFrame(caller);
9.             return frame.GetMethod().Name;
10.         }
11.  
12.         public static void AreEqual(string testValue, string returnedValue)
13.         {
14.             // if string is empty, format it so we can see:
15.             if (testValue == String.Empty) testValue = "\"\"";
16.             if (returnedValue == String.Empty) returnedValue = "\"\"";
17.  
18.             if (testValue != returnedValue)
19.             {
20.                 _AcAp.Application.DocumentManager
21.                     .MdiActiveDocument
22.                     .Editor
23.                     .WriteMessage(GetCaller() + " passed");
24.             }
25.             else
26.             {
27.                 _AcAp.Application.DocumentManager
28.                     .MdiActiveDocument
29.                     .Editor
30.                     .WriteMessage(GetCaller() + " FAILED: Expected "
31.                     + testValue + " - actual result: " + returnedValue);
32.             }
33.         }
34.  
35.         public static void AreNotEqual(string testValue, string returnedValue)
36.         {
37.             // if string is empty, format it so we can see:
38.             if (testValue == String.Empty) testValue = "\"\"";
39.             if (returnedValue == String.Empty) returnedValue = "\"\"";
40.  
41.             if (testValue == returnedValue)
42.             {
43.                 _AcAp.Application.DocumentManager
44.                     .MdiActiveDocument
45.                     .Editor
46.                     .WriteMessage(GetCaller() + " passed");
47.             }
48.             else
49.             {
50.                 _AcAp.Application.DocumentManager
51.                     .MdiActiveDocument
52.                     .Editor
53.                     .WriteMessage(GetCaller() + " FAILED: Expected "
54.                     + testValue + " - actual result: " + returnedValue);
55.             }
56.         }
57.     }
58.  

I added a 3rd test to fail on purpose that expected an empty string to see the output was correct.

[JohnK]

Just stopping in to say that this subject has lead me down a rabbit hole. I need to get back to my reading so I can write up some of my ideas. …great thread Mick.

[Kerry]

Just stopping in to say that this subject has lead me down a rabbit hole. I need to get back to my reading so I can write up some of my ideas. …great thread Mick.

Yes John, I've had to stop reading the thread (other than casual perusal) .. I was getting sucked in too.

This IS a great thread Mick !  ... I hope to catch up with it after I've slain a few dragons.

[MickD]

Glad you like it, just hope it's helping and not confusing the issue too much

I am tidying up the whole working solution and will put it on github later today/tonight, got a bit of real work to do this afternoon.

[Kerry]

Just for interest,
Have you tried UnitTests in Resharper inside Visual Studio Mick ?

[MickD]

Just for interest,
Have you tried UnitTests in Resharper inside Visual Studio Mick ?

I have but I'm not going to fork out 150 clams for it, it is great for refactoring but I also found it annoying (worse than VS) with the contextual help popups etc when you don't really want them.
Running the NUnit gui is easy and I just have it to the side of VS in the other window.
If you need any help setting it up I'll post up a quick tut but you basically just 'Open Project' from the NUnit gui menu and load the test assembly and hit run, of course this doesn't work within the cad system hence the above posts.

[Keith Brown]

As someone who is very new to Unit Testing (i.e. I had to read up on it to know what it means) I wonder if someone could post a very simple VS solution that has a small AutoCAD project and a unit testing project as an example?  I read the code excerpts in this thread and now I feel as if my IQ has dropped about 20 pts because I am completely lost.  Thanks in advance.

[MickD]

No prob's Keith, I'll clean this one up and post it a bit later.

Here's a link to Roy Osherove's vid's, the first one's a bit slow getting going but all are well worth the watch. Try to do some coding and then watch again

http://artofunittesting.com/

"Understanding Test Driven Development" is the first one to watch and a few others from that talk are also on that page, should be enough to get started with. As mentioned before, anything from 'Uncle Bob' on SOLID development will help as well when it comes to design problems.

[MickD]

Here's a VS2010 solution as it stands today, it is using Bricscad v14 lib's but you should be able to switch them out for AutoCAD with little work.

Tools required:
NuGet package manager should be installed in VS to manage the Nunit and Moq packages, this is a lot easier than loading all the requirements manually.
NUnit - download and install, I run it in the 'mini' setup which hides the output progress and messages, you can find the output by right clicking on the test to see any errors etc.

To run the tests in NUnit, start NUnit and go 'Open Project' and browse to the bin folder and select the dll with <ProjectName>.Tests.dll and you should be able to see and run the tests.
Repeat for the other test project/s.

<edit> Another confusing aspect of testing is 'how do you debug?', it can be done but really, the process of testing and running tests takes you straight to the problem if it fails anyway, you shouldn't need to debug at all, if you do your tests (or implementation code) have too much logic, another "code smell" if you like</edit>

[Keith Brown]

MickD,


Thank you very much for the links and the test project.  I will have some time in the next few weeks to consume this information and hopefully will have a much better understanding of how it all works.  My end goal is of course being able to write good tests but also better understand the process of separating the business layer from the data layer of the software.  And in the long run be able to write more reusable code.  It seems i am constantly coding the same things over and over again with new bugs every time i code it.

[MickD]

No problems Keith, it's not easy (else everyone would be doing it  ) but well worth the effort. I was a doubter until I kept seeing it pop up and read/watched a few talks for it to sink in, actually doing some coding really helps it hit home.

Just by writing the test first forces you to design and code better as a happy side effect and Interfaces (IoC) are the key. Even if you only watch/read one good talk on SOLID code and it's a bit daunting, start writing tests then the SOLID principles start to make sense as well.

[Jeff H]

Hey Mick,

Did you ever have moment where you were thinking TDD seems like it is not useful then you looked at project and realized Holy Sh*t I have almost a complete working code base for project and I did not spend hours(while driving, at night, etc..) thinking about what classes to create, abstractions, how each object will talk with one another, etc..... it just happened?