"Watin + Gallio + IE" performs badly? - watin

I am having around 300 Watin tests and I run them in IE using Gallio test runner. These tests take around three and half hours to run completely. I was wondering if everyone here sees the same kind of performance with Watin or I'm doing something terribly wrong. In this regard I would like to know if
You are using any specific browser/test runner that makes watin tests run fast
You are following any specific design pattern that enables running watin tests in parallel
You are following any design pattern that allows me to run multiple tests in the same browser instance so that I do not have to close and open the browser after every test

I don't know about running them in parallel, but you can certainly re-use the same browser instance, you just need a static reference to it. I'm using MSpec so the code is a bit different, but if you just have a static class containing the browser reference or similar, that should sort it.
The author also wrote a blog about it, but this method is much more complex than anything I've had to do:
http://watinandmore.blogspot.com/2009/03/reusing-ie-instance-in-vs-test.html
Another think to check is that you're not 'typing' text unless you need to. For example this:
browser.TextField(Find.ByName("q")).TypeText("WatiN");
Takes much longer than this:
browser.TextField(Find.ByName("q")).Value = "WatiN";
Because in the first line, it types each character individually. You may need to do this to check your JavaScript, but often you don't.

Related

While using test driven development, should i remove previous tests if I know they work

I am currently doing a project for college and it requires me to write a simple program with a few methods. Every time I create a new method I copy the previous test, and then add that method to the test. Currently I have 4 tests with all 4 methods being tested in the fourth. Should I remove the first and second test which only test the first method, and then the first and second method. Sorry if this is confusing. Thanks
That's not how test-driven development (TDD) is usually done. TDD usually serves two purposes:
By writing the test first, you get feedback on the usability of your API design. A unit test uses the API of the System Under Test (SUT), so if the test is difficult to write, the SUT is difficult to use.
The tests subsequently become artefacts that serve as regression tests.
Test code is also code, and comes with the same maintenance cost as regular code. It should be kept to the same standard as all other code, since you'll have to maintain it for the lifetime of the code base.
For that reason, rules about duplication, cohesion, coupling, etc. also apply for tests. In other words, don't copy and paste.
I've never heard about anyone following the process described in the OP.
Each test should test only one thing.

Unit Testing highly interdependent code

So I have some challenging code I would like to refactor. The challenge is that it depends on Database queries, EJB and Java serverFaces. Not simultaneously but close to it.
A good example would be a geocoder. Getting meaningful results depending on multiple queries to the DB depending on the data entered and stored. The code might also reference other helper classes and look them up via the JSF framework.
What are the best strategies for testing this sort of code? Should I try to separate out my code as much as possible? Should I use mocking instead? What has worked for other people?
Well, the short answer is "yes".
You're going to need, first of all, to factor the code sufficiently to construct unit tests at all. What you're describing is excessively complicated to apply the usual unit test methods, and what you would get in any case is more like a higher-level acceptance test.
Now, as far as that factoring goes, you have several possible approaches, and you will probably use them all.
Test the data base queries themselves, using an external script.
Construct an appropriate mock for the components directly accessing the DB, in order to see what happens against known results.
Build unit tests using a JUnit like framework for units of functionality.
Examine the state of the art to see if you can usefully test the output HTML against unit tests.

Test Driven Development - What exactly is the test?

I've been learning what TDD is, and one question that comes to mind is what exactly is the "test". For example, do you call the webservice and then build the code to make it work? or is it more unit testing oriented?
In general the test may be...
unit test which tests an individual subcomponent of your software without any external dependencies to other classes
integration test which are tests that test the connection between two separate systems, ie. their integration capability
acceptance test for validating the functionality of the system
...and some others I've most likely temporarily forgotten for now.
In TDD, however, you're mostly focusing on the unit tests when creating your software.
It's entirely Unit Test driven.
The basic idea is to write the unit tests first, and then do the absolute minimum amount of work necessary to pass the tests.
Then write more tests to cover more of the requirements, and implement a bit more to make it pass.
It's an iterative process, with cycles of test writing, and then code writing.
Here are a couple of good articles by Unclebob
Three rules of TDD
TDD with Acceptance and Unit tests
I suggest you not to emphasize on Test because TDD is actually is a software development methodology, not a testing methodology.
I would say it is about unit testing and code coverage. It is about shipping bugless code and being able to make changes easily in the future.
See Uncle Bob's words of wisdom.
How I use it, it's unit testing oriented. Suppose I want a method that square ints I write this method :
int square(int x) { return null; }
and then write some tests like :
[Test]
TestSquare()
{
Assert.AreEqual(square(0),0);
Assert.AreEqual(square(1),1);
Assert.AreEqual(square(10),100);
Assert.AreEqual(square(-1),1);
Assert.AreEqual(square(-10),100);
....
}
Ok, maybe square is a bad example :-)
In each case I test expected behaviour and all borderline vals like maxint and zero and null-value (remember you can test on errors too) and see to it the test fails (which isn't hard :-)) then I keep working on the function until it works.
So : first a unit test that fails an covers what you want it to cover, then the method.
Generally, unit tests in "TDD" shouldn't involve any IO at all.
In fact, you'll have a ton more effectiveness if you write objects that do not create side effects (I/O is almost always, if not always, a side effect!), and define your the behavior of your class either in terms of return values of methods, or calls made to interfaces that have been passed into the object.
I just want to give my view on the topic which may help to understand TDD a bit more in a different way.
TDD is a design method that relies in testing first. because you asked about how the test is, ill go like this:
If you want to build an application, you know the purpose of what you want to build and you know generally that when you are done, or along the way you need to test it e.g check the values of variables you create by code inspection, of quickly drop a button that you can click on and will execute a part of code and pop up a dialog to show the result of the operation etc.
on the other hand TDD changes your mindset and i'll point out one of such ways. commonly , you just rely on the development environment like visual studio to detect errors as you code and compile and somewhere in your head, you know the requirement and just coding and testing via button and pop ups or code inspection. I call this style SDDD (Syntax debugging driven development ).
but when you are doing TDD, is a "semantic debugging driven development " because you write down your thoughts/ goals of your application first by using tests (which and a more dynamic and repeatable version of a white board) which tests the logic (or "semantic") of your application and fails whenever you have a semantic error even if you application passes syntax error (upon compilation).
by the way even though i said "you know the purpose of what you want to build ..", in practice you may not know or have all the information required to build the application , since TDD kind of forces you to write tests first, you are compelled to ask more questions about the functioning of the application at a very early stage of development rather than building a lot only to find out that a lot of what you have written is not required (or at lets not at the moment). you can really avoid wasting your precious time with TDD (even though it may not feel like that initially)

How to test-drive software that uses external command-line tools

I'm trying to figure out how to test-drive software that launches external processes that take file paths as an input and write output after lengthy processing to stdout or some file? Is there some common patterns on writing tests in this kind of situations? It is hard to create fast executing tests that could verify correct usage of external tools without launching actual tools in tests and inspecting the results.
You could memoize (http://en.wikipedia.org/wiki/Memoization) the external processes. Write a wrapper in Ruby that computes the md5 sum of the input file and checks it against a database of known checksums. If it matches one, copy over the right output; otherwise, invoke the tool normally.
Test right up to your boundaries. In your case, the boundary is the command-line that you construct to invoke the external program (which you can capture by monkey patching). If you're gluing yourself in to that program's stdout (or processing its result by reading files) that's another boundary. The test is whether your program can process that "input".
The 90%-case answer would be to mock the external command-line tools and verify that the right input is being passed to them at the dividing interface between the two. This helps keep the test suite fast. Also you shouldn't have to bring in the command-line tools since they are not 'your code under test' - it brings in the possibility that the unit test could fail either due changes to your code or some change in behavior in the command line utility.
But it seems like you're having trouble defining the 'right input' - in which case using Optimizations like Memoization (as Dave suggests) might give you the best of both worlds.
Assuming the external programs are well-tested, you should just test that your program is passing the correct data to them.
I think you are getting into a common issue with unit testing, in that correctness is really determined by if the integration works, so how does the unit test help you?
The basic answer is that the unit test tests that the parameters you intend to pass to command line tool are in fact getting passed that way, and that the results you anticipate getting back are in fact processed the way you intend to process them.
Then there is a second level of tests, which may or may not be automated (preferably they are, but it does depend on if it is practical), which are at the functional level where the real utilities are called so that you can see that what you intend to pass and what you anticipate getting back match what actually happens.
There would also be nothing wrong with a set of tests which "tests" the external tools (which perhaps run on a different schedule, or only when you upgrade those tools) which establish your assumptions, passing in the raw input and asserting that you get back the raw output. That way if you upgrade the tool you can catch any behavior changes which may affect you.
You have to decide if those last set of tests are worthwhile or not. It very much depends on the tools involved.

In test driven development, do you write every possible test first, then the code?

In doing test driven development I have been in the habit of writing the first unit test for a new piece of functionality first, then writing the code for that functionality. If I have additional tests to write to cover all scenarios, I usually write them after the code is written. Is this considered bad form? Should I try and write every conceivable test for a piece of functionality first, before ever writing that code?
In order to do TDD properly, you always write the test first, and then the functionality second.
To add to that, I would take one scenario at a time, don't write 20 tests and then write the code for those 20 tests. Write one test, red/green flag it, then move on to your next test. This makes sure you're also doing one of the core tenets of TDD, which is to do the simplest implementation possible that meets all of your requirements/scenarios.
actually no, I often discover functionality "on-the-go". Let me explain the "no" a bit further:
I usually start out writing a test case for a high level feature, defining its Interface. After that, I usually set this test to ignore and continue writing tests for each of the Interfaces functionality. My cycle goes like:
Integration Test for Story A (high level API)
Write Unit Test for method xyz called in Integration Test
Implement method (red/green/refactor)
Repeat 2+3 till Integration Test passes.
While doing so, I often realize I have forgotten some small functionality in my main test. I then usually take time to look back at my customers requirements. If its a fit, I go back and add a test for it, set to ignored as I first want to finish what I started.
Sometimes I see the chance to do a refactoring. I usually finish an implementation till I reach a commit point and do refactoring then, however sometimes I stash my changes, go back and do the refactoring (including new tests if nescessary) first. This workflow is powererd by Mercurial MQ.
For most people, TDD and incremental/agile development go together. This looks something like:
Write a test for some feature
Write just enough code to make the test pass, refactoring as necessary
Repeat.
If you happen to have a detailed specification ahead of time, you could write all of the tests first, but you'd have to live with having sone tests not passing for a while.
The sooner you write the tests, the better. I usually find writing tests being harder tasks than actually implementing the functionality because you have to be aware of all the possible outcomes. So I tend to write more tests when I'm "in the zone". And when during coding I realize I might have missed a test case I just note that down on the to-do lists.
So in my opinion it's up to your leisure but I would implement tests in multiple batches.
The way I see it, test driven development isn't necessarily tests first development. Your tests drive your development and you are really writing your tests as you develop your application. You start by writing a simple test that fails because you haven't written the functionality yet. Then you write your code to implement that so that the tests pass.
Then you go back to your test, make modifications that will force you to add more functionality or refactor your code to follow better practices or reduce duplicate code, go fix your code to make the test pass...repeat, repeat, repeat.
A couple of videos that demonstrates this is below, although you can probably find a lot more by googling "TDD Video"
http://agilesoftwaredevelopment.com/videos/test-driven-development-basic-tutorial
(oops, only one video, new users can't insert more than one link)
I try to write a test at some level before each bit of functionality. Sometimes, I have to write a little more code to get through the compiler, but I try to minimise that. Writing the test first means that I've thought about what the code is supposed to achieve before writing it.
One technique I find useful is to keep an index card or notepad handy, and make a note of all the cases that I think of along the way. That allows me to focus on the current task without losing track of all the other things I'm supposed to think about. Afterwards, I can work through the list and either complete the extra cases or drop them as not necessary.
You could do that, but you wouldn't be doing TDD. The problem (well, one of them, anyway) with writing all of your tests up front is that in any case where the requirements are non-trivial, your tests will be building in a lot of assumptions about the structure of the code you're test-driving. Big steps lead to missteps.
One of the keys of successful TDD involves taking small steps. Small steps mean fewer changes to back out when something goes wrong. Small steps mean you can more often get your head around the effects of the changes you're making. And because small steps are easier to take with confidence, they have the paradoxical effect of increasing your velocity.
The TDD cycle starts with requirements. Start by choosing a requirement you know how to define through tests immediately, in a few short steps. If you look at a requirement and you're not sure how to test it, or you think, "Yeah, but to do that, I'd need to [insert ill-defined steps] first", then you should either skip to another requirement that you know how to do, or you should break this requirement into smaller requirements that you know how to do.
Once you have that, you work in a short red-green-refactor cycle: Write a test that quantifies some part of the requirement ("red", because it fails, because it has no implementation to test yet), write any code that will pass the test ("green"), then rework the code to remove duplication, magic numbers, and other code smells ("refactor"). During the refactoring phase, you should continue working in small steps, frequently re-running the test to make sure you haven't broken anything. Continue this cycle until you can look your boss/client in the eye and call the requirement met.
Now that you have one simple piece of your system defined, you've opened up the list of requirements available to implement - requirements that are adjacent to or dependent on the one you just implemented can now be tested and implemented in smaller steps building on what you've already done.
So the upshot of all that is: Don't try to do all your tests at once. One (small) thing at a time.
The point of TDD is that you have to observe that test fails when feature is not yet implemented. So you have to write test before code.
When you get into the TDD rhythm you write one test at a time and make it work. Very short red-green-refactor cycles really feel the rhythm. That being said, there is nothing wrong with other approaches (and they may even make more sense for some types of problems) but typically the only thing you need to do about other tests you are thinking of is write them down (or have your pair if you are pair programming write them down) so you don't forget them. You have to do that anyway because you could forget about a test in the middle of writing a different test.
Do just enough tests to test 1 unit of code at a time.. then write the actual code until it passes the test.. rinse, wash, repeat until done.
If you find yourself needing to write many tests for one unit of code ( a method, a function etc) it might be a sign that you are trying to do too much in that unit... which in turn makes the unit dificult to test & to refactor at a later time.

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