We have our own test automation software which executes our product exe. We do not have test cases written in C++ but our code is written in C++.
What we want is to run out automation tool on our exe which will run the test suite and then find the lines of code that have been executed (code-coverage).
Is there any way to do the above? Something similar to LCOV?
Semantic Designs' (my company) C++ Test Coverage Tool could be used for this for either MS C++ or GCC.
The tool instruments your source code before you compile it. The compiled binary is executed by whatever means; as it runs, the instrumentation collects test coverage information, and occasionally writes that data to a special file. That file is then analyzed/displayed by a special UI.
If you can get your automation tool to signal when an individual test is complete (this may happen as a natural "last action" on each test, or by other convention), then the test coverage data can be captured on a per-test basis to give you a finer-grain view of the coverage data.
We are just about to start a new project. The Proof of Concept (PoC) for this project was done simply using Win32. The plan is/was to flesh out the PoC, tidy the uglier parts and meet the requirements set by the project owners.
One of the requirements for the actual project is 100% code coverage but I can see problems ahead: How can I acheive 100% code coverage with Win32 - the message pump will be exceptionally difficult to test effectively?! I could compile to a DLL but won't there be code in the main app that won't be under coverage?
I am thinking of dropping the Win32 code and moving to MFC - at least then a lot of the boiler plate stuff will be hidden from view (and therefore coverage).
Any thoughts on the problem?
I mean WndProc, but the same applies for WinMain. How can you unit-test that?
I do testing but not unit-testing: I do system/integration testing.
If you exercise your (whole) application while it's running under a debugger/profiler/code coverage analyser, then of course you will find (and the coverage analyser will show) that WinMain etc. are being run (are being covered).
The question then might be, how do you automate the system/integration testing of the whole application? You might have a test framework with automates driving the GUI; I don't know of any myself, but for example there's a list here. Alternatively, it might be acceptable (to the client) if the acceptance test suite is a sequence of non-automated/manual tests.
See also Should one test internal implementation, or only test public behaviour?
I am attempting add some tests to an existing QT GUI application using QTest. The GUI uses quite a bit of complicated start-up code so I'd rather not write another main() to start it again.
To me, it seems like the easiest way would be instantiate the app and then run the tests on it. I am just not sure, however what function I could plug my test object into so that I don't block the flow of messages.
I could send a special message to start the test or set a timer but that's complicated and tests are supposed to simplify things.
So where would be the best place in existing GUI to insert and qexec a Qtest object?
I'm willing to be proven wrong, but test frameworks in general (and QTest specifically from what I've used of it) tend to assume that the test framework will be driving the code to be tested, as opposed to running along side of it.
I'm also concerned about "The GUI uses quite a bit of complicated start-up code...." Are you intending on testing the startup code? Or testing other stuff around it?
Generally speaking, when I start looking at adding tests to an application, I try to find smaller pieces that are used in a lot of the application, and write tests for those. I then build up to testing the bigger pieces that integrate those smaller ones. My general idea is that if the small pieces work properly, then either I've put them together correctly and things should work, or I haven't and things should obviously fail when I try to run the application.
I should mention that there are other options for testing GUIs for Qt applications in particular. They tend to be more like scripts run on your program, with the output recorded. If that interests you, then you could look into Squish for Qt.
I have noticed that if I have a set of regression tests and decide to change a property on one of my objects (DTO) from int to decimal for example - i make all the other changes and the tests pass like normal. But if this project is under source control (VSS specifically) this small change will cause something strange to happen...
Similar to this question
Testing in Visual Studio Succeeds Individually, Fails in a Set
But a little different. I can make this change, and try to run my tests and any test that has an assert around this new data type will fail, but if I then click "debug checked tests" and it then runs through the previously failed tests - they pass. No changes to the test code /etc
Does anyone know why this might be happening? I hate to work outside of source control but if my tests are not reliable ... why have them at all in this case ... and I live for testing code :P
Given the age of the question, I doubt it's still an issue for you, but I wonder if you have a bin or obj folders under source control or an assembly that is in them?
If they are then when you compile the app (before MSTest runs) the source controlled assemblies are going to be in read-only mode and won't get overridden by the compiler and thus your tests will be against out of date binaries.
As I am coding my unit tests, I tend to find that I insert the following lines:
Console.WriteLine("Starting InteropApplication, with runInBackground set to true...");
try
{
InteropApplication application = new InteropApplication(true);
application.Start();
Console.WriteLine("Application started correctly");
}
catch(Exception e)
{
Assert.Fail(string.Format("InteropApplication failed to start: {0}", e.ToString()));
}
//test code continues ...
All of my tests are pretty much the same thing. They are displaying information as to why they failed, or they are displaying information about what they are doing. I haven't had any formal methods of how unit tests should be coded. Should they be displaying information as to what they are doing? Or should the tests be silent and not display any information at all as to what they are doing, and only display failure messages?
NOTE: The language is C#, but I don't care about a language specific answer.
I'm not sure why you would do that - if your unit test is named well, you already know what it's doing. If it fails, you know what test failed (and what assert failed). If it didn't fail you know that it succeeded.
This seems completely subjective, but to me this seems like completely redundant information that just adds noise.
I personally would recommend that you output only errors and a summary of the number of tests run and how many passed. This is a completely subjective view though. Display what suits your needs.
I recommend against it - I think that the unit testing should work on the Unix tools philosophy - don't say anything when things are going well.
I find that constructing tests to give meaningful information when they fail is best - that way you get nice short output when things work and it's easy to see what went wrong when there are problems - errors aren't lost to scroll blindness.
I would actually suggest against it (though not militantly). It couples the user interface of your tests with the test implementation (what if the tests are run through GUI viewer?). As alternative I would suggest one of the following:
I'm not familiar with NUnit, but PyUnit allows you to add a description of the test and when tests are run with the verbose option the description is printed. I would look into the NUnit documentation to see if this is something you can do.
Extend the TestCase class that you're inheriting from to add a function from which you call that logs what the test is trying to do. That way different implementations can handle messages in different ways.
I'd say you should output whatever suits your needs, but showing too much can dilute output from test runner.
BTW, your example code hardly looks as a unit test, more of a integration/system test.
I like to buffer the verbose log (about last 20 lines or so), but I don't display it until it gets to some error. When the error happens, it's nice to have some context.
OTOH, unit tests should be small pieces of unrelated code with specific input and output requirements. In most cases, displaying input that caused the error (i.e. wrong output) is enough to trace the problem to its roots.
This might be a bit too language specific, but when I'm writing NUnit tests I tend to do this, only I use the System.Diagnostics.Trace library instead of the console, that way the information is only shown if I decide to watch the tracing.
You don't need to, if the tests are running silently then that means there was no error. There is usually no reason for tests to give any output other than if the test failed. If it's running, then it is running indicated by the test runner that the test has passed, i.e. it is "green". Running the test (together with many tests with console output) through a test runner in an IDE, you'll be spamming the console log with messages nobody will care about.
The test you've written is not a unit test, but looks more like an integration/system test because you seem to be running an application as a whole. A unit test will test a public method in a class, preferably keeping the class as isolated as possible.
Using console i/o kinda defies the whole purpose of a unit testing framework. you might as well code the whole test manually. If you are using a unit testing framework, your tests should be very malleable, tied to as few things as possible
Displaying information can be useful; if you're trying to find out why a test failed, it can be useful to be able to see more than just a stack trace, and what happened before the program reached the point where it failed.
However, in the "normal" case where everything succeeds, these messages are unnecessary clutter that distract from what you're really trying to do - ie. looking at an overview of which tests succeeded and failed.
I'd suggest redirecting your debugging messages to a log file. You can either do this by writing all your log message code to call a special "log print" function, or if you're writing a console program, you should be able to redirect stdout to a different file (I know for a fact that you can do this in both Unix and Windows). This way, you get the high level overview but the details are there if you need them.
I would avoid putting extra Try/Catch statements in Unit Tests. First of all, an expected exception in a unit test will already cause the test to Fail. That is the default behavior of NUnit. Essentitally, the test harness wraps each call to your test functions with that code already. Also, by just using the e.ToString() to display what happened, I believe you are losing a lot of information. By default, I believe NUnit will display not just the Exception type, but also the Call Stack, which I don't believe you're seeing with your method.
Secondly, there are times when its necessary. For instance, you can use the [ExpectedException] attribute to actually say when it occurs. Just be sure that when you test non-exception related Asserts (for instance Asserting a list count > 0, etc) that you put in a good description as the argument to the assert. That is useful.
Everything else is generally not needed. If your unit tests are so large that you start putting in WriteLines with what "step" of the test you're on, that is generally a sign that your test should really be broken out into multiple smaller tests. In other words, that you're not doing a unit test, but rather an integration test.
Have you looked at the xUnit style of unit test frameworks?
See Ron Jeffries site for a rather large list.
One of the principles of these frameworks is that they produce little or no output during the test run and only really an indicator of success at the end. In the case of failures its possible to get a more descriptive output of the reason for failure.
The reason for this mode is that while everything is OK you don't want to be bothered by extra output, and certainly if there is a failure you don't want to miss it because of the noise of other output.
Well, you should only know when a test failed and why it failed. It's no use to know what's going on, unless, for example, you have a loop and you want to know exactly where in the loop the test died.
I think your making far more work for yourself. The tests either pass or fail, the failure should hopefully be the exception to the rule and you should let the unit test runner handle and throw the exception. What you're doing is adding cruft, the exception logged by the test runner will tell you the same thing.
The only time I would display what's happening is if there was some aspect of it that would be easier to test non-automatically. For example, if you've got code that takes a little while to run, and might get stuck in an infinite loop, you might want to print out a message every so often to indicate that it is still making progress.
Always make sure failure messages clearly stand out from other output, however.
You could have written the test method like this. It's up to your code-nose which style of test you prefer. I prefer not writing extra try-catches and Console.WriteLines.
public void TestApplicationStart()
{
InteropApplication application = new InteropApplication(true);
application.Start();
}
Test frameworks that I have worked with would interpret any unhandled (and unexpected) exception as a failed test.
Think about the time you took to gold-plate this test and how many more meaningful tests you could have written with that time.