testing code in C C++ [closed]

Answer 1

I generally start out with something about as complicated as MinUnit then build up a set of macros which suits the project I'm working on to suit that project's conventions.

Each component will have an executable which builds and runs the unit tests for that component.

I don't use a debugger as that requires human intervention, so you can't use it for automatic regression. I don't modify the main executable, as that usually involves many components and is quite complicated enough without having lots of macros to switch bits on and off. Creating a new target using make is very easy.

Answer 2

I use boost.test. I moved to it from cppunit, which was good but too java like, this was a problem because junit uses reflection to find and run your tests, since this is not available in c++ you have to use macros to register your tests, in cppunit you have to declare, register and define your tests in three different places. boost.test lets you declare, register and define your test in one statement this is very nice.

My general approach is to TDD new code and try to use unit test judiciously for legacy code. I esp test any code that is different on different platforms to ensure they behave the same and continue to behave the same.

I structure my projects so that every library or executable project also has a unit test project. For executable tests, I include the executable source files (except main) in the test project and add my test in new files. For library tests, I normally just link to the library except when I am testing private parts of dlls then I use the executable approach.

Using CMake enables you to abstract any duplication between source project and test project. Also CTest integrates well with any unit testing framework that package tests in executables. This lets you run all test executables in a solution in one go and reports a summary of the results. It also integrates with a continuous integration framework called CDash.

A note on TDD, a lot of people treat this as Test driven development but it can be Test Driven Design. This is a very good way to focus on agile design, using TDD for designing my software as well as writing it really opened my eyes.

Answer 3

xUnit is a family of unit testing modules. x is replaced by a letter for the language of framework used. The family currently consists of:

• CUnit (for C)
• CppUnit
• NUnit (.NET)
• EmbUnit ; embedded unit test for C

I've worked in projects using CppUnit with good results. Recently I've tried to integrate this in an automatic build environment (i.e. Hudson) and I came across many obstacles.

Ideally, the build automatically builds and runs the unit tests. In that case, code is run from the test environment (and thus has it's own main loop). An extra complication in my case is that I work with embedded systems; printf is not always possible. I expect that if you run on PC, CUnit and CppUnit can help you a lot to implement good unit testing. Please look at how to use the results; a continuous integration system will increase your effiency a lot.

Another framework worth to give a look is Maestra. It relies on C99 (which Microsoft has never implemented, but for gcc it is great!)

Answer 4

The approach of Test Driven Development (TDD) is to first write the test, see that it fails by default (i.e., a new test succeeds by failing), then write the function to pass the test.

In this way, testing becomes not an afterthought, but the very core of your development methodology.

Because you may be developing a function (method) before you have implemented the objects upon which it operates, most TDD frameworks also provide a facility for generating "mock" objects, which will return expected results before their classes are actually implemented.

I personally recommend Google Test and Google Mock.

Answer 5

I use googletest/gtest

Answer 6

I've learnt to love googletest/googlemock. They are a very powerful combination and easy to use. There is also a lot of documentation available on their wiki pages.

googletest: code.google.com/p/googletest/wiki/GoogleTestPrimer

googlemock: code.google.com/p/googlemock/wiki/ForDummies