Question

After doing some work with Ruby, Rails, and RSpec last summer and I learned to TATFT. Now I can’t write code without writing tests first.

I’m taking a programming course in C next year, and I would like to learn to write C test-driven. Is it a good idea (or even possible) to do TDD with C? If so, are there any good testing frameworks compatible with C?

Answer 1

Is it a good idea (or even possible) to do TDD with C?

Yes, it obviously is a good idea, as with other languages. However, due to the procedural nature of the language, it comes with its some more difficulties.

• Static functions quickly get in the way. This can be solved by including the source file under test, or defining a STATIC macro that only means static when compiling the code for production – not unit test

  #if defined(UNIT_TEST) #define STATIC #else #define STATIC static #endif 

• There is no isolation: there is only one global context. With an OO language you can just instantiate one object (or a cluster of collaborating objects) to test it (them), you can also use mock objects. With C, you can, however, override functions just by re-defining them in your unit tests. This works fine on Unix-like systems where the linker invokes the first function he is finding – I’m not sure on Windows.

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If so, are there any good testing frameworks compatible with C?

You can start small with minunit. The learning curve is flat as it only is four macros long.

EDIT: There are two lists of UT frameworks for the C language, that were mentioned in other answers and I didn’t repeat : one on Wikepedia and another one on xprogramming.com.