unit testing methods with arrays as argument

I am porting over some C++ assembly to VB that performs demodulation of various waveforms. I decided to go the unit test route instead of building a test app to get a feel for how testing is performed. The original demodulation code accepts an array that is the waveform along开发者_StackOverflow社区 with some other arguments. How should one go about performing a test on something that has an array as an argument? Is it acceptable to generate fake data in a file and read it in at the beginning of the test?

On a side note - The original C++ code was written because we were performing math that we couldn't do in VB6 so we had to cross boundaries between C++ and VB6 and arrays were used. Is there a "better" way of handling large amounts of data in the .NET world that us VB6 programmers may not yet be privy to? Or if we aren't crossing that managed/un-managed boundary, should we be representing our data as objects instead?

Thanks all!

Depends on how big the test arrays are. If they are not so big, I would prefer keeping them in the code - this way unit tests are self containing, without dependencies to external resources.

However, if the array is huge, it can be stored in a fake data file. Alternatively, if generation is not very complicated or time consuming, it could even be generated on the fly.

Even if you decide to refactor your API, I recommend to write the unit tests first for the current API. Once you have the tests, you can refactor more safely.

The first thing is to get rid of the arrays. You said in your question the only reason for arrays was for an interface to c++. Now your code is vb.net so clean up that interface. You might originally start with a something that wraps the array: class WaveForm {}. Hide the representational details.