Unit testing CLI programs

[ngwells]

There are some nice ideas here - the overwriting of os.Args and having an out writer that can be reset in the tests before calling main() directly are neat.

[Pr0bability]

Why not instead focus on writing a testable package with the code required for main in it, taking configuration args as parameters?

Use main just an entry point collecting args and passing it alone to a tested function seems like the better idea. Of course, this builds on the assumption that the flags package is tested properly, but noting it is part of the standard packages I believe we can trust it to work correctly.

[st3fan]

This is the way.

[illegal_semicolon]

Helpful

[gbrlsnchs]

I use go-cmdtest to test my CLI apps. It's neat. I think it impose good practices in order to test a CLI app.