It is possible to use rspec-mocks with Minitest as well. Here’s how.
The Relish documentation for rspec-mocks
shows how to integrate with Minitest.
Those instructions work and that’s where you should start. If you
MinitestRSpecMocksIntegration module as outlined in the
documentation, you should be (almost) good to go.
If you don’t want this module included in all of your test cases, you can leave out the last line and instead include the module in only the test case subclasses where it’s needed.
Even with this setup in place, I ran into
one issue trying to
use the spy API of rspec-mocks, specifically the
matcher. The rspec-mocks version of the
expect method is not as
full-featured as the version in rspec-expectations and doesn’t work
There will be a fix for this issue in rspec-mocks 3.4, but that version has not yet been released at the time of this writing.
For rspec-mocks 3.3.x and earlier, there is a workaround. You need to
use rspec-expectations along with rspec-mocks. If you change your
MinitestRSpecMocksIntegration module as follows, the
matcher will work properly.
Note that I don’t use Minitest’s spec syntax. There may be other issues to address if you do.
Thanks to Myron Marston for responding to this issue so quickly, and for committing an excellent fix for it.
If you’d rather use a different mocking framework with Minitest, there are a few other options:
Minitest comes with its own test double framework. It has the basic functionality, but I could never quite get used to it.
FlexMock was originally developed by Jim Weirich (RIP). I’ve used it in the past and was pretty happy with it, but it stopped working with newer versions of Ruby. Since then, Sylvain Joyeux has stepped up as the new maintainer of FlexMock and fixed the issues I ran into. Thanks for taking this on, Sylvain!
Mocha seems like a pretty complete test double library, and a lot of people use it. I don’t have any first-hand experience with it, but it is definitely a viable option.