Sometimes I look over the options and constraints to choose something suboptimal. I have to pick the least-bad solution.
I recently chose a least-bad way to write a test. In a Rails app, the most sensible thing to solve my problem was something like this:
[code lang=text] def propagate_from_child_to_parent model_parents.find_each(&:do_a_sideeffect) end [/code]
In the test, I ended up having to write this assertion
[code lang=text] expect_any_instance_of(ModelParents).to receive(:do_a_sideeffect) [/code]
This kind of stub and assertion is clearly a smell. But, consider the alternatives:
- stub out the child model object under so that
find_eachreturns a stub object that I can make suredo_a_sideffectis called on - try to hack around ActiveRecords associations so it returns the same object as I inject in my test
- seek out some other result of
do_a_sideeffectthat I could assert on
In the end, it felt like the shady mock+assertion was the best choice. Using that particular assertion says “slow down and pay attention, a special thing is happening here”. It’s not something I want to do every time, but it was the least bad solution in this context.
