> I advocate "default to integration testing for application functionality". Those focused on unit tests often mock exactly the things most likely to break: integration points between systems. "Unit" tests of systems are often really verbose, prescriptive about internal state, and worst of all don't catch the bits that actually break.

You're writing this as a comment to an article that explains exactly how to write unit tests that aren't brittle and avoid mocking.

"Only integration tests" vs. "brittle unit tests" is a false dichotomy.