If your tests: - run fast (<10s) - run on your local machine - run on your local code (including uncomitted diffs) ... whether they're called "integration"

If your tests: - run fast (<10s) - run on your local machine - run on your local code (including uncomitted diffs) ... whether they're called "integration" or "unit" tests doesn't matter, as they will detect regressions at the earliest possible time. Unit tests might guarantee smaller code search area (because maybe the failing test only executed 1% of the code), but if running "git stash" makes all the tests pass again, I have a pretty good confidence about where the error lies.