Regression tests don't usually identify bugs in new features, unless they interact with the older code or required changing the older code. In my experience, they're useful to have, but not useful for identifying novel issues. I recall reading someone's analysis of applying fuzzing and that using a particular fuzzer would eventually stop discovering issues, but that didn't mean the system under test was perfect. It meant that they had worked out most (if not all) the errors that fuzzer could identify for them and needed a new fuzzer.
The same thing with regression testing. I wouldn't stop running regression tests just because they aren't identifying issues anymore, but I wouldn't rely on them to discover novel issues. That's what the new, updated test suite should be doing. A regression test suite will not have a test to cover a new feature. It will only make sure that the new feature doesn't break the old one.
The same thing with regression testing. I wouldn't stop running regression tests just because they aren't identifying issues anymore, but I wouldn't rely on them to discover novel issues. That's what the new, updated test suite should be doing. A regression test suite will not have a test to cover a new feature. It will only make sure that the new feature doesn't break the old one.
[0] https://blog.regehr.org/archives/1796 - found it