He said that aiming for 100% code-coverage tests in Haskell is pointless, not that unit-testing itself is pointless. Which I think is a pretty reasonable given that a lot of bugs cannot exist by construction in a lot of Haskell code.
Personally I very much enjoy unit-testing in Haskell especially with the new tasty library which makes combining all the Unit/QuickCheck/SmallCheck tests very pleasant.
Indeed. I'm not a fan of 100% code coverage tests in any language, but it's especially apparent in Haskell where, as you said, if code compiles (and you keep most of your functions pure), there are whole classes of bugs that simply cannot exist.
"100% code coverage unit tests is a pointless endeavor"
Thirsteh said 100% coverage of unit tests is pointless, not that unit testing itself is pointless. I'm not totally sure what thirsteh means by "100% is a pointless endeavor" though.
Edit: My bad - I missed the 100% part.