[amikazmi]

1. If you dob't have tests covering code, sure type checks are better than nothing. but if you do, why do you also need type checks?

2. If the tests must be updated whenever the underlying implementation changes it might be testing too much- it's better to test behaviour, not implementation.

[eyelidlessness]

I was addressing the above comments about tests that specifically check types. My position is that declarative types and a type checker are better because each code path is checked automatically without writing additional tests, and because the type checker automatically adapts without changing or writing new tests when the implementation changes. Testing behavior is another thing entirely.