There's a heuristic for approximation of a captured type that once
it has non-trivial lower bound (other than Nothing), it's worth
approximating it to sub-type even while the containing
top-level type is being approximated to super-type.
And that sounds reasonable in case the lower bound is indeed non-trivial,
but that's not the case because nullability here comes from
the nullability of captured type position.
So, the fix is basically not to treat such approximations as non-trivial.
And while that seems to be a bit of a change in the language semantics,
it still looks reasonable (see other changes in test data and KT-58087)
^KT-57958 Fixed
^KT-58087 Fixed
Denis.Zharkov
6651e6ed8c