In case Java enum has an abstract member, it has the ACC_ABSTRACT flag
set in the bytecode. However, we should still load it with final
modality to be consistent with Kotlin enums which are always considered
final
#KT-23426 Fixed
Since we skipped trivial constraint with `Any?` from parameter type of
function `equals`, the compiler thought that there is no proper
constraints (upper bounds do not matter here) and marked resolved
call as a failed one, then diagnostic about missing equals was added
Also, tune `TrivialConstraintTypeInferenceOracle` for `Any?`-like
constraints
#KT-30724 Fixed
The problem is that delegated properties resolve two calls together:
`getValue`/`setValue` with a common receiver, which can contain
callable references. For each completion new anonymous descriptor
was created and caused "rewrite at slice" exceptions later.
Now there is a little hack to check that during one inference session
we don't complete one call more than one time.
More correct fix would be to explicitly specify common receiver for
inference session but it requires quite big refactoring, which will
be done later with a whole refactoring of the common solver
#KT-30250 Fixed
Consider common supertype of `S` and `Nothing`, where `S` has nullable
upper bound or it's flexible. Before the fix, result was `S?`, which
is correct but too conservative. Now, we'll preserve nullability of
resulting type if it's already nullable.
This happened because we were failing to find path of not-nullable
types from `Nothing` to `S`, which should obviously exists by
semantics of Nothing
Input and output types are crucial for type variable fixation order and
analysis of postponed arguments (callable references, lambdas).
Specifically, if there is non-fixed type variable inside input types of
a callable reference, then we'll postpone resolution for such callable
reference.
Initial example with the expected type `KMutableProperty1<*, F>` caused
problems because input types were computed incorrectly (while there
aren't input types here)
#KT-25431 Fixed
It's needed to estimate the count of steps for type approximation algorithm.
After the estimated count of steps, we consider such type recursive and this
algorithm returns some default value
#KT-28598 Fixed