The changes introduced 471134d31e are only needed
for the case of HMPP project while for other cases it might break the behavior
a bit like in KT-34027
See org.jetbrains.kotlin.resolve.calls.results.OverloadingConflictResolver#filterOutEquivalentCalls
Before 471134d we were comparing
"fun foo(x: String)" with "[substituted] fun foo(x: String)"
and areCallableDescriptorsEquivalent returned false for such case.
Thus, both overrides were left in the resulting set.
After 471134d, those two descriptors
becamed considered as equal thus having a possibility to remove any of them.
The problem is that "areCallableDescriptorsEquivalent" has kind of
unclear contract. Effectively it checks whether two descriptors match
to the same declaration
But straightforward fixing of this exact call-site (using original descriptors)
doesn't help: behavior might change in a very subtle way (see org.jetbrains.kotlin.spec.checkers.DiagnosticsTestSpecGenerated.NotLinked.Dfa.Pos#test72)
So, the main idea is changing the contract for areCallableDescriptorsEquivalent
only when project is HMPP one.
^KT-34027 In Progress
The actual problem was introduced in 4f1e85b468, note how `hashCode` is implemented:
```
var currentHashCode = cachedHashCode
if (currentHashCode == 0) return currentHashCode
...
```
It's a silly bug, there should be check `if (currentHashCode != 0) ...` because `0` is used a marker for "uncomputed value".
Now, in the commit 0219b86d06 I added map with `KotlinType` as a key and because of constant `hash` for `KotlinType`, we basically got `List` instead of `Map`, which caused this performance regression
#KT-34063 Fixed
For compiled scripts there is AbstractIdeCompiledLightClassTest
For now there is a difference in light classes constructed from source and from compiled class (missing baseClass and constructor parameter for script class)
But it doesn't affect users because calling script class from Java isn't supported yet
testData for AbstractIdeLightClassTest and AbstractIdeLightClassForScriptTest can be merged when the difference will be fixed
Denis Zharkov