Originally, we though that we would move classes from `ide-common` from Kotlin plugin to this
module but it turns that these classes are heavily used in Kotlin plugin and it's better to
keep them with the rest of Kotlin plugin. So now classes in `scripting-ide-common` are copy-pasted
I want to be able to use this function in `:kotlin-scripting-ide-common` & `frontend-independent`
This commit also allows to remove copy-pasted `findLabelAndCall` in `scripting-ide-services` module
During code completion, ShadowedDeclarationsFilter resolves many
synthetic calls (sometimes >1000 for certain projects/scenarios).
By ignoring diagnostics we can avoid running call checkers
during this process (pending a sibling change in the compiler).
Relates to KT-44276 and github.com/JetBrains/kotlin/pull/4027
If there are multiple copies of the same library on the classpath,
then ShadowedDeclarationsFilter becomes very slow because it
encounters many equal-signature declarations and thus has to resolve
a lot of calls in order to pick among them.
Having multiple copies of the same library on the classpath is
somewhat common in real-world projects. It occurs in the
JetBrains/intellij-kotlin project, for example. In that project,
ShadowedDeclarationsFilter ends up resolving thousands of calls,
accounting for around 80% of completion time when there are
many completion results (see KT-44276).
We can optimize ShadowedDeclarationsFilter by checking whether the
descriptors in an equal-signature group are structurally equivalent.
If they are, we can just pick one rather than running resolve.
Testing on a small project with Kotlin stdlib duplicated on the
classpath, this change reduces overhead in ShadowedDeclarationsFilter
from 1200 ms to 20 ms when running completion on the prefix 'a'.
End-to-end completion time is cut in half.
Test: JvmBasicCompletionTestGenerated.Common.Shadowing
Receiver of a function call '<receiver>.foo()' (where receiver is a
class/object/alias name) might be specified incorrectly - corresponding
[companion] object might not be declared.
Before this commit '<receiver>' was considered to be undefined (null).
As a consequence, import suggestion included all 'foo()' functions from
the search scope.
Now as a value of '<receiver>' we set class/object/alias itself
resulting in an empty import suggestion list.
See org/jetbrains/kotlin/idea/util/CallType.kt:307
(#extractReceiverTypeFrom(descriptor: ClassDescriptor)).
Vladimir Dolzhenko