Type in classOf[T] is not added to occurrences in semanticDB

[tgodzik]

object Main{
  val a = classOf[Int]
}

In the example Int symbol will not be added to occurrences. @sswistun-vl is taking a look at it.

[tgodzik]

Should we also add the occurence for classOf ? @olafurpg what do you think?

[olafurpg]

I think we should add occurrences to classOf

[tanishiking]

I looked into this a bit, and I found that we have the following trees for classOf[...].

classOf[Int]

Literal(
  value = Constant(
    value = TypeRef(pre = ThisType(sym = package scala), sym = class Int, args = List())
  )
)

classOf[List[Int]]

Literal(
  value = Constant(
    value = TypeRef(
      pre = SingleType(
        pre = SingleType(pre = ThisType(sym = package <root>), sym = package scala),
        sym = package object scala
      ),
      sym = type List,
      args = List(TypeRef(pre = ThisType(sym = package scala), sym = class Int, args = List()))
    )
  )
)

This is because

• type-checker generate and replace classOf[...] with Literal(Constatnt(...))
  • https://github.com/scala/scala/blob/5cc8ebbd712ca5a0e051a1075af55bc64ad7a2da/src/compiler/scala/tools/nsc/typechecker/Typers.scala#L4312-L4314
  • https://github.com/scala/scala/blob/5cc8ebbd712ca5a0e051a1075af55bc64ad7a2da/src/reflect/scala/reflect/internal/TreeGen.scala#L281-L294
• While it is possible to extract symbols from types, unlike type tree (like AppliedTypeTree) we can't get position information from Types.