bugfix: workaround for missing span in reference to an extension method defined in the companion object

[kasiaMarek]

Workaround for missing span in:

class MyIntOut(val value: Int)
object MyIntOut:
  extension (i: MyIntOut) def <<uneven>> = i.value % 2 == 1

val a = MyIntOut(1).un@@even

to provide correct:

1. semantic highlighting,
2. highlight,
3. go to definition.

#5630

[jkciesluk]

I think it can also close #5522

The idea looks good, but there is an issue when the method is not simply on ident

[jkciesluk]

This won't work for case mentioned in the comment, because sel.span points to @@MyInt(1).uneven,
so path is Ident :: Apply(MyInt, 1) :: Select :: _.

We can maybe take span from parent and use it? Also, I'm not sure if untyped will be then even needed here

[kasiaMarek]

Which comment? I get it now 😂 .

[jkciesluk]

The one above this case

class MyIntOut(val value: Int)
object MyIntOut:
  extension (i: MyIntOut) def <<uneven>> = i.value % 2 == 1

val a = MyIntOut(1).un@@even

[jkciesluk]

I think for most cases, the span would be the Apply span, from point to end, so we won't have to use untypedPath, but I have to check how it will work for infix methods

[jkciesluk]

I would add a test for hover, besides LGTM

[tgodzik]

LGTM! Does it also fix #5478 ?

[tgodzik]

I think for the presentation compiler, we should actually fix the span, so no need to port this to the compiler most likely. (just tests after the span fix is done)

[kasiaMarek]

I think for the presentation compiler, we should actually fix the span

scala/scala3#18557 😉

[tgodzik]

I think for the presentation compiler, we should actually fix the span

lampepfl/dotty#18557 😉

Och, that's amazing!