Add missing span to extension method select

[kasiaMarek]

For:

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

val a = MyIntOut(1).uneven

uneven call in the typed tree has span <126..126>, where it should be <138..144>.

connected to: scalameta/metals#5630

I'm open to suggestions on how to do it nicer.

[dwijnand]

We already a NoSpan "null" object we can use, instead of having to wrap it with Option. Could you switch to that, please? You can then call .exists on the span (which just compares to NoSpan) instead of calling foldLeft (which also creates another lambda).

[dwijnand]

Hi, sorry for not mention this earlier. I thinking now we should try to carry the name span together with the name, in the SelectionProto. If need be, I can try that out myself when I'm back home on Monday.

[tanishiking]

@kasiaMarek Awesome, could you add a test case for SemanticDB that confirms this change fixes #18570 ?

diff --git a/tests/semanticdb/expect/Extension.scala b/tests/semanticdb/expect/Extension.scala
index c204b1ff7f..86d6ec0586 100644
--- a/tests/semanticdb/expect/Extension.scala
+++ b/tests/semanticdb/expect/Extension.scala
@@ -16,3 +16,12 @@ extension (s: String)
 
 trait Functor[F[_]]:
   extension [T](t: F[T]) def map[U](f: T => U): F[U]
+
+opaque type Deck = Long
+object Deck:
+  extension (data: Deck)
+    def fooSize: Int = ???
+
+object DeckUsage:
+  val deck: Deck = ???
+  deck.fooSize
\ No newline at end of file

and run sbt:scala3> scala3-compiler-bootstrapped/test:runMain dotty.tools.dotc.semanticdb.updateExpect.

Now fooSize in DeckUsage has a Symbol Occurrence 👍

[dwijnand]

Very nicely done, thank you. 1 diff question left

[kasiaMarek]

Awesome, could you add a test case for SemanticDB that confirms this change fixes #18570 ?

done