[Scala3] Weird document highlighting in particular function in dotty repo

[dos65]

Steps to reproduce the behavior:

1. open the dotty repo in Metals
2. open compiler/src/dotty/tools/dotc/ast/Desugar.scala
3. put a cursor on any line in def classDef method body
4. notice that full body is highlighted

• Operating system: Linux
• Editor: Visual Studio Code
• Metals version: v0.10.5

[tanishiking]

Looks like this happens when cursor on { ... }.method().

Actually, if we remove .showing at the end of the classDef method, it works fine.

--- a/compiler/src/dotty/tools/dotc/ast/Desugar.scala
+++ b/compiler/src/dotty/tools/dotc/ast/Desugar.scala
@@ -824,7 +824,7 @@ object desugar {
     }

     flatTree(cdef1 :: companions ::: implicitWrappers ::: enumScaffolding)
-  }.showing(i"desugared: $result", Printers.desugar)
+  }

   /** Expand
    *

[dos65]

@tanishiking I thought about that. However, I couldn't reproduce the similar thing on smaller samples. For example, if I add an method with a similar structure in this file it works well and provides correct highlithing

[tgodzik]

It seems that we are getting a wrong range maybe?

[ckipp01]

Related to this, I noticed that when this happens and you see usage of showing like in the above example, code navigation is also impacted. For example trying to goto a definition of a symbol inside of that block ends up leading you to showing instead.

[tgodzik]

Looks like this is working correctly now :tada:

[ckipp01]

Looks like this is working correctly now 🎉

I actually just tested the case I have above and I'm still getting the same issues. Using 0.11.9+90-31235494-SNAPSHOT if I am in the Dotty codebase and trigger a goto definition on isEnum as you see in the gif, I am still brought to showing.

https://github.com/lampepfl/dotty/blob/bf808b380859dc67bef397334f773015c17772f7/compiler/src/dotty/tools/dotc/ast/Desugar.scala#L529

[tgodzik]

Ach damn, the highlighting got fixed because we now use the compiler, but it seemed to me that it was working for go to definition also :/