Problems with rename refactoring ("F2" in vscode) in the presence of FQN references

[goto40]

I played with a current snapshop of langium (34b3701), roughly langium 0.4.0.
I started the domain model example (as described in the README.md).

Then I get a selection files, containing:

• datatypes.dmodel

    datatype String
    datatype Int
    datatype Decimal
    
    package big {             // <--- rename this (2)
        datatype Int          // <--- rename this (1)
        datatype Decimal
    }
    
    package complex {
        datatype Date
    }
  

• qualified-names.dmodel

     //...      
     package foo.bar {
         datatype Complex
     
         entity E2 extends E1 {
             next: E2
             other: baz.E3
             nested: baz.nested.E5
             time: big.Int                  // <-- observe here
         }
     }
     //...
  

When renaming big.Int (put cursor on Int in package big and press F2) to big.Int2 I get a problem in qualified-names.dmodel: the reference changes to time: Int2 instead of big.Int2):

package foo.bar {
    datatype Complex

    entity E2 extends E1 {
        next: E2
        other: baz.E3
        nested: baz.nested.E5
        time: Int2
    }
}

I also observed when renaming the package big into big2 (in datatypes.dmodel) nothing changes in the file qualified-names.dmodel...

I wonder if we could fix/enhance the (custom) references in order to support such refactoring operations?
(I was motivated by the discussion #615 to try this refactoring)

[msujew]

Hey @goto40, we already have an issue on this, see #236. Someone from our side is taking a look at it in their spare time (see this branch), but it's work in progress.

In general, FQN references pose a general issue to the LSP protocol, since it's main user (vscode) expects every word to be a single reference/value. This isn't the case with FQN, so some special case has to be taken on the language server side in order for these things to work correctly.