improvement: Don't dealias named tuples for type hints

This causes the code to grow quite a lot.

Fixes scalameta/metals#7397

Author: tgodzik

presentation-compiler/src/main/dotty/tools/pc/MetalsInteractive.scala

@@ -206,7 +206,7 @@ object MetalsInteractive:
       // Handle select on named tuples
       case (Apply(Apply(TypeApply(fun, List(t1, t2)), List(ddef)), List(Literal(Constant(i: Int))))) :: _
         if fun.symbol.exists && fun.symbol.name == nme.apply &&
-            fun.symbol.owner.exists && fun.symbol.owner == getModuleIfDefined("scala.NamedTuple").moduleClass =>
+            fun.symbol.owner.exists && fun.symbol.owner == defn.NamedTupleModule.moduleClass =>
         def getIndex(t: Tree): Option[Type] =
           t.tpe.dealias match
             case AppliedType(_, args) => args.get(i)

presentation-compiler/src/main/dotty/tools/pc/PcInlayHintsProvider.scala

@@ -142,7 +142,7 @@ class PcInlayHintsProvider(
       if isInScope(tpe) then tpe
       else tpe.deepDealias(using indexedCtx.ctx)
 
-    val dealiased = optDealias(tpe)
+    val dealiased = if tpe.isNamedTupleType then tpe else optDealias(tpe)
     val tpeStr = printer.tpe(dealiased)
     val usedRenames = printer.getUsedRenames
     val parts = partsFromType(dealiased, usedRenames)

presentation-compiler/test/dotty/tools/pc/tests/inlayHints/InlayHintsSuite.scala

@@ -1055,4 +1055,24 @@ class InlayHintsSuite extends BaseInlayHintsSuite {
          |}
          |""".stripMargin
     )
+
+  @Test def `named-tuples` =
+    check(
+      """|def hello = (path = ".", num = 5)
+         |
+         |def test =
+         |  hello ++ (line = 1)
+         |
+         |@main def bla =
+         |   val x: (path: String, num: Int, line: Int) = test
+         |""".stripMargin,
+      """|def hello/*: (path : String<<java/lang/String#>>, num : Int<<scala/Int#>>)*/ = (path = ".", num = 5)/*[(String<<java/lang/String#>>, Int<<scala/Int#>>)]*/
+         |
+         |def test/*: Concat<<scala/NamedTuple.Concat#>>[(path : String<<java/lang/String#>>, num : Int<<scala/Int#>>), (line : Int<<scala/Int#>>)]*/ =
+         |  hello ++/*[Tuple1<<scala/Tuple1#>>["line"], Tuple1<<scala/Tuple1#>>[Int<<scala/Int#>>]]*/ (line = 1)/*(using refl<<scala/`<:<`.refl().>>)*//*[Tuple1<<scala/Tuple1#>>[Int<<scala/Int#>>]]*/
+         |
+         |@main def bla/*: Unit<<scala/Unit#>>*/ =
+         |   val x: (path: String, num: Int, line: Int) = test
+         |""".stripMargin
+    )
 }