chore: backport changes from metals (#19452)

Backports changes from 
- scalameta/metals#5891
- scalameta/metals#5982

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

@@ -36,16 +36,20 @@ object HoverProvider:
     val text = params.text().nn
     val sourceFile = SourceFile.virtual(uri, text)
     driver.run(uri, sourceFile)
+    val unit = driver.compilationUnits.get(uri)
 
-    given ctx: Context = driver.currentCtx
+    given ctx: Context =
+      val ctx = driver.currentCtx
+      unit.map(ctx.fresh.setCompilationUnit).getOrElse(ctx)
     val pos = driver.sourcePosition(params)
-    val trees = driver.openedTrees(uri)
+    val path = unit
+      .map(unit => Interactive.pathTo(unit.tpdTree, pos.span))
+      .getOrElse(Interactive.pathTo(driver.openedTrees(uri), pos))
     val indexedContext = IndexedContext(ctx)
 
     def typeFromPath(path: List[Tree]) =
       if path.isEmpty then NoType else path.head.tpe
 
-    val path = Interactive.pathTo(trees, pos)
     val tp = typeFromPath(path)
     val tpw = tp.widenTermRefExpr
     // For expression we need to find all enclosing applies to get the exact generic type
@@ -72,7 +76,10 @@ object HoverProvider:
               |path:
               |- ${path.map(_.toString()).mkString("\n- ")}
               |trees:
-              |- ${trees.map(_.toString()).mkString("\n- ")}
+              |- ${unit
+               .map(u => List(u.tpdTree))
+               .getOrElse(driver.openedTrees(uri).map(_.tree))
+               .map(_.toString()).mkString("\n- ")}
               |""".stripMargin,
           s"$uri::$posId"
         )
@@ -83,15 +90,9 @@ object HoverProvider:
       val skipCheckOnName =
         !pos.isPoint // don't check isHoveringOnName for RangeHover
 
-      val printerContext =
-        driver.compilationUnits.get(uri) match
-          case Some(unit) =>
-            val newctx =
-              ctx.fresh.setCompilationUnit(unit)
-            Interactive.contextOfPath(enclosing)(using newctx)
-          case None => ctx
+      val printerCtx = Interactive.contextOfPath(path)
       val printer = ShortenedTypePrinter(search, IncludeDefaultParam.Include)(
-        using IndexedContext(printerContext)
+        using IndexedContext(printerCtx)
       )
       MetalsInteractive.enclosingSymbolsWithExpressionType(
         enclosing,
@@ -142,7 +143,8 @@ object HoverProvider:
                   expressionType = Some(expressionType),
                   symbolSignature = Some(hoverString),
                   docstring = Some(docString),
-                  forceExpressionType = forceExpressionType
+                  forceExpressionType = forceExpressionType,
+                  contextInfo = printer.getUsedRenamesInfo
                 )
               ).nn
             case _ =>
@@ -176,6 +178,7 @@ object HoverProvider:
               new ScalaHover(
                 expressionType = Some(tpeString),
                 symbolSignature = Some(s"$valOrDef $name$tpeString"),
+                contextInfo = printer.getUsedRenamesInfo
               )
             )
           case RefinedType(parent, _, _) =>

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

@@ -39,6 +39,8 @@ final class PcSyntheticDecorationsProvider(
   val source =
     SourceFile.virtual(filePath.toString, sourceText)
   driver.run(uri, source)
+
+  given InferredType.Text = InferredType.Text(text)
   given ctx: Context = driver.currentCtx
   val unit = driver.currentCtx.run.nn.units.head
 
@@ -219,11 +221,16 @@ object TypeParameters:
 end TypeParameters
 
 object InferredType:
-  def unapply(tree: Tree)(using Context) =
+  opaque type Text = Array[Char]
+  object Text:
+    def apply(text: Array[Char]): Text = text
+
+  def unapply(tree: Tree)(using text: Text, cxt: Context) =
     tree match
       case vd @ ValDef(_, tpe, _)
           if isValidSpan(tpe.span, vd.nameSpan) &&
-            !vd.symbol.is(Flags.Enum) =>
+            !vd.symbol.is(Flags.Enum) &&
+            !isValDefBind(text, vd) =>
         if vd.symbol == vd.symbol.sourceSymbol then
           Some(tpe.tpe, tpe.sourcePos.withSpan(vd.nameSpan), vd)
         else None
@@ -247,6 +254,14 @@ object InferredType:
       nameSpan.exists &&
       !nameSpan.isZeroExtent
 
+  /* If is left part of val definition bind:
+   * val <<t>> @ ... =
+   */
+  def isValDefBind(text: Text, vd: ValDef)(using Context) =
+    val afterDef = text.drop(vd.nameSpan.end)
+    val index = afterDef.indexAfterSpacesAndComments
+    index >= 0 && index < afterDef.size && afterDef(index) == '@'
+
 end InferredType
 
 case class Synthetics(

presentation-compiler/src/main/dotty/tools/pc/printer/ShortenedTypePrinter.scala

@@ -62,6 +62,13 @@ class ShortenedTypePrinter(
       AbsOverride,
       Lazy
     )
+
+  private val foundRenames = collection.mutable.Map.empty[Symbol, String]
+
+  def getUsedRenamesInfo(using Context): List[String] =
+    foundRenames.map { (from, to) =>
+      s"type $to = ${from.showName}"
+    }.toList
 
   def expressionType(tpw: Type)(using Context): Option[String] =
     tpw match
@@ -117,8 +124,10 @@ class ShortenedTypePrinter(
 
     prefixIterator.flatMap { owner =>
       val prefixAfterRename = ownersAfterRename(owner)
+      val ownerRename = indexedCtx.rename(owner)
+        ownerRename.foreach(rename => foundRenames += owner -> rename)
       val currentRenamesSearchResult =
-        indexedCtx.rename(owner).map(Found(owner, _, prefixAfterRename))
+        ownerRename.map(Found(owner, _, prefixAfterRename))
       lazy val configRenamesSearchResult =
         renameConfigMap.get(owner).map(Missing(owner, _, prefixAfterRename))
       currentRenamesSearchResult orElse configRenamesSearchResult
@@ -181,7 +190,9 @@ class ShortenedTypePrinter(
 
   override protected def selectionString(tp: NamedType): String =
     indexedCtx.rename(tp.symbol) match
-      case Some(value) => value
+      case Some(value) => 
+        foundRenames += tp.symbol -> value
+        value
       case None => super.selectionString(tp)
 
   override def toText(tp: Type): Text =

presentation-compiler/src/main/dotty/tools/pc/utils/MtagsEnrichments.scala

@@ -230,6 +230,34 @@ object MtagsEnrichments extends CommonMtagsEnrichments:
 
     def stripBackticks: String = s.stripPrefix("`").stripSuffix("`")
 
+  extension (text: Array[Char])
+    def indexAfterSpacesAndComments: Int = {
+      var isInComment = false
+      var startedStateChange = false
+      val index = text.indexWhere {
+        case '/' if !isInComment && !startedStateChange =>
+          startedStateChange = true
+          false
+        case '*' if !isInComment && startedStateChange =>
+          startedStateChange = false
+          isInComment = true
+          false
+        case '/' if isInComment && startedStateChange =>
+          startedStateChange = false
+          isInComment = false
+          false
+        case '*' if isInComment && !startedStateChange =>
+          startedStateChange = true
+          false
+        case c if isInComment || c.isSpaceChar || c == '\t' =>
+          startedStateChange = false
+          false
+        case _ => true
+      }
+      if (startedStateChange) index - 1
+      else index
+    }
+
   extension (search: SymbolSearch)
     def symbolDocumentation(symbol: Symbol)(using
         Context

presentation-compiler/test/dotty/tools/pc/tests/decorations/SyntheticDecorationsSuite.scala

@@ -498,3 +498,31 @@ class SyntheticDecorationsSuite extends BaseSyntheticDecorationsSuite:
         |""".stripMargin
     )
 
+  @Test def `val-def-with-bind` = 
+    check(
+      """
+        |object O {
+        |  val tupleBound @ (one, two) = ("1", "2")
+        |}
+        |""".stripMargin,
+      """
+        |object O {
+        |  val tupleBound @ (one: String, two: String) = ("1", "2")
+        |}
+        |""".stripMargin
+    )
+
+  @Test def `val-def-with-bind-and-comment` = 
+    check(
+      """
+        |object O {
+        |  val tupleBound /* comment */ @ (one, two) = ("1", "2")
+        |}
+        |""".stripMargin,
+      """
+        |object O {
+        |  val tupleBound /* comment */ @ (one: String, two: String) = ("1", "2")
+        |}
+        |""".stripMargin
+    )
+

presentation-compiler/test/dotty/tools/pc/tests/edit/InsertInferredTypeSuite.scala

@@ -789,6 +789,28 @@ class InsertInferredTypeSuite extends BaseCodeActionSuite:
          |""".stripMargin
     )
 
+  @Test def `import-rename` =
+    checkEdit(
+      """
+        |package a
+        |import scala.collection.{AbstractMap => AB}
+        |
+        |object Main {
+        |  def test(): AB[Int, String] = ???
+        |  val <<x>> = test()
+        |}
+        |""".stripMargin,
+      """
+        |package a
+        |import scala.collection.{AbstractMap => AB}
+        |
+        |object Main {
+        |  def test(): AB[Int, String] = ???
+        |  val x: AB[Int, String] = test()
+        |}
+        |""".stripMargin
+    )
+
   def checkEdit(
       original: String,
       expected: String

presentation-compiler/test/dotty/tools/pc/tests/hover/HoverDefnSuite.scala

@@ -163,8 +163,7 @@ class HoverDefnSuite extends BaseHoverSuite:
       """package b.p@@kg
         |object Main
         |""".stripMargin,
-      // TODO, doesn's show information on packages
-      ""
+      "package b.pkg".hover,
     )
 
   @Test def `pat-bind` =

presentation-compiler/test/dotty/tools/pc/tests/hover/HoverTermSuite.scala

@@ -419,7 +419,8 @@ class HoverTermSuite extends BaseHoverSuite:
         |object MyIntOut:
         |  extension (i: MyIntOut) def uneven = i.value % 2 == 1
         |
-        |val a = MyIntOut(1).un@@even
+        |object Test:
+        |  val a = MyIntOut(1).un@@even
         |""".stripMargin,
       """extension (i: MyIntOut) def uneven: Boolean
         |""".stripMargin.hover
@@ -593,4 +594,46 @@ class HoverTermSuite extends BaseHoverSuite:
         |extension [A](self: A) def inferredTypeArg[C](value: C): C
         |```
         |""".stripMargin
-    )
+    )
+
+  @Test def `import-rename` =
+    check(
+      """
+        |import scala.collection.{AbstractMap => AB}
+        |import scala.collection.{Set => S}
+        |
+        |object Main {
+        |  def test(): AB[Int, String] = ???
+        |  <<val t@@t = test()>>
+        |}
+        |""".stripMargin,
+      """
+        |```scala
+        |type AB = AbstractMap
+        |```
+        |
+        |```scala
+        |val tt: AB[Int, String]
+        |```""".stripMargin,
+    )
+
+  @Test def `import-rename2` =
+    check(
+      """
+        |import scala.collection.{AbstractMap => AB}
+        |import scala.collection.{Set => S}
+        |
+        |object Main {
+        |  <<def te@@st(d: S[Int], f: S[Char]): AB[Int, String] = ???>>
+        |}
+        |""".stripMargin,
+      """
+        |```scala
+        |type S = Set
+        |type AB = AbstractMap
+        |```
+        |
+        |```scala
+        |def test(d: S[Int], f: S[Char]): AB[Int, String]
+        |```""".stripMargin,
+  )

presentation-compiler/test/dotty/tools/pc/tests/hover/HoverTypeSuite.scala

@@ -362,7 +362,8 @@ class HoverTypeSuite extends BaseHoverSuite:
          |object MyIntOut:
          |  extension (i: MyIntOut) def uneven = i.value % 2 == 1
          |
-         |val a = MyIntOut(1).un@@even
+         |object Test:
+         |  val a = MyIntOut(1).un@@even
          |""".stripMargin,
       """|extension (i: MyIntOut) def uneven: Boolean
          |""".stripMargin.hover,

project/Build.scala

@@ -1341,7 +1341,7 @@ object Build {
       BuildInfoPlugin.buildInfoDefaultSettings
 
   lazy val presentationCompilerSettings = {
-    val mtagsVersion = "1.2.0+54-1a664e80-SNAPSHOT"
+    val mtagsVersion = "1.2.0+67-30f8ab53-SNAPSHOT"
 
     Seq(
       resolvers ++= Resolver.sonatypeOssRepos("snapshots"),