ScalaDoc : type parameter in extension method is wrong

fixes #12813

scaladoc-testcases/src/tests/extensionParams.scala

@@ -0,0 +1,22 @@
+package tests.extensionParams
+
+extension [A](thiz: A)
+  def toTuple2[B](that: B): (A, B) = thiz -> that
+
+extension [A](a: A)(using Int)
+  def f[B](b: B): (A, B) = ???
+
+extension [A](a: A)(using Int)
+  def ff(b: A): (A, A) = ???
+
+extension [A](a: A)(using Int)
+  def fff(using String)(b: A): (A, A) = ???
+
+extension (a: Char)(using Int)
+  def ffff(using String)(b: Int): Unit = ???
+
+extension (a: Char)(using Int)
+  def fffff[B](using String)(b: B): Unit = ???
+
+extension [A <: List[Char]](a: A)(using Int)
+  def ffffff[B](b: B): (A, B) = ???

scaladoc/src/dotty/tools/scaladoc/api.scala

@@ -41,12 +41,12 @@ enum Modifier(val name: String, val prefix: Boolean):
   case Opaque extends Modifier("opaque", true)
   case Open extends Modifier("open", true)
 
-case class ExtensionTarget(name: String, signature: Signature, dri: DRI, position: Long)
+case class ExtensionTarget(name: String, typeParams: Seq[TypeParameter], argsLists: Seq[ParametersList], signature: Signature, dri: DRI, position: Long)
 case class ImplicitConversion(from: DRI, to: DRI)
 trait ImplicitConversionProvider { def conversion: Option[ImplicitConversion] }
 trait Classlike
 
-enum Kind(val name: String){
+enum Kind(val name: String):
   case RootPackage extends Kind("")
   case Package extends Kind("package")
   case Class(typeParams: Seq[TypeParameter], argsLists: Seq[ParametersList])
@@ -70,7 +70,6 @@ enum Kind(val name: String){
   case Implicit(kind: Kind.Def | Kind.Val.type, conversion: Option[ImplicitConversion])
     extends Kind(kind.name)  with ImplicitConversionProvider
   case Unknown extends Kind("Unknown")
-}
 
 enum Origin:
   case ImplicitlyAddedBy(name: String, dri: DRI)

scaladoc/src/dotty/tools/scaladoc/renderers/MemberRenderer.scala

@@ -280,7 +280,14 @@ class MemberRenderer(signatureRenderer: SignatureRenderer)(using DocContext) ext
         case _ => None
       }.collect {
         case (Some(on), members) =>
-          val sig = Signature(s"extension (${on.name}: ") ++ on.signature ++ Signature(")")
+          val typeSig = InlineSignatureBuilder()
+            .text("extension ")
+            .generics(on.typeParams)
+            .asInstanceOf[InlineSignatureBuilder].names.reverse
+          val argsSig = InlineSignatureBuilder()
+            .functionParameters(on.argsLists)
+            .asInstanceOf[InlineSignatureBuilder].names.reverse
+          val sig = typeSig ++ Signature(s"(${on.name}: ") ++ on.signature ++ Signature(")") ++ argsSig
           MGroup(span(sig.map(renderElement)), members.sortBy(_.name).toSeq, on.name)
       }.toSeq
 

scaladoc/src/dotty/tools/scaladoc/tasty/ClassLikeSupport.scala

@@ -176,7 +176,7 @@ trait ClassLikeSupport:
             val sgn = Inkuire.ExternalSignature(
               signature = Inkuire.Signature(
                 receiver = receiver,
-                arguments = methodSymbol.nonExtensionParamLists.collect {
+                arguments = methodSymbol.nonExtensionTermParamLists.collect {
                   case tpc@TermParamClause(params) if !tpc.isImplicit && !tpc.isGiven => params //TODO [Inkuire] Implicit parameters
                 }.flatten.map(_.tpt.asInkuire(vars)),
                 result = defdef.returnTpt.asInkuire(vars),
@@ -242,11 +242,18 @@ trait ClassLikeSupport:
   private def isDocumentableExtension(s: Symbol) =
     !s.isHiddenByVisibility && !s.isSyntheticFunc && s.isExtensionMethod
 
-  private def parseMember(c: ClassDef)(s: Tree): Option[Member] = processTreeOpt(s)(s match
+  private def parseMember(c: ClassDef)(s: Tree): Option[Member] = processTreeOpt(s) { s match
       case dd: DefDef if isDocumentableExtension(dd.symbol) =>
         dd.symbol.extendedSymbol.map { extSym =>
+          val memberInfo = unwrapMemberInfo(c, dd.symbol)
+          val typeParams = dd.symbol.extendedTypeParams.map(mkTypeArgument(_, memberInfo.genericTypes))
+          val termParams = dd.symbol.extendedTermParamLists.zipWithIndex.map { case (paramList, index) =>
+            ParametersList(paramList.params.map(mkParameter(_, memberInfo = memberInfo.paramLists(index))), paramListModifier(paramList.params))
+          }
           val target = ExtensionTarget(
             extSym.symbol.normalizedName,
+            typeParams,
+            termParams,
             extSym.tpt.asSignature,
             extSym.tpt.symbol.dri,
             extSym.symbol.pos.get.start
@@ -302,7 +309,7 @@ trait ClassLikeSupport:
         Some(parseClasslike(c))
 
       case _ => None
-  )
+  }
 
   private def parseGivenClasslike(c: ClassDef): Member = {
     val parsedClasslike = parseClasslike(c)
@@ -470,8 +477,8 @@ trait ClassLikeSupport:
       specificKind: (Kind.Def => Kind) = identity
     ): Member =
     val method = methodSymbol.tree.asInstanceOf[DefDef]
-    val paramLists: List[TermParamClause] = methodSymbol.nonExtensionParamLists
-    val genericTypes = if (methodSymbol.isClassConstructor) Nil else method.leadingTypeParams
+    val paramLists: List[TermParamClause] = methodSymbol.nonExtensionTermParamLists
+    val genericTypes: List[TypeDef] = if (methodSymbol.isClassConstructor) Nil else methodSymbol.nonExtensionLeadingTypeParams
 
     val memberInfo = unwrapMemberInfo(c, methodSymbol)
 

scaladoc/src/dotty/tools/scaladoc/tasty/SymOps.scala

@@ -141,14 +141,52 @@ object SymOps:
         else termParamss(1).params(0)
       }
 
-    def nonExtensionParamLists: List[reflect.TermParamClause] =
+    def extendedTypeParams: List[reflect.TypeDef] =
+      import reflect.*
+      val method = sym.tree.asInstanceOf[DefDef]
+      method.leadingTypeParams
+
+    def extendedTermParamLists: List[reflect.TermParamClause] =
+      import reflect.*
+      if sym.nonExtensionLeadingTypeParams.nonEmpty then
+        sym.nonExtensionParamLists.takeWhile {
+          case _: TypeParamClause => false
+          case _ => true
+        }.collect {
+          case tpc: TermParamClause => tpc
+        }
+      else
+        List.empty
+
+    def nonExtensionTermParamLists: List[reflect.TermParamClause] =
+      import reflect.*
+      if sym.nonExtensionLeadingTypeParams.nonEmpty then
+        sym.nonExtensionParamLists.dropWhile {
+          case _: TypeParamClause => false
+          case _ => true
+        }.drop(1).collect {
+          case tpc: TermParamClause => tpc
+        }
+      else
+        sym.nonExtensionParamLists.collect {
+          case tpc: TermParamClause => tpc
+        }
+
+    def nonExtensionParamLists: List[reflect.ParamClause] =
       import reflect.*
       val method = sym.tree.asInstanceOf[DefDef]
       if sym.isExtensionMethod then
-        val params = method.termParamss
-        if sym.isLeftAssoc || params.size == 1 then params.tail
-        else params.head :: params.tail.drop(1)
-      else method.termParamss
+        val params = method.paramss
+        val toDrop = if method.leadingTypeParams.nonEmpty then 2 else 1
+        if sym.isLeftAssoc || params.size == 1 then params.drop(toDrop)
+        else params.head :: params.tail.drop(toDrop)
+      else method.paramss
+
+    def nonExtensionLeadingTypeParams: List[reflect.TypeDef] =
+      import reflect.*
+      sym.nonExtensionParamLists.collectFirst {
+        case TypeParamClause(params) => params
+      }.toList.flatten
 
   end extension
 

scaladoc/src/dotty/tools/scaladoc/transformers/ImplicitMembersExtensionTransformer.scala

@@ -26,7 +26,7 @@ class ImplicitMembersExtensionTransformer(using DocContext) extends(Module => Mo
 
       val MyDri = c.dri
       def collectApplicableMembers(source: Member): Seq[Member] = source.members.flatMap {
-        case m @ Member(_, _, _, Kind.Extension(ExtensionTarget(_, _, MyDri, _), _), Origin.RegularlyDefined) =>
+        case m @ Member(_, _, _, Kind.Extension(ExtensionTarget(_, _, _, _, MyDri, _), _), Origin.RegularlyDefined) =>
           val kind = m.kind match
             case d: Kind.Def => d
             case _ => Kind.Def(Nil, Nil)

scaladoc/src/dotty/tools/scaladoc/translators/ScalaSignatureUtils.scala

@@ -24,74 +24,74 @@ trait SignatureBuilder extends ScalaSignatureUtils {
   def memberName(name: String, dri: DRI) = text(name)
 
   def list[E](
-      elements: Seq[E],
-      prefix: String = "",
-      suffix: String = "",
-      separator: String = ", ",
-    )(
-      elemOp: (SignatureBuilder, E) => SignatureBuilder
-    ): SignatureBuilder = elements match {
-      case Nil => this
-      case head :: tail =>
-        tail.foldLeft(elemOp(text(prefix), head))((b, e) => elemOp(b.text(separator), e)).text(suffix)
-    }
+    elements: Seq[E],
+    prefix: String = "",
+    suffix: String = "",
+    separator: String = ", ",
+  )(
+    elemOp: (SignatureBuilder, E) => SignatureBuilder
+  ): SignatureBuilder = elements match {
+    case Nil => this
+    case head :: tail =>
+      tail.foldLeft(elemOp(text(prefix), head))((b, e) => elemOp(b.text(separator), e)).text(suffix)
+  }
 
   def annotationsBlock(d: Member): SignatureBuilder =
-      d.annotations.foldLeft(this){ (bdr, annotation) => bdr.buildAnnotation(annotation)}
-
-    def annotationsInline(d: Parameter): SignatureBuilder =
-        d.annotations.foldLeft(this){ (bdr, annotation) => bdr.buildAnnotation(annotation) }
+    d.annotations.foldLeft(this){ (bdr, annotation) => bdr.buildAnnotation(annotation)}
 
-    def annotationsInline(t: TypeParameter): SignatureBuilder =
-        t.annotations.foldLeft(this){ (bdr, annotation) => bdr.buildAnnotation(annotation) }
+  def annotationsInline(d: Parameter): SignatureBuilder =
+    d.annotations.foldLeft(this){ (bdr, annotation) => bdr.buildAnnotation(annotation) }
 
-    private def buildAnnotation(a: Annotation): SignatureBuilder =
-       text("@").driLink(a.dri.location.split('.').last, a.dri).buildAnnotationParams(a).text(" ")
+  def annotationsInline(t: TypeParameter): SignatureBuilder =
+    t.annotations.foldLeft(this){ (bdr, annotation) => bdr.buildAnnotation(annotation) }
 
-    private def buildAnnotationParams(a: Annotation): SignatureBuilder =
-      if !a.params.isEmpty then
-        val params = a.params.filterNot {
-          case Annotation.LinkParameter(_, _, text) => text == "_"
-          case _ => false
-        }
-        list(params, "(", ")", ", "){ (bdr, param) => bdr.buildAnnotationParameter(param)}
-      else this
+  private def buildAnnotation(a: Annotation): SignatureBuilder =
+    text("@").driLink(a.dri.location.split('.').last, a.dri).buildAnnotationParams(a).text(" ")
 
-    private def addParameterName(txt: Option[String]): SignatureBuilder = txt match {
-        case Some(name) => this.text(s"$name = ")
-        case _ => this
+  private def buildAnnotationParams(a: Annotation): SignatureBuilder =
+    if !a.params.isEmpty then
+      val params = a.params.filterNot {
+        case Annotation.LinkParameter(_, _, text) => text == "_"
+        case _ => false
       }
+      list(params, "(", ")", ", "){ (bdr, param) => bdr.buildAnnotationParameter(param)}
+    else this
 
-    private def buildAnnotationParameter(a: Annotation.AnnotationParameter): SignatureBuilder = a match {
-      case Annotation.PrimitiveParameter(name, value) =>
-        addParameterName(name).text(value)
-      case Annotation.LinkParameter(name, dri, text) =>
-        addParameterName(name).driLink(text, dri)
-      case Annotation.UnresolvedParameter(name, value) =>
-        addParameterName(name).text(value)
-    }
+  private def addParameterName(txt: Option[String]): SignatureBuilder = txt match {
+    case Some(name) => this.text(s"$name = ")
+    case _ => this
+  }
 
-    def modifiersAndVisibility(t: Member, kind: String) =
-      val (prefixMods, suffixMods) = t.modifiers.partition(_.prefix)
-      val all = prefixMods.map(_.name) ++ Seq(t.visibility.asSignature) ++ suffixMods.map(_.name)
+  private def buildAnnotationParameter(a: Annotation.AnnotationParameter): SignatureBuilder = a match {
+    case Annotation.PrimitiveParameter(name, value) =>
+      addParameterName(name).text(value)
+    case Annotation.LinkParameter(name, dri, text) =>
+      addParameterName(name).driLink(text, dri)
+    case Annotation.UnresolvedParameter(name, value) =>
+      addParameterName(name).text(value)
+  }
 
-      text(all.toSignatureString()).text(kind + " ")
+  def modifiersAndVisibility(t: Member, kind: String) =
+    val (prefixMods, suffixMods) = t.modifiers.partition(_.prefix)
+    val all = prefixMods.map(_.name) ++ Seq(t.visibility.asSignature) ++ suffixMods.map(_.name)
 
-    def generics(on: Seq[TypeParameter]) = list(on.toList, "[", "]"){ (bdr, e) =>
-      bdr.annotationsInline(e).text(e.variance).memberName(e.name, e.dri).signature(e.signature)
-    }
+    text(all.toSignatureString()).text(kind + " ")
 
-    def functionParameters(params: Seq[ParametersList]) =
-      if params.isEmpty then this.text("")
-      else if params.size == 1 && params(0).parameters == Nil then this.text("()")
-      else this.list(params, separator = ""){ (bld, pList) =>
-        bld.list(pList.parameters, s"(${pList.modifiers}", ")"){ (bld, p) =>
-            val annotationsAndModifiers = bld.annotationsInline(p)
-              .text(p.modifiers)
-            val name = p.name.fold(annotationsAndModifiers)(annotationsAndModifiers.memberName(_, p.dri).text(": "))
-            name.signature(p.signature)
-        }
+  def generics(on: Seq[TypeParameter]) = list(on.toList, "[", "]"){ (bdr, e) =>
+    bdr.annotationsInline(e).text(e.variance).memberName(e.name, e.dri).signature(e.signature)
+  }
+
+  def functionParameters(params: Seq[ParametersList]) =
+    if params.isEmpty then this.text("")
+    else if params.size == 1 && params(0).parameters == Nil then this.text("()")
+    else this.list(params, separator = ""){ (bld, pList) =>
+      bld.list(pList.parameters, s"(${pList.modifiers}", ")"){ (bld, p) =>
+        val annotationsAndModifiers = bld.annotationsInline(p)
+          .text(p.modifiers)
+        val name = p.name.fold(annotationsAndModifiers)(annotationsAndModifiers.memberName(_, p.dri).text(": "))
+        name.signature(p.signature)
       }
+    }
 }
 
 trait ScalaSignatureUtils: