fix name of Ident and Select trees for module class from java

compiler/src/dotty/tools/dotc/core/ContextOps.scala

@@ -64,10 +64,7 @@ object ContextOps:
         val directSearch =
           def asModule =
             if name.isTypeName && name.endsWith(StdNames.str.MODULE_SUFFIX) then
-              pre.findMember(name.stripModuleClassSuffix.moduleClassName, pre, required, excluded) match
-                case NoDenotation => NoDenotation
-                case symDenot: SymDenotation =>
-                  symDenot.companionModule.denot
+              pre.findMember(name.stripModuleClassSuffix.moduleClassName, pre, required, excluded)
             else NoDenotation
           pre.findMember(name, pre, required, excluded) match
             case NoDenotation => asModule

compiler/src/dotty/tools/dotc/typer/Typer.scala

@@ -631,7 +631,13 @@ class Typer(@constructorOnly nestingLevel: Int = 0) extends Namer
         case checkedType: NamedType if !prefixIsElidable(checkedType) =>
           ref(checkedType).withSpan(tree.span)
         case _ =>
-          tree.withType(checkedType)
+          def isScalaModuleRef = checkedType match
+            case moduleRef: TypeRef if moduleRef.symbol.is(ModuleClass, butNot = JavaDefined) => true
+            case _ => false
+          if ctx.isJava && isScalaModuleRef then
+            cpy.Ident(tree)(tree.name.unmangleClassName).withType(checkedType)
+          else
+            tree.withType(checkedType)
       val tree2 = toNotNullTermRef(tree1, pt)
       checkLegalValue(tree2, pt)
       tree2
@@ -688,11 +694,7 @@ class Typer(@constructorOnly nestingLevel: Int = 0) extends Namer
       report.error(StableIdentPattern(tree, pt), tree.srcPos)
 
   def typedSelect(tree0: untpd.Select, pt: Type, qual: Tree)(using Context): Tree =
-    val selName =
-      if ctx.isJava && tree0.name.isTypeName && tree0.name.endsWith(StdNames.str.MODULE_SUFFIX) then
-        tree0.name.stripModuleClassSuffix.moduleClassName
-      else
-        tree0.name
+    val selName = tree0.name
     val tree = cpy.Select(tree0)(qual, selName)
     val superAccess = qual.isInstanceOf[Super]
     val rawType = selectionType(tree, qual)
@@ -769,26 +771,30 @@ class Typer(@constructorOnly nestingLevel: Int = 0) extends Namer
 
     def typeSelectOnTerm(using Context): Tree =
       val qual = typedExpr(tree.qualifier, shallowSelectionProto(tree.name, pt, this, tree.nameSpan))
-      typedSelect(tree, pt, qual).withSpan(tree.span).computeNullable()
-
-    def javaSelectOnType(qual: Tree)(using Context) =
-      // semantic name conversion for `O$` in java code
-      if !qual.symbol.is(JavaDefined) then
-        val tree2 = untpd.cpy.Select(tree)(qual, tree.name.unmangleClassName)
-        assignType(tree2, qual)
+      if ctx.isJava then
+        javaSelection(qual)
       else
-        assignType(cpy.Select(tree)(qual, tree.name), qual)
+        typedSelect(tree, pt, qual).withSpan(tree.span).computeNullable()
+
+    def javaSelection(qual: Tree)(using Context) =
+      val tree1 = assignType(cpy.Select(tree)(qual, tree.name), qual)
+      tree1.tpe match
+        case moduleRef: TypeRef if moduleRef.symbol.is(ModuleClass, butNot = JavaDefined) =>
+          // handle unmangling of module names (Foo$ -> Foo[ModuleClass])
+          cpy.Select(tree)(qual, tree.name.unmangleClassName).withType(moduleRef)
+        case _ =>
+          tree1
 
     def tryJavaSelectOnType(using Context): Tree = tree.qualifier match {
       case sel @ Select(qual, name) =>
         val qual1 = untpd.cpy.Select(sel)(qual, name.toTypeName)
         val qual2 = typedType(qual1, WildcardType)
-        javaSelectOnType(qual2)
+        javaSelection(qual2)
 
       case id @ Ident(name) =>
         val qual1 = untpd.cpy.Ident(id)(name.toTypeName)
         val qual2 = typedType(qual1, WildcardType)
-        javaSelectOnType(qual2)
+        javaSelection(qual2)
 
       case _ =>
         errorTree(tree, em"cannot convert to type selection") // will never be printed due to fallback

tests/run/i17255/J.java

@@ -1,16 +1,29 @@
 package p;
 
 public class J {
-	public static J j = new J();
-	public static p.J f() {
-		return p.J.j;
-	}
-	public static Module$ module2() {
-		return p.Module$.MODULE$;
-	}
-	public static p.Module$ module() {
-		return p.Module$.MODULE$;
-	}
+  public static J j = new J();
 
-	public String toString() { return "J"; }
-}
+  public static p.J f() {
+    return p.J.j;
+  }
+
+  public static Module$ module2() {
+    return p.Module$.MODULE$;
+  }
+
+  public static p.Module$ module() {
+    return p.Module$.MODULE$;
+  }
+
+  public static Module.InnerModule$ innermodule2() {
+    return p.Module.InnerModule$.MODULE$;
+  }
+
+  public static p.Module.InnerModule$ innermodule() {
+    return p.Module.InnerModule$.MODULE$;
+  }
+
+  public String toString() {
+    return "J";
+  }
+}

tests/run/i17255/Module.scala

@@ -1,13 +1,17 @@
-// scalajs: --skip
-
 package p {
   object Module {
     override def toString = "Module"
+
+    object InnerModule {
+      override def toString = "InnerModule"
+    }
   }
 }
 
 object Test extends App {
   assert(p.J.f().toString == "J")
   assert(p.J.module().toString == "Module")
   assert(p.J.module2().toString == "Module")
-}
+  assert(p.J.innermodule().toString == "InnerModule")
+  assert(p.J.innermodule2().toString == "InnerModule")
+}