Work around scala/scala3#19019: patch the SelfDef of inner module classes.

Re-create the correct self type which is a term reference to the
accompanying lazy val.

Author: sjrd

tasty-query/shared/src/main/scala/tastyquery/reader/tasties/TreeUnpickler.scala

@@ -685,7 +685,17 @@ private[tasties] class TreeUnpickler private (
           case _     => readTypeTree
         }
       }
-    val self = readSelf
+
+    val self0 = readSelf
+    val self = self0 match
+      case Some(orig @ SelfDef(name, tpt)) if cls.name.isObjectClassTypeName && cls.owner.isClass =>
+        // Work around https://github.com/lampepfl/dotty/issues/19019: replace with a correct SELFDEF
+        val owner = cls.owner.asClass
+        val fixedTpt = TypeWrapper(TermRef(owner.thisType, cls.name.sourceObjectName))(orig.pos)
+        Some(SelfDef(name, fixedTpt)(orig.pos))
+      case _ =>
+        self0
+
     cls.withGivenSelfType(self.map(_.tpt.toType))
     // The first entry is the constructor
     val cstr = readStat.asInstanceOf[DefDef]

test-sources/src/main/scala/simple_trees/ObjectWithSelf.scala

@@ -0,0 +1,43 @@
+package simple_trees
+
+object ObjectWithSelf:
+  object StaticObjectNoSelf:
+    def foo: Any = this
+    def bar: Any = this.foo
+  end StaticObjectNoSelf
+
+  object StaticObjectWithSelf:
+    self =>
+
+    def foo: Any = self
+    def bar: Any = self.foo
+  end StaticObjectWithSelf
+
+  class Container:
+    object NonStaticObjectNoSelf:
+      def foo: Any = this
+      def bar: Any = this.foo
+    end NonStaticObjectNoSelf
+
+    object NonStaticObjectWithSelf:
+      self =>
+
+      def foo: Any = self
+      def bar: Any = self.foo // used to cause StackOverflow while resolving this in WholeClasspathSuite tests
+    end NonStaticObjectWithSelf
+  end Container
+
+  def methodOwner(): Unit =
+    object LocalObjectNoSelf:
+      def foo: Any = this
+      def bar: Any = this.foo
+    end LocalObjectNoSelf
+
+    object LocalObjectWithSelf:
+      self =>
+
+      def foo: Any = self
+      def bar: Any = self.foo
+    end LocalObjectWithSelf
+  end methodOwner
+end ObjectWithSelf