Fix printing super prefix

Author: nicolasstucki

library/src/scala/tasty/util/ShowSourceCode.scala

@@ -317,6 +317,10 @@ class ShowSourceCode[T <: Tasty with Singleton](tasty0: T) extends Show[T](tasty
         }
 
       case Term.Super(qual, idOpt) =>
+        qual match {
+          case Term.This(Some(Id(name))) => this += name += "."
+          case Term.This(None) =>
+        }
         this += "super"
         for (id <- idOpt) {
           val Id(name) = id

tests/run/t4300.decompiled

@@ -0,0 +1,28 @@
+/** Decompiled from out/runTestFromTasty/run/t4300/A.class */
+trait A() extends java.lang.Object {
+  def f(): scala.Unit = scala.Predef.println("A")
+}
+/** Decompiled from out/runTestFromTasty/run/t4300/B.class */
+class B() extends A {
+  def b(): scala.Unit = super[A].f()
+  trait C() extends java.lang.Object {
+    def c(): scala.Unit = B.super[A].f()
+  }
+  def g(): scala.Unit = scala.Predef.intWrapper(0).until(1).foreach[scala.Unit](((i: scala.Int) => super[A].f()))
+  def h(): scala.Unit = scala.Predef.intWrapper(0).until(1).foreach[scala.Unit](((i: scala.Int) => B.super[A].f()))
+  override def f(): scala.Unit = scala.Predef.println("B")
+}
+/** Decompiled from out/runTestFromTasty/run/t4300/Test.class */
+object Test {
+  def main(args: scala.Array[scala.Predef.String]): scala.Unit = {
+    val b: B = new B()
+    b.b()
+
+    {
+      final class $anon() extends b.C()
+      (new $anon(): b.C)
+    }.c()
+    b.g()
+    b.h()
+  }
+}