fix: insert missing members in correct place for case classes

Author: kasiaMarek

presentation-compiler/src/main/dotty/tools/pc/completions/OverrideCompletions.scala

@@ -506,6 +506,8 @@ object OverrideCompletions:
     defn match
       case td: TypeDef if text.charAt(td.rhs.span.end) == ':' =>
         Some(td.rhs.span.end)
+      case TypeDef(_, temp : Template) =>
+        temp.parentsOrDerived.lastOption.map(_.span.end).filter(text.charAt(_) == ':')
       case _ => None
 
   private def fallbackFromParent(parent: Tree, name: String)(using Context) =

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

@@ -1272,6 +1272,35 @@ class AutoImplementAbstractMembersSuite extends BaseCodeActionSuite:
          |""".stripMargin,
     )
 
+  @Test def `braceless-case-class` =
+    checkEdit(
+      """|package a
+         |
+         |trait Base:
+         |  def foo(x: Int): Int
+         |  def bar(x: String): String
+         |
+         |case class <<Concrete>>() extends Base:
+         |  def aaa = "aaa"
+         |end Concrete
+         |""".stripMargin,
+      """|package a
+         |
+         |trait Base:
+         |  def foo(x: Int): Int
+         |  def bar(x: String): String
+         |
+         |case class Concrete() extends Base:
+         |
+         |  override def bar(x: String): String = ???
+         |
+         |  override def foo(x: Int): Int = ???
+         |
+         |  def aaa = "aaa"
+         |end Concrete
+         |""".stripMargin
+    )
+
   def checkEdit(
       original: String,
       expected: String