Add cache to avoid multiple definitions

Author: hamzaremmal

compiler/src/dotty/tools/dotc/transform/MacroAnnotations.scala

@@ -61,12 +61,9 @@ class MacroAnnotations(phase: IdentityDenotTransformer):
               insertedAfter = suffixed :: insertedAfter
               for prefixedTree <- prefixed do
                 checkMacroDef(prefixedTree, tree, annot)
-                enterMissingSymbols(prefixedTree)
               for suffixedTree <- suffixed do
                 checkMacroDef(suffixedTree, tree, annot)
-                enterMissingSymbols(suffixedTree)
               TreeChecker.checkMacroGeneratedTree(tree, newTree)
-              enterMissingSymbols(newTree)
               newTree
             case (Nil, Nil) =>
               report.error(i"Unexpected `Nil` returned by `(${annot.tree}).transform(..)` during macro expansion", annot.tree.srcPos)
@@ -82,6 +79,7 @@ class MacroAnnotations(phase: IdentityDenotTransformer):
       insertedAfter.foreach(allTrees.++=)
 
       val result = allTrees.result()
+      for tree <- result do enterMissingSymbols(tree)
       debug.println(result.map(_.show).mkString("expanded to:\n", "\n", ""))
       result
 
@@ -136,7 +134,7 @@ class MacroAnnotations(phase: IdentityDenotTransformer):
     else if annotated.isClass && annotated.owner.is(Package) /*&& !sym.isClass*/ then
       report.error(i"macro annotation can not add top-level ${sym.showKind}. $annot tried to add $sym.", annot.tree)
 
-  private def enterMissingSymbols(tree: MemberDef)(using Context) = new TreeTraverser {
+  private def enterMissingSymbols(tree: DefTree)(using Context) = new TreeTraverser {
     def traverse(tree: tpd.Tree)(using Context): Unit = tree match
       case tdef @ TypeDef(_, template: Template) =>
         //for tree <- template.constr :: template.body do
@@ -146,7 +144,7 @@ class MacroAnnotations(phase: IdentityDenotTransformer):
             report.error(em"Macro added a definition with the wrong owner - ${tree.symbol.owner} - ${tdef.symbol} in ${tree.source}")
           else if !isSymbolInDecls(tree.symbol) then
             tree.symbol.enteredAfter(phase)
-        traverseChildren(tree) // Taverse before or after dealing with this class?
+        traverseChildren(tree) // Traverse before or after dealing with this class?
       case _ => traverseChildren(tree)
   }.traverse(tree)