Merge pull request #10323 from som-snytt/issue/10589-case-implicit-param

Reification knows only first param list is case accessor
scala · Mar 13, 2023 · ca4831f · ca4831f
2 parents 122de8d + ad96fc4
commit ca4831f
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Showing 3 changed files with 32 additions and 3 deletions.
diff --git a/src/reflect/scala/reflect/internal/ReificationSupport.scala b/src/reflect/scala/reflect/internal/ReificationSupport.scala
@@ -124,7 +124,7 @@ trait ReificationSupport { self: SymbolTable =>
     def mkAnnotation(trees: List[Tree]): List[Tree] = trees.map(mkAnnotation)
 
     def mkParam(argss: List[List[Tree]], extraFlags: FlagSet = NoFlags, excludeFlags: FlagSet = DEFERRED): List[List[ValDef]] =
-      argss.map { args => args.map { mkParam(_, extraFlags, excludeFlags) } }
+      argss.map(_.map(mkParam(_, extraFlags, excludeFlags)))
 
     def mkParam(tree: Tree, extraFlags: FlagSet, excludeFlags: FlagSet): ValDef = tree match {
       case Typed(Ident(name: TermName), tpt) =>
@@ -344,8 +344,12 @@ trait ReificationSupport { self: SymbolTable =>
       def apply(mods: Modifiers, name: TypeName, tparams: List[Tree],
                 constrMods: Modifiers, vparamss: List[List[Tree]],
                 earlyDefs: List[Tree], parents: List[Tree], selfType: Tree, body: List[Tree]): ClassDef = {
-        val extraFlags = PARAMACCESSOR | (if (mods.isCase) CASEACCESSOR else 0L)
-        val vparamss0 = mkParam(vparamss, extraFlags, excludeFlags = DEFERRED | PARAM)
+        val extraCaseFlags = if (mods.isCase) CASEACCESSOR else 0L
+        val excludeFlags = DEFERRED | PARAM
+        val vparamss0 =
+          if (vparamss.isEmpty) vparamss.asInstanceOf[List[List[ValDef]]]
+          else mkParam(vparamss.head :: Nil, PARAMACCESSOR | extraCaseFlags, excludeFlags) ++
+               mkParam(vparamss.tail, PARAMACCESSOR, excludeFlags)
         val tparams0 = mkTparams(tparams)
         val parents0 = gen.mkParents(mods,
           if (mods.isCase) parents.filter {

diff --git a/test/files/pos/t10589-case-implicit-param/cc_2.scala b/test/files/pos/t10589-case-implicit-param/cc_2.scala
@@ -0,0 +1,6 @@
+// scalac: -Ymacro-annotations
+trait T[A]
+
+@macid
+case class CC[A: T](x: A)
+
diff --git a/test/files/pos/t10589-case-implicit-param/macros_1.scala b/test/files/pos/t10589-case-implicit-param/macros_1.scala
@@ -0,0 +1,19 @@
+// scalac: -Ymacro-annotations
+
+import scala.annotation.StaticAnnotation
+import scala.language.experimental.macros
+import scala.reflect.macros.whitebox.Context
+
+class macid extends StaticAnnotation {
+  def macroTransform(annottees: Any*): Any = macro macidMacro.impl
+}
+object macidMacro {
+  def impl(c: Context)(annottees: c.Expr[Any]*): c.Expr[Any] = {
+    new Macros[c.type](c).macidMacroImpl(annottees.toList)
+  }
+}
+class Macros[C <: Context](val c: C) {
+  import c.universe._
+  def macidMacroImpl(annottees: List[c.Expr[Any]]): c.Expr[Any] =
+    annottees(0)
+}