Merge pull request scala#3602 from xeno-by/topic/backport-vampire-warning

retronym · retronym · commit daa77d15dd11 · 2014-03-22T15:31:38.000+01:00
[backport] no longer warns on calls to vampire macros
diff --git a/src/compiler/scala/tools/nsc/typechecker/Typers.scala b/src/compiler/scala/tools/nsc/typechecker/Typers.scala
@@ -4934,7 +4934,7 @@ trait Typers extends Modes with Adaptations with Tags {
 
             if (tree.isInstanceOf[PostfixSelect])
               checkFeature(tree.pos, PostfixOpsFeature, name.decode)
-            if (tree1.symbol != null && tree1.symbol.isOnlyRefinementMember)
+            if (tree1.symbol != null && tree1.symbol.isOnlyRefinementMember && !tree1.symbol.isMacro)
               checkFeature(tree1.pos, ReflectiveCallsFeature, tree1.symbol.toString)
 
             if (qual1.hasSymbolWhich(_.isRootPackage)) treeCopy.Ident(tree1, name)
diff --git a/test/files/run/macro-vampire-false-warning.check b/test/files/run/macro-vampire-false-warning.check
@@ -0,0 +1,2 @@
+2
+3
diff --git a/test/files/run/macro-vampire-false-warning.flags b/test/files/run/macro-vampire-false-warning.flags
@@ -0,0 +1 @@
+-Xfatal-warnings
diff --git a/test/files/run/macro-vampire-false-warning/Macros_1.scala b/test/files/run/macro-vampire-false-warning/Macros_1.scala
@@ -0,0 +1,52 @@
+// As per http://meta.plasm.us/posts/2013/08/31/feeding-our-vampires/
+
+import scala.annotation.StaticAnnotation
+import scala.reflect.macros.Context
+import scala.language.experimental.macros
+
+class body(tree: Any) extends StaticAnnotation
+
+object Macros {
+  def selFieldImpl(c: Context) = {
+    import c.universe._
+    val field = c.macroApplication.symbol
+    val bodyAnn = field.annotations.filter(_.tpe <:< typeOf[body]).head
+    c.Expr[Any](bodyAnn.scalaArgs.head)
+  }
+
+  def mkObjectImpl(c: Context)(xs: c.Expr[Any]*) = {
+    import c.universe._
+    import Flag._
+    // val kvps = xs.toList map { case q"${_}(${Literal(Constant(name: String))}).->[${_}]($value)" => name -> value }
+    val kvps = xs.map(_.tree).toList map { case Apply(TypeApply(Select(Apply(_, List(Literal(Constant(name: String)))), _), _), List(value)) => name -> value }
+    // val fields = kvps map { case (k, v) => q"@body($v) def ${TermName(k)} = macro Macros.selFieldImpl" }
+    val fields = kvps map { case (k, v) => DefDef(
+      Modifiers(MACRO, tpnme.EMPTY, List(Apply(Select(New(Ident(newTypeName("body"))), nme.CONSTRUCTOR), List(v)))),
+      newTermName(k), Nil, Nil, TypeTree(), Select(Ident(newTermName("Macros")), newTermName("selFieldImpl"))) }
+    // q"import scala.language.experimental.macros; class Workaround { ..$fields }; new Workaround{}"
+    c.Expr[Any](Block(
+      List(
+        Import(Select(Select(Ident(newTermName("scala")), newTermName("language")), newTermName("experimental")), List(ImportSelector(newTermName("macros"), 51, newTermName("macros"), 51))),
+        ClassDef(
+          NoMods, newTypeName("Workaround"), Nil,
+          Template(
+            List(Select(Ident(newTermName("scala")), newTypeName("AnyRef"))), emptyValDef,
+            DefDef(
+              NoMods, nme.CONSTRUCTOR, Nil, List(Nil), TypeTree(),
+              Block(List(Apply(Select(Super(This(tpnme.EMPTY), tpnme.EMPTY), nme.CONSTRUCTOR), List())), Literal(Constant(()))))
+            +: fields)),
+        ClassDef(
+          Modifiers(FINAL), newTypeName("$anon"), Nil,
+          Template(
+            List(Ident(newTypeName("Workaround"))), emptyValDef,
+            List(
+              DefDef(
+                NoMods, nme.CONSTRUCTOR, Nil, List(Nil), TypeTree(),
+                Block(List(Apply(Select(Super(This(tpnme.EMPTY), tpnme.EMPTY), nme.CONSTRUCTOR), List())), Literal(Constant(())))))))),
+      Apply(Select(New(Ident(newTypeName("$anon"))), nme.CONSTRUCTOR), List())))
+  }
+}
+
+object mkObject {
+  def apply(xs: Any*) = macro Macros.mkObjectImpl
+}
diff --git a/test/files/run/macro-vampire-false-warning/Test_2.scala b/test/files/run/macro-vampire-false-warning/Test_2.scala
@@ -0,0 +1,6 @@
+object Test extends App {
+  val foo = mkObject("x" -> "2", "y" -> 3)
+  println(foo.x)
+  println(foo.y)
+  // println(foo.z) => will result in a compilation error
+}
