[nomaster] typecheck(q"class C") no longer crashes

MemberDefs alone can't be typechecked as is, because namer only names
contents of PackageDefs, Templates and Blocks. And, if not named, a tree
can't be typed.

This commit solves this problem by wrapping typecheckees in a trivial block
and then unwrapping the result when it returns back from the typechecker.

(cherry picked from commit 609047ba372ceaf06916d3361954bc949a6906ee)

3 files changed, 32 insertions, 0 deletions

diff --git a/test/files/run/typecheck.check b/test/files/run/typecheck.check
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/test/files/run/typecheck.check
diff --git a/test/files/run/typecheck/Macros_1.scala b/test/files/run/typecheck/Macros_1.scala
new file mode 100644
index 0000000000..850a611ab1
--- /dev/null
+++ b/test/files/run/typecheck/Macros_1.scala
@@ -0,0 +1,17 @@
+import scala.reflect.macros.Context
+import scala.language.experimental.macros
+
+object Macros {
+  def impl(c: Context) = {
+    import c.universe._
+    val classDef = ClassDef(
+      Modifiers(), newTypeName("C"), List(),
+      Template(
+        List(Select(Ident(newTermName("scala")), newTypeName("AnyRef"))), emptyValDef,
+        List(DefDef(Modifiers(), nme.CONSTRUCTOR, List(), List(List()), TypeTree(), Block(List(Apply(Select(Super(This(tpnme.EMPTY), tpnme.EMPTY), nme.CONSTRUCTOR), List())), Literal(Constant(())))))))
+    c.typeCheck(classDef)
+    c.Expr[Any](Literal(Constant(())))
+  }
+
+  def foo: Any = macro impl
+}
\ No newline at end of file
diff --git a/test/files/run/typecheck/Test_2.scala b/test/files/run/typecheck/Test_2.scala
new file mode 100644
index 0000000000..0a3279e23e
--- /dev/null
+++ b/test/files/run/typecheck/Test_2.scala
@@ -0,0 +1,15 @@
+import scala.reflect.runtime.universe._
+import scala.reflect.runtime.{currentMirror => cm}
+import scala.tools.reflect.ToolBox
+
+object Test extends App {
+  Macros.foo
+
+  val tb = cm.mkToolBox()
+  val classDef = ClassDef(
+    Modifiers(), newTypeName("C"), List(),
+    Template(
+      List(Select(Ident(newTermName("scala")), newTypeName("AnyRef"))), emptyValDef,
+      List(DefDef(Modifiers(), nme.CONSTRUCTOR, List(), List(List()), TypeTree(), Block(List(Apply(Select(Super(This(tpnme.EMPTY), tpnme.EMPTY), nme.CONSTRUCTOR), List())), Literal(Constant(())))))))
+  tb.typeCheck(classDef)
+}
\ No newline at end of file