Bullet-proofing companion objects

Companion class/module computations now also work for local classes and modules. For this to work,
either one of two conditions must be met: (1) some enclosing context refers to a scope that
contains the companions. (2) the context's compilation unit has a typed tree that contains the
companions. (1) is usually true when type-checking, (2) when transforming trees.

Local companions are searched as follows: If (2) holds, we locate the statement sequence containing
the companions by searching down from the root stored in the compilation unit. Otherwise, we search
outwards in the enclosing contexts for a scope containing the
companions.

1 files changed, 28 insertions, 0 deletions

diff --git a/tests/pos/companions.scala b/tests/pos/companions.scala
new file mode 100644
index 000000000..6821ad768
--- /dev/null
+++ b/tests/pos/companions.scala
@@ -0,0 +1,28 @@
+object companions {
+
+  def foo() = {
+
+    class C {
+      println(C.p)
+      private val q = 2
+    }
+
+    object C {
+      private val p = 1
+      println(new C().q)
+    }
+  }
+
+}
+object companions2 {
+  def foo() = {
+     {
+      class C {
+        println(C.p)
+      }
+      object C {
+        private val p = 1
+      }
+    }
+  }
+}