Created invisible setting to expose empty packa...

Created invisible setting to expose empty package members outside of the
empty package, so the repl can use packages without going blind to the
empty package. This commit also eliminates a deadlock which hits when
the compiler starts logging before a lazy val has pulled its head from
the noose. Closes #4228, review by odersky.

1 files changed, 16 insertions, 3 deletions

diff --git a/src/compiler/scala/tools/nsc/typechecker/Typers.scala b/src/compiler/scala/tools/nsc/typechecker/Typers.scala
index 396bb5ca0e..d805a33940 100644
--- a/src/compiler/scala/tools/nsc/typechecker/Typers.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/Typers.scala
@@ -3575,6 +3575,14 @@ trait Typers extends Modes {
                                           // for being inaccessible; used for error reporting
         var inaccessibleExplanation: String = ""
 
+        // If a special setting is given, the empty package will be checked as a
+        // last ditch effort before failing.  This method sets defSym and returns
+        // true if a member of the given name exists.
+        def checkEmptyPackage(): Boolean = {
+          defSym = EmptyPackageClass.tpe.nonPrivateMember(name)
+          defSym != NoSymbol
+        }
+
         // A symbol qualifies if it exists and is not stale. Stale symbols
         // are made to disappear here. In addition,
         // if we are in a constructor of a pattern, we ignore all definitions
@@ -3679,15 +3687,20 @@ trait Typers extends Modes {
               if (!(shortenImports && qual0.symbol.isPackage)) // optimization: don't write out package prefixes
                 qual = atPos(tree.pos.focusStart)(resetPos(qual0.duplicate))
               pre = qual.tpe
-            } else {
+            }
+            else if (settings.exposeEmptyPackage.value && checkEmptyPackage())
+              log("Allowing empty package member " + name + " due to settings.")
+            else {
               if (settings.debug.value) {
                 log(context.imports)//debug
               }
               if (inaccessibleSym eq NoSymbol) {
                 error(tree.pos, "not found: "+decodeWithNamespace(name))
-              } else accessError(
+              }
+              else accessError(
                 tree, inaccessibleSym, context.enclClass.owner.thisType,
-                inaccessibleExplanation)
+                inaccessibleExplanation
+              )
               defSym = context.owner.newErrorSymbol(name)
             }
           }