Made db.full_coll_name public. Wrote a test for it.

lib/mongo/db.rb

@@ -160,12 +160,12 @@ module XGen
           @socket.print(message.buf.to_s)
         end
 
-        protected
-
         def full_coll_name(collection)
           "#{@name}.#{collection}"
         end
 
+        protected
+
         def db_command(selector)
           # TODO synchronize
           q = Query.new(selector)

tests/test_db_api.rb

@@ -76,4 +76,8 @@ class DBAPITest < Test::Unit::TestCase
     # Mongo bug: returns string with wrong length, so last byte of value is chopped off.
 #     assert_equal @coll.name, row['options']['create']
   end
+
+  def test_full_coll_name
+    assert_equal @coll_full_name, @db.full_coll_name(@coll.name)
+  end
 end