RUBY-236 more timeout tweaks and tests

lib/mongo.rb

@@ -80,11 +80,14 @@ require 'mongo/gridfs/grid_file_system'
 if !defined?(RUBY_ENGINE) || (RUBY_ENGINE == 'ruby' && RUBY_VERSION < '1.9.0')
   begin
     require 'system_timer'
+    if SystemTimer.method(:timeout).arity.abs != 2
+      raise LoadError
+    end
     Mongo::TimeoutHandler = SystemTimer
   rescue LoadError
-    warn "Could not load SystemTimer gem. Falling back to timeout.rb. " +
+    warn "Could not load SystemTimer >= v1.2.0. Falling back to timeout.rb. " +
          "SystemTimer is STRONGLY recommended for timeouts in Ruby 1.8.7. " +
-         "See http://ph7spot.com/musings/system-timer for details."
+         "See http://ph7spot.com/blog/system-timer-1-2-release for details."
     require 'timeout'
     Mongo::TimeoutHandler = Timeout
   end

lib/mongo/connection.rb

@@ -838,6 +838,7 @@ module Mongo
     def receive_message_on_socket(length, socket)
       begin
         if @op_timeout
+          message = nil
           Mongo::TimeoutHandler.timeout(@op_timeout, OperationTimeout) do
             message = receive_data(length, socket)
           end
@@ -848,7 +849,7 @@ module Mongo
           close
 
           if ex.class == OperationTimeout
-            raise OperationTimeout, "Timed out waiting in socket read."
+            raise OperationTimeout, "Timed out waiting on socket read."
           else
             raise ConnectionFailure, "Operation failed with the following exception: #{ex}"
           end

test/collection_test.rb

@@ -1,7 +1,7 @@
 require './test/test_helper'
 
 class TestCollection < Test::Unit::TestCase
-  @@connection ||= standard_connection
+  @@connection ||= standard_connection(:op_timeout => 2)
   @@db   = @@connection.db(MONGO_TEST_DB)
   @@test = @@db.collection("test")
   @@version = @@connection.server_version