1 files changed, 15 insertions, 4 deletions
diff --git a/spec/ruby/library/monitor/synchronize_spec.rb b/spec/ruby/library/monitor/synchronize_spec.rb
index d851b98d6c..d78393eb3a 100644
--- a/spec/ruby/library/monitor/synchronize_spec.rb
+++ b/spec/ruby/library/monitor/synchronize_spec.rb
@@ -7,24 +7,35 @@ describe "Monitor#synchronize" do
 
     monitor = Monitor.new
     10.times do
-      locked = false
+      wait_q = Queue.new
+      continue_q = Queue.new
 
       thread = Thread.new do
         begin
           monitor.synchronize do
-            locked = true
+            wait_q << true
             # Do not wait here, we are trying to interrupt the ensure part of #synchronize
           end
-          sleep # wait for exception if it did not happen yet
+          continue_q.pop
         rescue exc_class
           monitor.should_not.mon_locked?
           :ok
         end
       end
 
-      Thread.pass until locked
+      wait_q.pop
       thread.raise exc_class, "interrupt"
+      continue_q << true
       thread.value.should == :ok
     end
   end
+
+  it "raises a LocalJumpError if not passed a block" do
+    -> { Monitor.new.synchronize }.should raise_error(LocalJumpError)
+  end
+
+  it "raises a thread error if the monitor is not owned on exiting the block" do
+    monitor = Monitor.new
+    -> { monitor.synchronize { monitor.exit } }.should raise_error(ThreadError)
+  end
 end