created Redistat::Synchronize mixin to help with thread-safety

spec/synchronize_spec.rb

@@ -0,0 +1,64 @@
+require "spec_helper"
+
+describe Redistat::Synchronize do
+  it { should respond_to(:monitor) }
+  it { should respond_to(:thread_safe) }
+  it { should respond_to(:thread_safe=) }
+  
+  describe "instanciated class with Redistat::Synchronize included" do
+    subject { SynchronizeSpecHelper.new }
+    it { should respond_to(:monitor) }
+    it { should respond_to(:thread_safe) }
+    it { should respond_to(:thread_safe=) }
+    it { should respond_to(:synchronize) }
+    
+  end
+  
+  describe "#synchronize method" do
+    
+    before(:each) do
+      Redistat::Synchronize.instance_variable_set("@thread_safe", nil)
+      @obj = SynchronizeSpecHelper.new
+    end
+    
+    it "should share single Monitor object across all objects" do
+      @obj.monitor.should == Redistat::Synchronize.monitor
+    end
+    
+    it "should share thread_safe option across all objects" do
+      obj2 = SynchronizeSpecHelper.new
+      Redistat::Synchronize.thread_safe.should be_false
+      @obj.thread_safe.should be_false
+      obj2.thread_safe.should be_false
+      @obj.thread_safe = true
+      Redistat::Synchronize.thread_safe.should be_true
+      @obj.thread_safe.should be_true
+      obj2.thread_safe.should be_true
+    end
+    
+    it "should not synchronize when thread_safe is disabled" do
+      # monitor receives :synchronize twice cause #thread_safe is _always_ synchronized
+      Redistat::Synchronize.monitor.should_receive(:synchronize).twice
+      @obj.thread_safe.should be_false # first #synchronize call
+      @obj.synchronize { 'foo' } # one #synchronize call while checking #thread_safe
+    end
+    
+    it "should synchronize when thread_safe is enabled" do
+      Monitor.class_eval {
+        # we're stubbing synchronize to ensure it's being called correctly, but still need it :P
+        alias :real_synchronize :synchronize
+      }
+      Redistat::Synchronize.monitor.should_receive(:synchronize).with.exactly(4).times.and_return { |block|
+        Redistat::Synchronize.monitor.real_synchronize(&block)
+      }
+      @obj.thread_safe.should be_false # first synchronize call
+      Redistat::Synchronize.thread_safe = true # second synchronize call
+      @obj.synchronize { 'foo' } # two synchronize calls, once while checking thread_safe, once to call black
+    end
+  end
+  
+end
+
+class SynchronizeSpecHelper
+  include Redistat::Synchronize
+end