Merge pull request #64 from fauna/rescue_ConnectionDataExists

Don't raise ConnectionDataExists from cas() in the Rails adaptor.

CHANGELOG

@@ -1,3 +1,5 @@
+v1.3.1 rescue ConnectionDataExists for cas because Rails shim over Memcached is not supposed to raise anything for legacy reasons
+
 v1.3. Improvements to BSD support; add Memcached#touch method (avsej).
 
 v1.2.7.1 Retry SomeErrorsWereReported exception

lib/memcached/rails.rb

@@ -60,7 +60,7 @@ def exist?(key, options = {})
     def cas(key, ttl=@default_ttl, raw=false, &block)
       super(key, ttl, !raw, &block)
       true
-    rescue NotFound
+    rescue NotFound, ConnectionDataExists
       false
     end
 

test/unit/rails_test.rb

@@ -87,14 +87,16 @@ def test_cas
     assert_nil cache.get(key)
     assert_nil @called
 
-    # Conflicting set
+    # Conflicting set after a gets
     cache.set key, @value
-    assert_raises(Memcached::ConnectionDataExists) do
-      cache.cas(key) do |current|
+    assert_nothing_raised do
+      result = cache.cas(key) do |current|
         cache.set key, value2
         current
       end
+      assert_equal result, false
     end
+    assert_equal value2, cache.get(key)
   end
 
   def test_get_missing