From 3a06cc96336409a43b50706a5980498287d74f29 Mon Sep 17 00:00:00 2001
From: Jay Pignata <john.pignata@gmail.com>
Date: Sat, 26 Sep 2009 22:08:55 -0400
Subject: [PATCH] Adding NullStore to ActiveSupport::Cache

---
 activesupport/lib/active_support/cache.rb          |    1 +
 .../lib/active_support/cache/null_store.rb         |   43 ++++++++++++++++++++
 activesupport/test/caching_test.rb                 |   37 +++++++++++++++++
 3 files changed, 81 insertions(+), 0 deletions(-)
 create mode 100644 activesupport/lib/active_support/cache/null_store.rb

diff --git a/activesupport/lib/active_support/cache.rb b/activesupport/lib/active_support/cache.rb
index 25f9555..82eab76 100644
--- a/activesupport/lib/active_support/cache.rb
+++ b/activesupport/lib/active_support/cache.rb
@@ -17,6 +17,7 @@ module ActiveSupport
     autoload :SynchronizedMemoryStore, 'active_support/cache/synchronized_memory_store'
     autoload :MemCacheStore, 'active_support/cache/mem_cache_store'
     autoload :CompressedMemCacheStore, 'active_support/cache/compressed_mem_cache_store'
+    autoload :NullStore, 'active_support/cache/null_store'
 
     module Strategy
       autoload :LocalCache, 'active_support/cache/strategy/local_cache'
diff --git a/activesupport/lib/active_support/cache/null_store.rb b/activesupport/lib/active_support/cache/null_store.rb
new file mode 100644
index 0000000..c068cd6
--- /dev/null
+++ b/activesupport/lib/active_support/cache/null_store.rb
@@ -0,0 +1,43 @@
+module ActiveSupport
+  module Cache
+    # A dummy cache store implementation for testing and debugging purposes. When configured, calls to 
+    # Rails.cache will be logged but reading and writing from the cache will be disabled. 
+    class NullStore < Store
+      def read(name, options = nil)
+        super do
+          nil
+        end
+      end
+
+      def write(name, value, options = nil)
+        super do
+          value
+        end
+      end
+
+      def delete(name, options = nil)
+        super do
+          nil
+        end
+      end
+
+      def exist?(name, options = nil)
+        super do
+          false
+        end
+      end
+
+      def increment(name, options = nil)
+        super do
+          nil
+        end
+      end
+
+      def decrement(name, options = nil)
+        super do
+          nil
+        end
+      end
+    end
+  end
+end
\ No newline at end of file
diff --git a/activesupport/test/caching_test.rb b/activesupport/test/caching_test.rb
index 7667f11..57a0f2b 100644
--- a/activesupport/test/caching_test.rb
+++ b/activesupport/test/caching_test.rb
@@ -342,3 +342,40 @@ uses_memcached 'memcached backed store' do
     include CacheStoreBehavior
   end
 end
+
+class NullStoreTest < ActiveSupport::TestCase
+  def setup
+    @cache = ActiveSupport::Cache.lookup_store(:null_store)
+  end
+  
+  def test_write
+    @cache.write('foo', 'bar')
+    @cache.write('baz', {:a => 'b'})
+    @cache.write('foz', 2)
+
+    assert_nil @cache.fetch('foo')
+    assert_nil @cache.fetch('baz')
+    assert_nil @cache.fetch('foz')
+  end
+
+  def test_fetch
+    assert_equal 'baz', @cache.fetch('foo') { 'baz' }
+    assert_equal 'bar', @cache.fetch('foo') { 'bar' }
+  end
+
+  def test_increment
+    @cache.write('foo', 1, :raw => true)
+    assert_nil @cache.increment('foo')
+  end
+
+  def test_decrement
+    @cache.write('foo', 3, :raw => true)
+    assert_nil @cache.decrement('foo')
+  end
+
+  def test_exist
+    @cache.write('foo', 'bar')
+    assert !@cache.exist?('foo')
+  end  
+end
+
-- 
1.6.4.2