From 1538ea1443b45faf0a70c3cae824e8b635f08821 Mon Sep 17 00:00:00 2001
From: Ryan Bates <ryan@railscasts.com>
Date: Mon, 11 Aug 2008 15:23:34 -0700
Subject: [PATCH] disable caching by default in development with NoStore which always returns nil on read

---
 activesupport/lib/active_support/cache.rb          |    1 +
 activesupport/lib/active_support/cache/no_store.rb |   10 ++++++++++
 activesupport/test/caching_test.rb                 |   16 ++++++++++++++++
 railties/lib/initializer.rb                        |    5 +++--
 4 files changed, 30 insertions(+), 2 deletions(-)
 create mode 100644 activesupport/lib/active_support/cache/no_store.rb

diff --git a/activesupport/lib/active_support/cache.rb b/activesupport/lib/active_support/cache.rb
index 95eae3a..0c395e4 100644
--- a/activesupport/lib/active_support/cache.rb
+++ b/activesupport/lib/active_support/cache.rb
@@ -119,3 +119,4 @@ require 'active_support/cache/memory_store'
 require 'active_support/cache/drb_store'
 require 'active_support/cache/mem_cache_store'
 require 'active_support/cache/compressed_mem_cache_store'
+require 'active_support/cache/no_store'
diff --git a/activesupport/lib/active_support/cache/no_store.rb b/activesupport/lib/active_support/cache/no_store.rb
new file mode 100644
index 0000000..46a44b9
--- /dev/null
+++ b/activesupport/lib/active_support/cache/no_store.rb
@@ -0,0 +1,10 @@
+module ActiveSupport
+  module Cache
+    class NoStore < Store
+      def read(name, options = nil)
+        super
+        nil
+      end
+    end
+  end
+end
diff --git a/activesupport/test/caching_test.rb b/activesupport/test/caching_test.rb
index f3220d2..1011302 100644
--- a/activesupport/test/caching_test.rb
+++ b/activesupport/test/caching_test.rb
@@ -70,3 +70,19 @@ uses_mocha 'high-level cache store tests' do
     end
   end
 end
+
+
+class NoStoreTest < Test::Unit::TestCase
+  def setup
+    @cache = ActiveSupport::Cache.lookup_store(:no_store)
+  end
+  
+  def test_read_should_always_return_nil
+    @cache.write('foo', 'bar')
+    assert_nil @cache.read('foo')
+  end
+  
+  def test_fetch_should_return_object_in_block
+    assert_equal 'bar', @cache.fetch('foo') { 'bar' }
+  end
+end
diff --git a/railties/lib/initializer.rb b/railties/lib/initializer.rb
index 6576cd3..50bc9c5 100644
--- a/railties/lib/initializer.rb
+++ b/railties/lib/initializer.rb
@@ -745,6 +745,7 @@ Run `rake gems:install` to install the missing gems.
       self.database_configuration_file  = default_database_configuration_file
       self.routes_configuration_file    = default_routes_configuration_file
       self.gems                         = default_gems
+      self.cache_store                  = default_cache_store
 
       for framework in default_frameworks
         self.send("#{framework}=", Rails::OrderedOptions.new)
@@ -949,8 +950,8 @@ Run `rake gems:install` to install the missing gems.
       end
 
       def default_cache_store
-        if File.exist?("#{root_path}/tmp/cache/")
-          [ :file_store, "#{root_path}/tmp/cache/" ]
+        if environment == 'development'
+          :no_store
         else
           :memory_store
         end
-- 
1.5.6.4