refactor Reference to a ClassCache object, fix lazy lookup in Middleware so that anonymous classes are supported

4 files changed, 122 insertions, 14 deletions

diff --git a/activesupport/CHANGELOG b/activesupport/CHANGELOG
index 1b8bcf649c..99cea2586b 100644
--- a/activesupport/CHANGELOG
+++ b/activesupport/CHANGELOG
@@ -1,5 +1,11 @@
 *Rails 3.1.0 (unreleased)*
 
+* ActiveSupport::Dependencies::ClassCache class has been introduced for
+holding references to reloadable classes.
+
+* ActiveSupport::Dependencies::Reference has been refactored to take direct
+advantage of the new ClassCache.
+
 * Backports Range#cover? as an alias for Range#include? in Ruby 1.8 [Diego Carrion, fxn]
 
 * Added weeks_ago and prev_week to Date/DateTime/Time. [Rob Zolkos, fxn]
diff --git a/activesupport/lib/active_support/dependencies.rb b/activesupport/lib/active_support/dependencies.rb
index dab6fdbac6..94a8608aeb 100644
--- a/activesupport/lib/active_support/dependencies.rb
+++ b/activesupport/lib/active_support/dependencies.rb
@@ -524,31 +524,52 @@ module ActiveSupport #:nodoc:
       explicitly_unloadable_constants.each { |const| remove_constant const }
     end
 
-    class Reference
-      @@constants = Hash.new { |h, k| h[k] = Inflector.constantize(k) }
+    class ClassCache
+      def initialize
+        @store = Hash.new { |h, k| h[k] = Inflector.constantize(k) }
+      end
+
+      def empty?
+        @store.empty?
+      end
+
+      def key?(key)
+        @store.key?(key)
+      end
 
-      attr_reader :name
+      def []=(key, value)
+        return unless key.respond_to?(:name)
 
-      def initialize(name)
-        @name = name.to_s
-        @@constants[@name] = name if name.respond_to?(:name)
+        raise(ArgumentError, 'anonymous classes cannot be cached') unless key.name
+
+        @store[key.name] = value
+      end
+
+      def [](key)
+        key = key.name if key.respond_to?(:name)
+
+        @store[key]
       end
+      alias :get :[]
 
-      def get
-        @@constants[@name]
+      def new(name)
+        self[name] = name
+        self
       end
 
-      def self.clear!
-        @@constants.clear
+      def clear!
+        @store.clear
       end
     end
 
+    Reference = ClassCache.new
+
     def ref(name)
       references[name] ||= Reference.new(name)
     end
 
     def constantize(name)
-      ref(name).get
+      ref(name).get(name)
     end
 
     # Determine if the given constant has been automatically loaded.
diff --git a/activesupport/test/class_cache_test.rb b/activesupport/test/class_cache_test.rb
new file mode 100644
index 0000000000..3d3ae559e5
--- /dev/null
+++ b/activesupport/test/class_cache_test.rb
@@ -0,0 +1,81 @@
+require 'abstract_unit'
+require 'active_support/dependencies'
+
+module ActiveSupport
+  module Dependencies
+    class ClassCacheTest < ActiveSupport::TestCase
+      def setup
+        @cache = ClassCache.new
+      end
+
+      def test_empty?
+        assert @cache.empty?
+        @cache[ClassCacheTest] = ClassCacheTest
+        assert !@cache.empty?
+      end
+
+      def test_clear!
+        assert @cache.empty?
+        @cache[ClassCacheTest] = ClassCacheTest
+        assert !@cache.empty?
+        @cache.clear!
+        assert @cache.empty?
+      end
+
+      def test_set_key
+        @cache[ClassCacheTest] = ClassCacheTest
+        assert @cache.key?(ClassCacheTest.name)
+      end
+
+      def test_set_rejects_strings
+        @cache[ClassCacheTest.name] = ClassCacheTest
+        assert @cache.empty?
+      end
+
+      def test_get_with_class
+        @cache[ClassCacheTest] = ClassCacheTest
+        assert_equal ClassCacheTest, @cache[ClassCacheTest]
+      end
+
+      def test_get_with_name
+        @cache[ClassCacheTest] = ClassCacheTest
+        assert_equal ClassCacheTest, @cache[ClassCacheTest.name]
+      end
+
+      def test_get_constantizes
+        assert @cache.empty?
+        assert_equal ClassCacheTest, @cache[ClassCacheTest.name]
+      end
+
+      def test_get_is_an_alias
+        assert_equal @cache[ClassCacheTest], @cache.get(ClassCacheTest.name)
+      end
+
+      def test_new
+        @cache.new ClassCacheTest
+        assert @cache.key?(ClassCacheTest.name)
+      end
+
+      def test_new_rejects_strings
+        @cache.new ClassCacheTest.name
+        assert !@cache.key?(ClassCacheTest.name)
+      end
+
+      def test_new_returns_self
+        v = @cache.new ClassCacheTest.name
+        assert_equal @cache, v
+      end
+
+      def test_anonymous_class_fail
+        assert_raises(ArgumentError) do
+          @cache.new Class.new
+        end
+
+        assert_raises(ArgumentError) do
+          x = Class.new
+          @cache[x] = x
+        end
+      end
+    end
+  end
+end
diff --git a/activesupport/test/dependencies_test.rb b/activesupport/test/dependencies_test.rb
index bc7f597f1d..b3ada53497 100644
--- a/activesupport/test/dependencies_test.rb
+++ b/activesupport/test/dependencies_test.rb
@@ -479,13 +479,13 @@ class DependenciesTest < Test::Unit::TestCase
     with_loading 'dependencies' do
       c = ActiveSupport::Dependencies.ref("ServiceOne")
       service_one_first = ServiceOne
-      assert_equal service_one_first, c.get
+      assert_equal service_one_first, c.get("ServiceOne")
       ActiveSupport::Dependencies.clear
       assert ! defined?(ServiceOne)
 
       service_one_second = ServiceOne
-      assert_not_equal service_one_first, c.get
-      assert_equal service_one_second, c.get
+      assert_not_equal service_one_first, c.get("ServiceOne")
+      assert_equal service_one_second, c.get("ServiceOne")
     end
   end