ActiveModel::Dirty#changes should return a HashWithIndifferentAccess [#…

…4157 state:resolved]

Keep the Rails style of inject

Signed-off-by: José Valim <jose.valim@gmail.com>

activemodel/lib/active_model/dirty.rb

@@ -107,7 +107,7 @@ def changed
     #   person.name = 'bob'
     #   person.changes # => { 'name' => ['bill', 'bob'] }
     def changes
-      changed.inject({}) { |h, attr| h[attr] = attribute_change(attr); h }
+      changed.inject(HashWithIndifferentAccess.new){ |h, attr| h[attr] = attribute_change(attr); h }
     end
 
     # Map of attributes that were changed when the model was saved.

activemodel/test/cases/dirty_test.rb

@@ -0,0 +1,29 @@
+require "cases/helper"
+
+class DirtyTest < ActiveModel::TestCase
+  class DirtyModel
+    include ActiveModel::Dirty
+    define_attribute_methods [:name]
+
+    def initialize
+      @name = nil
+    end
+
+    def name
+      @name
+    end
+
+    def name=(val)
+      name_will_change!
+      @name = val
+    end
+  end
+
+  test "changes accessible through both strings and symbols" do
+    model = DirtyModel.new
+    model.name = "David"
+    assert !model.changes[:name].nil?
+    assert !model.changes['name'].nil?
+  end
+
+end