Tidy up

test/action_view_extensions/form_helper_test.rb

@@ -103,12 +103,7 @@ class FormHelperTest < ActionView::TestCase
   end
 
   test 'custom error proc is not destructive' do
-    previous_error_proc = ActionView::Base.field_error_proc
-
-    begin
-      expected_error_proc = lambda {}
-      ActionView::Base.field_error_proc = expected_error_proc
-
+    swap_field_error_proc do
       result = nil
       simple_form_for :user do |f|
         result = simple_fields_for 'address' do
@@ -117,33 +112,29 @@ class FormHelperTest < ActionView::TestCase
       end
 
       assert_equal 'hello', result
-      assert_equal expected_error_proc, ActionView::Base.field_error_proc
-
-    ensure
-      ActionView::Base.field_error_proc = previous_error_proc
     end
   end
 
   test 'custom error proc survives an exception' do
-    previous_error_proc = ActionView::Base.field_error_proc
-
-    begin
-      expected_error_proc = lambda {}
-      ActionView::Base.field_error_proc = expected_error_proc
-
+    swap_field_error_proc do
       begin
         simple_form_for :user do |f|
           simple_fields_for 'address' do
             raise 'an exception'
           end
         end
-      rescue StandardError => e
+      rescue StandardError
       end
+    end
+  end
 
-      assert_equal expected_error_proc, ActionView::Base.field_error_proc
+  private
 
-    ensure
-      ActionView::Base.field_error_proc = previous_error_proc
+  def swap_field_error_proc(expected_error_proc = lambda {})
+    swap ActionView::Base, :field_error_proc => expected_error_proc do
+      yield
+
+      assert_equal expected_error_proc, ActionView::Base.field_error_proc
     end
   end
 end