Fix CSV responses when index overriding with the call alias method

lib/active_admin/resource_controller/streaming.rb

@@ -15,6 +15,7 @@ def index
           yield(format) if block_given?
         end
       end
+      alias :index! :index
 
       protected
 

spec/unit/authorization/index_overriding_spec.rb

@@ -5,19 +5,44 @@
   before do
     load_resources { ActiveAdmin.register Post }
     @controller = Admin::PostsController.new
+  end
 
-    @controller.instance_eval do
-      def index
-        super do
-          render body: "Rendered from passed block"
-          return
+  context "with the call super" do
+    before do
+      @controller.instance_eval do
+        def index
+          super do |format|
+            format.html { render body: "Rendered from passed block" }
+          end
         end
       end
     end
+
+    it "should call block passed to overridden index" do
+      get :index
+      expect(response.body).to eq "Rendered from passed block"
+    end
+
+    it "can CSV responses" do
+      get :index, format: :csv
+      expect(response).to have_http_status :ok
+    end
   end
 
-  it "should call block passed to overridden index" do
-    get :index
-    expect(response.body).to eq "Rendered from passed block"
+  context "with the call alias method" do
+    before do
+      @controller.instance_eval do
+        def index
+          index! do
+            # Do nothing
+          end
+        end
+      end
+    end
+
+    it "can CSV responses" do
+      get :index, format: :csv
+      expect(response).to have_http_status :ok
+    end
   end
 end