base.rb in actionmailer-6.0.0.rc1

- old
+ new

@@ -942,13 +942,13 @@
         assignable = headers.except(:parts_order, :content_type, :body, :template_name,
                                     :template_path, :delivery_method, :delivery_method_options)
         assignable.each { |k, v| message[k] = v }
       end
 
-      def collect_responses(headers)
+      def collect_responses(headers, &block)
         if block_given?
-          collect_responses_from_block(headers, &Proc.new)
+          collect_responses_from_block(headers, &block)
         elsif headers[:body]
           collect_responses_from_text(headers)
         else
           collect_responses_from_templates(headers)
         end
@@ -971,13 +971,13 @@
       def collect_responses_from_templates(headers)
         templates_path = headers[:template_path] || self.class.mailer_name
         templates_name = headers[:template_name] || action_name
 
         each_template(Array(templates_path), templates_name).map do |template|
-          self.formats = [template.format]
+          format = template.format || self.formats.first
           {
-            body: render(template: template),
-            content_type: template.type.to_s
+            body: render(template: template, formats: [format]),
+            content_type: Mime[format].to_s
           }
         end
       end
 
       def each_template(paths, name, &block)