diff --git a/test/unit/custom_workflow_mailer_test.rb b/test/unit/custom_workflow_mailer_test.rb
index d54e832..73623a4 100644
--- a/test/unit/custom_workflow_mailer_test.rb
+++ b/test/unit/custom_workflow_mailer_test.rb
@@ -42,8 +42,8 @@ def test_truth
   def test_custom_email
     CustomWorkflowMailer.deliver_custom_email @user2, subject: 'Subject', text_body: 'Body', html_body: 'Body'
     email = last_email
-    assert text_part(email).body.include? 'Body', text_part(email).body
-    assert html_part(email).body.include? 'Body', html_part(email).body
+    assert text_part(email).body.include?('Body'), text_part(email).body
+    assert html_part(email).body.include?('Body'), html_part(email).body
   end
 
   private