title: Unit test validation for a Flask-WTF form
body: <p>I'm running a unit test for my "Register" function. Is there a way to check that all fields in the form had their validators satisfied upon submission?</p>
  
  <pre><code>def test_register(self):
      form = RegistrationForm()
      form.username.data = "test"
      form.email.data = "test@email.com"
  </code></pre>
  
  <p>My Registration form has a "SubmitField", I was wondering if there was a way to (within the unit test) simulate the "SubmitField" as clicked, and proceed to test whether validators for the username and email fields were satisfied using "AssertTrue()"?</p>