I'm calling out for you to decide how to resolve the inconsistency between theForm::isValid() method and thevalid variable available in the template:

• isValid() returnsfalse if a form was not submitted. This way it is possible to write concise controller code:

$form =$this->createForm(...);$form->handleRequest($request);if ($form->isValid()) {// only executed if the form is submitted AND valid}

• valid containstrue if a form was not submitted. This way it is possible to rely on this variable for error styling of a form.

<div{%ifnotform.vars.valid %}class="error"{%endif %}>

We have two alternatives for resolving this problem:

1. Leave the inconsistency as is.
2. MakeisValid() returntrue if a form was not submitted (consistent withvalid)
3. Revert to the 2.2 behavior of throwing an exception ifisValid() is called on a non-submitted form (not consistent withvalid).

Both 2. and 3. will require additional code in the controller:

$form =$this->createForm(...);$form->handleRequest($request);if ($form->isSubmitted() &&$form->isValid()) {// only executed if the form is submitted AND valid}

What do you think?