add Form with empty POST test

Author: mvorisek

demos/_unit-test/form-empty.php

@@ -0,0 +1,17 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Atk4\Ui\Demos;
+
+use Atk4\Ui\Form;
+use Atk4\Ui\Js\JsToast;
+
+/** @var \Atk4\Ui\App $app */
+require_once __DIR__ . '/../init-app.php';
+
+$form = Form::addTo($app);
+
+$form->onSubmit(static function (Form $form) {
+    return new JsToast('Post ' . ($form->getApp()->getRequest()->getParsedBody() === [] ? 'ok' : 'unexpected'));
+});

src/Form.php

@@ -521,6 +521,7 @@ public function setupAjaxSubmit(): void
             'on' => 'submit',
             'url' => $this->cb->getJsUrl(),
             'method' => 'POST',
+            'contentType' => 'application/x-www-form-urlencoded; charset=UTF-8', // remove once https://github.com/jquery/jquery/issues/5346 is fixed
             'serializeForm' => true,
         ], $this->apiConfig));
 

tests-behat/form.feature

@@ -84,3 +84,8 @@ Feature: Form
     When I click using selector "//label[text()='I am a developer']"
     Then I should not see "Check all language that apply"
     Then I should not see "Css"
+
+  Scenario: empty POST
+    Given I am on "_unit-test/form-empty.php"
+    When I press button "Save"
+    Then Toast display should contain text "Post ok"