Update to drupal 8.0.0-rc1. For more information, see https://www.drupal.org/node/2582663

vendor/symfony/dom-crawler/Field/InputFormField.php

@@ -0,0 +1,47 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\DomCrawler\Field;
+
+/**
+ * InputFormField represents an input form field (an HTML input tag).
+ *
+ * For inputs with type of file, checkbox, or radio, there are other more
+ * specialized classes (cf. FileFormField and ChoiceFormField).
+ *
+ * @author Fabien Potencier <fabien@symfony.com>
+ *
+ * @api
+ */
+class InputFormField extends FormField
+{
+    /**
+     * Initializes the form field.
+     *
+     * @throws \LogicException When node type is incorrect
+     */
+    protected function initialize()
+    {
+        if ('input' !== $this->node->nodeName && 'button' !== $this->node->nodeName) {
+            throw new \LogicException(sprintf('An InputFormField can only be created from an input or button tag (%s given).', $this->node->nodeName));
+        }
+
+        if ('checkbox' === strtolower($this->node->getAttribute('type'))) {
+            throw new \LogicException('Checkboxes should be instances of ChoiceFormField.');
+        }
+
+        if ('file' === strtolower($this->node->getAttribute('type'))) {
+            throw new \LogicException('File inputs should be instances of FileFormField.');
+        }
+
+        $this->value = $this->node->getAttribute('value');
+    }
+}