BaseControl: added 'form' attribute

src/Forms/Controls/BaseControl.php

@@ -239,6 +239,7 @@ public function getControl()
 			'required' => $this->isRequired(),
 			'disabled' => $this->isDisabled(),
 			'data-nette-rules' => Nette\Forms\Helpers::exportRules($this->rules) ?: null,
+			'form' => $el->form ?? $this->getForm()->getElementPrototype()->id,
 		]);
 	}
 

src/Forms/Controls/Button.php

@@ -59,9 +59,11 @@ public function getControl(string|Stringable|null $caption = null): Html
 	{
 		$this->setOption('rendered', true);
 		$caption = $this->translate($caption ?? $this->getCaption());
-		$el = (clone $this->control)->addAttributes([
+		$el = clone $this->control;
+		$el->addAttributes([
 			'name' => $this->getHtmlName(),
 			'disabled' => $this->isDisabled(),
+			'form' => $el->form ?? $this->getForm()->getElementPrototype()->id,
 		]);
 		if ($caption instanceof Html || ($caption !== null && $el->getName() === 'button')) {
 			$el->setName('button')->setText($caption);

src/Forms/Controls/HiddenField.php

@@ -84,6 +84,7 @@ public function getControl(): Html
 			'name' => $this->getHtmlName(),
 			'disabled' => $this->isDisabled(),
 			'value' => (string) $this->value,
+			'form' => $el->form ?? $this->getForm()->getElementPrototype()->id,
 		]);
 	}
 

tests/Forms/Forms.form.phpt

@@ -0,0 +1,31 @@
+<?php
+
+declare(strict_types=1);
+
+use Nette\Forms\Form;
+use Tester\Assert;
+
+require __DIR__ . '/../bootstrap.php';
+
+
+$form = new Form;
+$form->getElementPrototype()->id = 'frmid';
+
+$form->addText('a');
+$form->addTextArea('b');
+$form->addDate('c');
+$form->addUpload('d');
+$form->addHidden('e');
+$form->addCheckbox('f');
+$form->addRadioList('g', null, ['item']);
+$form->addCheckboxList('h', null, ['item']);
+$form->addSelect('i');
+$form->addMultiSelect('j');
+$form->addColor('k');
+$form->addSubmit('l');
+$form->addButton('m');
+$form->addImageButton('n');
+$form->addHidden('none')->setHtmlAttribute('form', false);
+$form->addHidden('diff')->setHtmlAttribute('form', 'different');
+
+Assert::matchFile(__DIR__ . '/expected/Forms.form.expect', $form->__toString(true));

tests/Forms/expected/Forms.form.expect

@@ -0,0 +1,72 @@
+<form action="" method="post" id="frmid" enctype="multipart/form-data">
+
+<table>
+<tr>
+	<th><label for="frm-a"></label></th>
+
+	<td><input type="text" name="a" id="frm-a" form="frmid" class="text"></td>
+</tr>
+
+<tr>
+	<th><label for="frm-b"></label></th>
+
+	<td><textarea name="b" id="frm-b" form="frmid"></textarea></td>
+</tr>
+
+<tr>
+	<th><label for="frm-c"></label></th>
+
+	<td><input type="date" name="c" id="frm-c" form="frmid"></td>
+</tr>
+
+<tr>
+	<th><label for="frm-d"></label></th>
+
+	<td><input type="file" name="d" id="frm-d" data-nette-rules='[{"op":":fileSize","msg":"The size of the uploaded file can be up to 52428800 bytes.","arg":52428800}]' form="frmid" class="text"></td>
+</tr>
+
+<tr>
+	<th></th>
+
+	<td><label for="frm-f"><input type="checkbox" name="f" id="frm-f" form="frmid"></label></td>
+</tr>
+
+<tr>
+	<th><label></label></th>
+
+	<td><label><input type="radio" name="g" form="frmid" value="0">item</label></td>
+</tr>
+
+<tr>
+	<th><label></label></th>
+
+	<td><label><input type="checkbox" name="h[]" form="frmid" value="0">item</label></td>
+</tr>
+
+<tr>
+	<th><label for="frm-i"></label></th>
+
+	<td><select name="i" id="frm-i" form="frmid"></select></td>
+</tr>
+
+<tr>
+	<th><label for="frm-j"></label></th>
+
+	<td><select name="j[]" id="frm-j" form="frmid" multiple></select></td>
+</tr>
+
+<tr>
+	<th><label for="frm-k"></label></th>
+
+	<td><input type="color" name="k" id="frm-k" form="frmid" value="#000000"></td>
+</tr>
+
+<tr>
+	<th></th>
+
+	<td><input type="submit" name="l" form="frmid" class="button"> <input type="button" name="m" form="frmid" class="button"> <input type="image" name="n[]" form="frmid" class="imagebutton"></td>
+</tr>
+</table>
+
+<input type="hidden" name="e" value="" form="frmid"><input type="hidden" name="none" value=""><input type="hidden" name="diff" form="different" value="">
+</form>