Investigate removing the inner div in form.html.twig

I'm agree with you. RTBC

I'm going to commit this template to the front-end branch with the inner div (even though I agree with you). The comment in form.inc indicates that the div inside the form is required for XHTML compliance, can someone please confirm that removing it won't get us in trouble?

I'll add a TODO in the template so we can revisit the div removal, after someone does some research on compliance, since I dunno anything about it :)

For background on the DIV inside the FORM element, see #690980: Disabled form elements not properly rendered.

I just scanned #690980: Disabled form elements not properly rendered, and could find no reference about the inner div. Additionally, investigating one of the patches on that issue, even though that line was changed, it looks like the inner div existed before that issue.

From http://drupal.org/files/issues/drupal.form-disabled.102.patch

-  return '<form '. $action .' method="'. $element['#method'] .'" id="'. $element['#id'] .'"'. drupal_attributes($element['#attributes']) .">\n<div>". $element['#children'] ."\n</div></form>\n";
+  $element['#attributes']['id'] = $element['#id'];
+  // Anonymous DIV to satisfy XHTML compliance.
+  return '<form' . drupal_attributes($element['#attributes']) . '><div>' . $element['#children'] . '</div></form>';
 }

We still need to find out where the inner DIV was introduced, and read about why.

A quick search through the git history turned up a commit eb030cb9d8839bd08cb2bd1e4f954efe37047303 from 2003 when the inner DIV was first added, whose commit message was "Improvements: XHTML-ifications. Patch by GmbH.", so it could be that the inner div was for Xhtml compliance.

I used git log -S\</div\>\</form\> to search the git history.

My guess, from studying the XHTML DTD is that the inner div is there to ensure that you get valid XHTML, because <form><input/></form> (according to the XHTML dtd, is invalid), but <form><div><input/></div></form> is valid.

<!ELEMENT form %form.content;>

<!ENTITY % form.content "(%block; | %misc;)*">

<!ENTITY % misc "noscript | %misc.inline;">
<!ENTITY % misc.inline "ins | del | script">

<!ENTITY % block "p | %heading; | div | %lists; | %blocktext; | fieldset | table">

<!ENTITY % heading "h1|h2|h3|h4|h5|h6">
<!ENTITY % lists "ul | ol | dl">
<!ENTITY % blocktext "pre | hr | blockquote | address">

In plain english, the only valid elements inside the FORM tag include:

NOSCRIPT, INS, DEL, SCRIPT, P, H1-6, DIV, UL/OL/DL, PRE, HR, BLOCKQUOTE, ADDRESS, FIELDSET, TABLE.

and, INPUT is not a tag in that list.

On the other hand, the HTML 5.1 nightly draft specifically shows an example HTML snippet in the section about the form element that uses: <form><label><input></form>.

Does anyone know what is the official stance for XHTML support in Drupal 8?