Post Comment button disappeared in some themes

[SergeyBiryukov]

[31699] caused the Post Comment button to disappear in some themes.

As reported by @tellyworth in 33:ticket:15015:

Just FYI we've come across a handful of themes that were affected by this. They were filtering comment_form_defaults and building a fresh $args array from scratch, so the new submit elements were not included in the return. That left them with no Submit Comment button.

Seeing some similar reports on support forums. Here's an ​example in ​My Life theme.

We should make sure that 'submit_button' and 'submit_field' are still in the array after it's filtered.

[boonebgorges]

We should make sure that 'submit_button' and 'submit_field' are still in the array after it's filtered.

32312.diff​ enforces this for *all* default values. This seems like a more general solution for this problem. The only backward compatibility concern would be isset() checks expecting a given array key to be missing after filtering the default arguments. I don't see anything like that in comment_form(), and $args is never passed to a hook that might do a similar trick, but it would be nice to get another set of eyes.

[anneastrid15]

I have that same problem with the Origin Theme. Please fix in next WP update.

[SergeyBiryukov]

Replying to boonebgorges:

The only backward compatibility concern would be isset() checks expecting a given array key to be missing after filtering the default arguments. I don't see anything like that in comment_form(), and $args is never passed to a hook that might do a similar trick, but it would be nice to get another set of eyes.

This would no longer work with the array_merge():

function mytheme_comments_form_defaults( $defaults ) {
	unset( $defaults['comment_notes_after'] );
	return $defaults;
}
add_filter( 'comment_form_defaults', 'mytheme_comments_form_defaults' );

But it currently produces a notice anyway, and there's a more correct way to do it:

function mytheme_comments_form_defaults( $defaults ) {
	$defaults['comment_notes_after'] = '';
	return $defaults;
}
add_filter( 'comment_form_defaults', 'mytheme_comments_form_defaults' );

So I'd suggest going with your fix.

[SergeyBiryukov]

In 32511:

In comment_form(), ensure that filtered arguments contain all required default values.

props boonebgorges.
fixes #32312 for trunk.

[jonna]

Replying to boonebgorges:

32312.diff​ enforces this for *all* default values.

Simply applying the first part of your patch (to lines 2255-2257 of comment-template.php) fixed the issue for me.

[pento]

In 33307:

In comment_form(), ensure that filtered arguments contain all required default values.

Merge of [32511] to the 4.2 branch.

Props boonebgorges.
Fixes #32312.