Enable empty block comments

[adamsilverstein]

Trac ticket:

---

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We can introduce this in GB using allow_empty_comment

[github-actions]

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[adamsilverstein]

Thanks for reviewing @dream-encode! We will start with a matching Trac ticket then I can get it committed.

[adamsilverstein]

cc: @TimothyBJacobs for review

[github-actions]

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Props adamsilverstein, davidbaumwald, kadamwhite.

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[adamsilverstein]

Looking at this again I see we already do an empty content check in check_is_comment_content_allowed and allow bypassing with a filter:

wordpress-develop/src/wp-includes/rest-api/endpoints/class-wp-rest-comments-controller.php

Lines 1918 to 1929 in 7289643

	/** This filter is documented in wp-includes/comment.php */
	$allow_empty = apply_filters( 'allow_empty_comment', false, $check );
	if ( $allow_empty ) {
	return true;
	}
	/*
	* Do not allow a comment to be created with missing or empty
	* comment_content. See wp_handle_comment_submission().
	*/
	return '' !== $check['comment_content'];

Maybe we can just remove the additional check here? That way Gutenberg can bypass the check for its specific types using the allow_empty_comment filter.

[kadamwhite]

@TimothyBJacobs I'm looking at the history here on how core's handled empty comments historically, and can make the trac ticket Adam's asked for

[adamsilverstein]

Closing this for now, will revisit once we have a Trac ticket and direction in the Gutenberg plugin.