enable-venue-comments.php

/**
 * Helper to let users comment on venues.
 *
 *     - Discussion must be enabled via WP settings
 *     - Default page template is recommended
 *     - Success is, to a degree, theme dependent!
 *
 * To launch, call VenueCommments::enable(). Note that this was written against
 * The Events Calendar/Events Calendar PRO 3.9.3 - in future releases this may
 * not be required or different strategies may need to be employed.
 */
class VenueComments {
	protected $template = '';


	public static function enable() {
		return new self();
	}

	public function __construct() {
		add_action( 'init', array( $this, 'setup' ), 20 );
	}

	public function setup() {
		if ( ! class_exists( 'TribeEvents' ) ) return;
		add_post_type_support( TribeEvents::VENUE_POST_TYPE, 'comments' );
		add_action( 'wp_head', array( $this, 'on_venue_post' ) );
	}

	public function on_venue_post() {
		if ( ! is_singular( TribeEvents::VENUE_POST_TYPE ) ) return;
		add_filter( 'comments_open', array( $this, 'restore_venue_object' ) );
		add_filter( 'comments_template', array( $this, 'capture' ), 5   );
		add_filter( 'comments_template', array( $this, 'restore' ), 50  );
		add_filter( 'comments_template', array( $this, 'restore' ), 500 ); // Double hooked deliberately!
	}

	public function capture( $path ) {
		$this->template = $path;
	}

	public function restore( $path ) {
		return empty( $this->template ) ? $path : $this->template;
	}

	public function restore_venue_object( $status ) {
		$GLOBALS['post'] = get_post( tribe_get_venue_id() );
		return $status;
	}
}

VenueComments::enable();

Notes:

• We double-hook on comments_template because TEC code unhooks a callback on the same action - a core WP bug means our own comments_template callback would otherwise be skipped
• We restore the venue post object since otherwise the final comments form will relate to the last listed upcoming event for that venue
• Successfully tested with TEC/ECP 3.9.3, WP 4.2.2 and Twenty Fifteen default theme - default page template must be enabled in the event settings