Source

File: wp-includes/class-wp-xmlrpc-server.php

protected function _prepare_comment( $comment ) {
		// Format page date.
		$comment_date_gmt = $this->_convert_date_gmt( $comment->comment_date_gmt, $comment->comment_date );

		if ( '0' == $comment->comment_approved ) {
			$comment_status = 'hold';
		} elseif ( 'spam' === $comment->comment_approved ) {
			$comment_status = 'spam';
		} elseif ( '1' == $comment->comment_approved ) {
			$comment_status = 'approve';
		} else {
			$comment_status = $comment->comment_approved;
		}
		$_comment = array(
			'date_created_gmt' => $comment_date_gmt,
			'user_id'          => $comment->user_id,
			'comment_id'       => $comment->comment_ID,
			'parent'           => $comment->comment_parent,
			'status'           => $comment_status,
			'content'          => $comment->comment_content,
			'link'             => get_comment_link( $comment ),
			'post_id'          => $comment->comment_post_ID,
			'post_title'       => get_the_title( $comment->comment_post_ID ),
			'author'           => $comment->comment_author,
			'author_url'       => $comment->comment_author_url,
			'author_email'     => $comment->comment_author_email,
			'author_ip'        => $comment->comment_author_IP,
			'type'             => $comment->comment_type,
		);

		/**
		 * Filters XML-RPC-prepared data for the given comment.
		 *
		 * @since 3.4.0
		 *
		 * @param array      $_comment An array of prepared comment data.
		 * @param WP_Comment $comment  Comment object.
		 */
		return apply_filters( 'xmlrpc_prepare_comment', $_comment, $comment );
	}