WP_Block_Processor::next_token(): bool

736	public function next_token(): bool {737		if ( $this->last_error || self::COMPLETE === $this->state || self::INCOMPLETE_INPUT === $this->state ) {738			return false;739		}740 741		// Void tokens automatically pop off the stack of open blocks.742		if ( $this->was_void ) {743			array_pop( $this->open_blocks_at );744			array_pop( $this->open_blocks_length );745			$this->was_void = false;746		}747 748		$text = $this->source_text;749		$end  = strlen( $text );750 751		/*752		 * Because HTML spans are inferred after finding the next delimiter, it means that753		 * the parser must transition out of that HTML state and reuse the token boundaries754		 * it found after the HTML span. If those boundaries are before the end of the755		 * document it implies that a real delimiter was found; otherwise this must be the756		 * terminating HTML span and the parsing is complete.757		 */758		if ( self::HTML_SPAN === $this->state ) {759			if ( $this->matched_delimiter_at >= $end ) {760				$this->state = self::COMPLETE;761				return false;762			}763 764			switch ( $this->next_stack_op ) {765				case 'void':766					$this->was_void             = true;767					$this->open_blocks_at[]     = $this->namespace_at;768					$this->open_blocks_length[] = $this->name_at + $this->name_length - $this->namespace_at;769					break;770 771				case 'push':772					$this->open_blocks_at[]     = $this->namespace_at;773					$this->open_blocks_length[] = $this->name_at + $this->name_length - $this->namespace_at;774					break;775 776				case 'pop':777					array_pop( $this->open_blocks_at );778					array_pop( $this->open_blocks_length );779					break;780			}781 782			$this->next_stack_op = null;783			$this->state         = self::MATCHED;784			return true;785		}786 787		$this->state          = self::READY;788		$after_prev_delimiter = $this->matched_delimiter_at + $this->matched_delimiter_length;789		$at                   = $after_prev_delimiter;790 791		while ( $at < $end ) {792			/*793			 * Find the next possible start of a delimiter.794			 *795			 * This follows the behavior in the official block parser, which segments a post796			 * by the block comment delimiters. It is possible for an HTML attribute to contain797			 * what looks like a block comment delimiter but which is actually an HTML attribute798			 * value. In such a case, the parser here will break apart the HTML and create the799			 * block boundary inside the HTML attribute. In other words, the block parser800			 * isolates sections of HTML from each other, even if that leads to malformed markup.801			 *802			 * For a more robust parse, scan through the document with the HTML API and parse803			 * comments once they are matched to see if they are also block delimiters. In804			 * practice, this nuance has not caused any known problems since developing blocks.805			 *806			 * <⃨!⃨-⃨-⃨ /wp:core/paragraph {"dropCap":true} /-->807			 */808			$comment_opening_at = strpos( $text, '<!--', $at );809 810			/*811			 * Even if the start of a potential block delimiter is not found, the document812			 * might end in a prefix of such, and in that case there is incomplete input.813			 */814			if ( false === $comment_opening_at ) {815				if ( str_ends_with( $text, '<!-' ) ) {