_wp_utf8_codepoint_count( string $text, ?int $byte_offset = 0, ?int $max_byte_length = PHP_INT_MAX ): int

341function _wp_utf8_codepoint_count( string $text, ?int $byte_offset = 0, ?int $max_byte_length = PHP_INT_MAX ): int {342	if ( $byte_offset < 0 ) {343		return 0;344	}345 346	$count           = 0;347	$at              = $byte_offset;348	$end             = strlen( $text );349	$invalid_length  = 0;350	$max_byte_length = min( $end - $at, $max_byte_length );351 352	while ( $at < $end && ( $at - $byte_offset ) < $max_byte_length ) {353		$count += _wp_scan_utf8( $text, $at, $invalid_length, $max_byte_length - ( $at - $byte_offset ) );354		$count += $invalid_length > 0 ? 1 : 0;355		$at    += $invalid_length;356	}357 358	return $count;359}