[php-src] Issue #10203: New function mb_str_pad (multibyte str_pad)

Issue: https://github.com/php/php-src/issues/10203 Author: aetonsi ### Description Hello, I'd like to propose a new function. Amidst all of the mb_*** versions of the string functions, i noticed that one is missing: str_pad. Something that would allow to do this: ```php mb_str_pad('▶▶', 6, '❤❓❇', STR_PAD_RIGHT); mb_str_pad('▶▶', 6, '❤❓❇', STR_PAD_LEFT); mb_str_pad('▶▶', 6, '❤❓❇', STR_PAD_BOTH); ``` and get this ```log ▶▶❤❓❇❤ ❤❓❇❤▶▶ ❤❓▶▶❤❓ ``` It could be as simple as this: ```php function mb_str_pad( string $string, int $length, string $pad_string = " ", int $pad_type = STR_PAD_RIGHT, string|null $encoding = null ) { $padding = ''; $paddingLength = $length - mb_strlen($string, $encoding); while (($l = mb_strlen($padding, $encoding)) < $paddingLength) { // build padding string 1 $pad_string at a time until the desired $paddingLength is reached $padding .= mb_substr($pad_string, 0, $paddingLength - $l, $encoding); } return match ($pad_type) { STR_PAD_RIGHT => $string . $padding, STR_PAD_LEFT => $padding . $string, STR_PAD_BOTH => mb_substr($padding, 0, ceil(mb_strlen($padding, $encoding) / 2)) . $string . mb_substr($padding, 0, floor(mb_strlen($padding, $encoding) / 2)), }; } ``` ...obviously this is just an example, it's not optimized, it doesn't consider errors, etc --- Have a nice day