Function jsSprintf

bin/yarn-standalone.js:112809–112910

(fmt)

 * numbers, non-decimal numbers, and characters.
 */
function jsSprintf(fmt)
{
	var regex = [
	    '([^%]*)',				/* normal text */
	    '%',				/* start of format */
	    '([\'\\-+ #0]*?)',			/* flags (optional) */
	    '([1-9]\\d*)?',			/* width (optional) */
	    '(\\.([1-9]\\d*))?',		/* precision (optional) */
	    '[lhjztL]*?',			/* length mods (ignored) */
	    '([diouxXfFeEgGaAcCsSp%jr])'	/* conversion */
	].join('');

	var re = new RegExp(regex);
	var args = Array.prototype.slice.call(arguments, 1);
	var flags, width, precision, conversion;
	var left, pad, sign, arg, match;
	var ret = '';
	var argn = 1;

	mod_assert.equal('string', typeof (fmt));

	while ((match = re.exec(fmt)) !== null) {
		ret += match[1];
		fmt = fmt.substring(match[0].length);

		flags = match[2] || '';
		width = match[3] || 0;
		precision = match[4] || '';
		conversion = match[6];
		left = false;
		sign = false;
		pad = ' ';

		if (conversion == '%') {
			ret += '%';
			continue;
		}

		if (args.length === 0)
			throw (new Error('too few args to sprintf'));

		arg = args.shift();
		argn++;

		if (flags.match(/[\' #]/))
			throw (new Error(
			    'unsupported flags: ' + flags));

		if (precision.length > 0)
			throw (new Error(
			    'non-zero precision not supported'));

		if (flags.match(/-/))
			left = true;

		if (flags.match(/0/))
			pad = '0';