Lowercasing filenames

[darrylhein]

Our clients upload files with all manner of filenames so it'd be nice to have them cleaned up a bit more. We have the convertFilenamesToAscii option enabled, which helps, but we'd also like to have them lowercased. This especially helpful if using a case sensitive fs or web server.

I'd be happy to take a crack at a PR.

It seems like it'd be an additional option on #

cms/src/helpers/FileHelper.php

Lines 201 to 291 in d4c5f81

	/**
	* Sanitizes a filename.
	*
	* @param string $filename the filename to sanitize
	* @param array $options options for sanitization. Valid options are:
	* - `asciiOnly`: bool, whether only ASCII characters should be allowed. Defaults to false.
	* - `separator`: string|null, the separator character to use in place of whitespace. defaults to '-'. If set to null, whitespace will be preserved.
	* @return string The cleansed filename
	*/
	public static function sanitizeFilename(string $filename, array $options = []): string
	{
	$asciiOnly = $options['asciiOnly'] ?? false;
	$separator = array_key_exists('separator', $options) ? $options['separator'] : '-';
	$disallowedChars = [
	'—',
	'–',
	'‘',
	'’',
	'“',
	'”',
	'–',
	'—',
	'+',
	'%',
	'^',
	'~',
	'?',
	'[',
	']',
	'/',
	'\\',
	'=',
	'<',
	'>',
	':',
	';',
	',',
	'\'',
	'"',
	'&',
	'$',
	'#',
	'*',
	'(',
	')',
	'|',
	'~',
	'`',
	'!',
	'{',
	'}',
	];
	// Replace any control characters in the name with a space.
	$filename = preg_replace("/\\x{00a0}/iu", ' ', $filename);
	// Remove invisible chars from the filename
	// https://github.com/craftcms/cms/issues/12741
	$filename = preg_replace(StringHelper::invisibleCharsRegex(), '', $filename);
	// Strip any characters not allowed.
	$filename = str_replace($disallowedChars, '', strip_tags($filename));
	if (!Craft::$app->getDb()->getSupportsMb4()) {
	// Strip emojis
	$filename = StringHelper::replaceMb4($filename, '');
	}
	// Nuke any trailing or leading .-_
	$filename = trim($filename, '.-_');
	if ($asciiOnly) {
	try {
	// Always use the primary site language, so file paths/names are normalized
	// to ASCII consistently regardless of who is logged in.
	$language = Craft::$app->getSites()->getPrimarySite()->language;
	} catch (SiteNotFoundException $e) {
	$language = Craft::$app->language;
	}
	$filename = StringHelper::toAscii($filename, $language);
	}
	if ($separator !== null) {
	$qSeparator = preg_quote($separator, '/');
	$filename = preg_replace("/[\s$qSeparator]+/u", $separator, $filename);
	$filename = preg_replace("/^$qSeparator+|$qSeparator+$/u", '', $filename);
	}
	return $filename;
	}

along with an additional config option.