Broken custom delimiters when combined with { } at 3.1.32

[RYRDU]

I want to use this style delimiters

$smarty->left_delimiter = '{^';
$smarty->right_delimiter = '^}';

This will produce the following exception
Line 357 at file: smarty\libs\sysplugins\smarty_internal_templatelexer.php

I am positive everything was working fine at 3.1.31

I try to solve the problem, so I edited the function initDelimiterPreg in smarty_internal_templatecompilerbase.php

/**
 * Build lexer regular expressions for left and right delimiter and user defined literals
 */
public function initDelimiterPreg()
{
    $ldel = $this->smarty->getLeftDelimiter();
    $this->ldelLength = strlen($ldel);
    $this->ldelPreg = '';
    foreach (str_split($ldel, 1) as $chr) {
        $chr = preg_quote($chr, '/');
        $this->ldelPreg .= '[' . ($chr === '\\' ? '\\' : '') . $chr . ']';
    }

    $rdel = $this->smarty->getRightDelimiter();
    $this->rdelLength = strlen($rdel);
    $this->rdelPreg = '';
    foreach (str_split($rdel, 1) as $chr) {
        $chr = preg_quote($chr, '/');
        $this->rdelPreg .= '[' . ($chr === '\\' ? '\\' : '') . $chr . ']';
    }
    $literals = $this->smarty->getLiterals();
    if (!empty($literals)) {
        foreach ($literals as $key => $literal) {
            $literalPreg = '';
            foreach (str_split($literal, 1) as $chr) {
                $literalPreg .= '[' . ($chr === '\\' ? '\\' : '') . $chr . ']';
            }
            $literals[ $key ] = $literalPreg;
        }
        $this->literalPreg = '|' . implode('|', $literals);
    } else {
        $this->literalPreg = '';
    }
}

[artemsuv]

Make pull request #482