src/Parser/ValueParser.php
private function parseString($value)
    {
        $single = false;
        $regex = self::REGEX_QUOTE_DOUBLE_STRING;
        $symbol = '"';

        if ($this->parser->string_helper->startsWith('\'', $value)) {
            $single = true;
            $regex =  self::REGEX_QUOTE_SINGLE_STRING;
            $symbol = "'";
        }

        $matches = $this->fetchStringMatches($value, $regex, $symbol);

        $value = trim($matches[0], $symbol);
        $value = strtr($value, self::$character_map);

        return ($single) ? $value : $this->variable_parser->parse($value, true);
    }
private function parseString($value)
    {
        $single = false;
        $regex = self::REGEX_QUOTE_DOUBLE_STRING;
        $symbol = '"';

        if ($this->parser->string_helper->startsWith('\'', $value)) {
            $single = true;
            $regex =  self::REGEX_QUOTE_SINGLE_STRING;
            $symbol = "'";
        }

        $matches = $this->fetchStringMatches($value, $regex, $symbol);

        $value = trim($matches[0], $symbol);
        $value = strtr($value, self::$character_map);

        return ($single) ? $value : $this->variable_parser->parse($value, true);
    }
Parses a .env string

@param string $value    The value to parse

@return string The parsed string