core-bundle/src/Config/Loader/PhpFileLoader.php
private function parseFile(string $file): array
    {
        $code = '';
        $namespace = '';
        $buffer = false;
        $stream = new \PHP_Token_Stream($file);

        foreach ($stream as $token) {
            switch (true) {
                case $token instanceof \PHP_Token_OPEN_TAG:
                case $token instanceof \PHP_Token_CLOSE_TAG:
                    // remove
                    break;

                case false !== $buffer:
                    $buffer .= $token;

                    if (';' === (string) $token) {
                        $code .= $this->handleDeclare($buffer);
                        $buffer = false;
                    }
                    break;

                case $token instanceof \PHP_Token_NAMESPACE:
                    if ('{' === $token->getName()) {
                        $namespace = false;
                        $code .= $token;
                    } else {
                        $namespace = $token->getName();
                        $stream->seek($token->getEndTokenId());
                    }
                    break;

                case $token instanceof \PHP_Token_DECLARE:
                    $buffer = (string) $token;
                    break;

                default:
                    $code .= $token;
            }
        }

        return [$code, $namespace];
    }
private function parseFile(string $file): array
    {
        $code = '';
        $namespace = '';
        $buffer = false;
        $stream = new \PHP_Token_Stream($file);

        foreach ($stream as $token) {
            switch (true) {
                case $token instanceof \PHP_Token_OPEN_TAG:
                case $token instanceof \PHP_Token_CLOSE_TAG:
                    // remove
                    break;

                case false !== $buffer:
                    $buffer .= $token;

                    if (';' === (string) $token) {
                        $code .= $this->handleDeclare($buffer);
                        $buffer = false;
                    }
                    break;

                case $token instanceof \PHP_Token_NAMESPACE:
                    if ('{' === $token->getName()) {
                        $namespace = false;
                        $code .= $token;
                    } else {
                        $namespace = $token->getName();
                        $stream->seek($token->getEndTokenId());
                    }
                    break;

                case $token instanceof \PHP_Token_DECLARE:
                    $buffer = (string) $token;
                    break;

                default:
                    $code .= $token;
            }
        }

        return [$code, $namespace];
    }
Parses a file and returns the code and namespace.

@return string[]