Code Coverage - Arrow functions + PHP 7.4.0alpha2 throws a Fatal error: Uncaught Error: Class 'PHP_Token_FN' not found

[xthiago]

Q	A
PHPUnit version	8.2.5
PHP version	PHP 7.4.0alpha2 (cli) (built: Jul 12 2019 01:56:19) ( NTS )
Xdebug version	2.8.0alpha1
Installation Method	Composer

I'm testing PHP 7.4.0alpha2 that comes with the ability to create arrow functions.

I got a fatal error when trying to generate a code coverage report with a codebase that uses arrows function like that:

$getPrice = fn(int $total, InventoryItem $item) => $total + $item->price();

The fatal error:

$ phpunit --coverage-text
PHPUnit 8.2.5 by Sebastian Bergmann and contributors.

Fatal error: Uncaught Error: Class 'PHP_Token_FN' not found in /var/www/app/vendor/phpunit/php-token-stream/src/Token/Stream.php on line 182

Error: Class 'PHP_Token_FN' not found in /var/www/app/vendor/phpunit/php-token-stream/src/Token/Stream.php on line 182

Call Stack:
    0.0076     396696   1. {main}() /var/www/app/vendor/phpunit/phpunit/phpunit:0
    0.0874    1167520   2. PHPUnit\TextUI\Command::main() /var/www/app/vendor/phpunit/phpunit/phpunit:61
    0.0875    1167632   3. PHPUnit\TextUI\Command->run() /var/www/app/vendor/phpunit/phpunit/src/TextUI/Command.php:160
    0.3718    3777800   4. PHPUnit\TextUI\TestRunner->doRun() /var/www/app/vendor/phpunit/phpunit/src/TextUI/Command.php:201
    0.5352    4508032   5. PHPUnit\Framework\TestSuite->run() /var/www/app/vendor/phpunit/phpunit/src/TextUI/TestRunner.php:619
    0.5477    4508224   6. PHPUnit\Framework\TestSuite->run() /var/www/app/vendor/phpunit/phpunit/src/Framework/TestSuite.php:568
    0.5617    4509688   7. PHPUnit\Framework\DataProviderTestSuite->run() /var/www/app/vendor/phpunit/phpunit/src/Framework/TestSuite.php:568
    0.5624    4509880   8. Xthiago\FooTest->run() /var/www/app/vendor/phpunit/phpunit/src/Framework/TestSuite.php:568
    0.5626    4509880   9. PHPUnit\Framework\TestResult->run() /var/www/app/vendor/phpunit/phpunit/src/Framework/TestCase.php:677
    0.6384    4716408  10. SebastianBergmann\CodeCoverage\CodeCoverage->stop() /var/www/app/vendor/phpunit/phpunit/src/Framework/TestResult.php:795
    0.9747    5306424  11. SebastianBergmann\CodeCoverage\CodeCoverage->append() /var/www/app/vendor/phpunit/php-code-coverage/src/CodeCoverage.php:268
    0.9765    5314704  12. SebastianBergmann\CodeCoverage\CodeCoverage->applyIgnoredLinesFilter() /var/www/app/vendor/phpunit/php-code-coverage/src/CodeCoverage.php:299
    1.0183    5677792  13. SebastianBergmann\CodeCoverage\CodeCoverage->getLinesToBeIgnored() /var/www/app/vendor/phpunit/php-code-coverage/src/CodeCoverage.php:556
    1.0183    5677792  14. SebastianBergmann\CodeCoverage\CodeCoverage->getLinesToBeIgnoredInner() /var/www/app/vendor/phpunit/php-code-coverage/src/CodeCoverage.php:615
    1.0241    5700960  15. PHP_Token_Stream->__construct() /var/www/app/vendor/phpunit/php-code-coverage/src/CodeCoverage.php:638
    1.0269    5709152  16. PHP_Token_Stream->scan() /var/www/app/vendor/phpunit/php-token-stream/src/Token/Stream.php:112

The code coverage report generation works fine after refactoring the arrows functions to old-style anonymous functions:

$getPrice = function (int $total, InventoryItem $item) { return $total + $item->price(); };

I'm not sure it must be reported here or in sebastianbergmann/php-token-stream.

[sebastianbergmann]

Should be taken care of by e899757.

[xthiago]

Yes, it works. Thank you!

[NicklasWallgren]

@sebastianbergmann We have encountered this issue with PHP 7.4, on phpunit/phpunit ^6.1

It might be a good idea to port this to earlier versions of the library, for example the 2.0 branch. Would you accept a PR?

[sebastianbergmann]

PHPUnit 6 is not supported on PHP 7.4: https://phpunit.de/supported-versions.html

[NicklasWallgren]

Okey, thanks for the clarification.