Codeception 'Undefined variable output' when trying to run a unit test - php

Question

When attempting to run a simple unit test, as follows
// tests
public function testMe()
{
$this->assertEquals(1+1, 2);
}
I get the following error:
PHP Notice: Undefined variable: output in phar://C:/bin/codecept.phar/src/Codeception/Lib/Parser.php on line 129
PHP Stack trace:
PHP 1. {main}() C:\bin\codecept.phar:0
PHP 2. require_once() C:\bin\codecept.phar:7
PHP 3. Codeception\Application->run() phar://C:/bin/codecept.phar/codecept:36
PHP 4. Symfony\Component\Console\Application->run() phar://C:/bin/codecept.phar/src/Codeception/Application.php:103
PHP 5. Symfony\Component\Console\Application->doRun() phar://C:/bin/codecept.phar/vendor/symfony/console/Application.php:117
PHP 6. Symfony\Component\Console\Application->doRunCommand() phar://C:/bin/codecept.phar/vendor/symfony/console/Application.php:186
PHP 7. Symfony\Component\Console\Command\Command->run() phar://C:/bin/codecept.phar/vendor/symfony/console/Application.php:815
PHP 8. Codeception\Command\Run->execute() phar://C:/bin/codecept.phar/vendor/symfony/console/Command/Command.php:256
PHP 9. Codeception\Command\Run->runSuites() phar://C:/bin/codecept.phar/src/Codeception/Command/Run.php:256
PHP 10. Codeception\Codecept->run() phar://C:/bin/codecept.phar/src/Codeception/Command/Run.php:329
The line in question, 129 in Parser.phpis the following:
public static function validate($file)
{
$config = Configuration::config();
if (empty($config['settings']['lint'])) { // lint disabled in config
return;
}
exec("php -l ".escapeshellarg($file)." 2>&1", $output, $code);
if ($code !== 0) {
throw new TestParseException($file, implode("\n", $output));
}
}
The line 129 is exec("php -l ".escapeshellarg($file)." 2>&1", $output, $code);
I have tried googling around, and couldn't find any one else with the issue. This is in a completely "empty" php project, with only this unit test. I installed Codeception with composer.
I created the test as follows:
codecept generate:test unit Example
filled in the above and
codecept run unit
Codeception version: 2.2.2
Php version: 5.6.21

Answer 1

Ok I found more information, namely here:
https://github.com/Codeception/Codeception/issues/3324
It seems that this is a very new problem with version "2.2.*"
The possible solutions are:
Disable linting
Insert
settings:
lint: false
Into the codeception.yaml file.
Downgrade
Since validation is introduced in version 2.2, downgrading to the latest version (2.1.11) should also fix the issue according to the devs.