minor symfony#17024 prefer phpunit 5.x on hhvm (eventhorizonpl)

This PR was submitted for the 3.0 branch but it was merged into the 2.3 branch instead (closes symfony#17024).

Discussion
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prefer phpunit 5.x on hhvm

Hi,

HHVM is identified as PHP 5.6 compiler. There are some unsolved problems with tests on hhvm, but using a recent phpunit should be a good start point. How about using 5.1?

Best regards,
Michal

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| License       | MIT

Commits
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7a06d92 prefer phpunit 5.x on hhvm

Author: nicolas-grekas

phpunit

@@ -18,8 +18,8 @@ use Symfony\Component\Process\ProcessUtils;
 error_reporting(-1);
 require __DIR__.'/src/Symfony/Component/Process/ProcessUtils.php';
 
-// PHPUnit 4.8 does not support PHP 7, while 5.0 requires PHP 5.6+
-$PHPUNIT_VERSION = PHP_VERSION_ID >= 70000 ? '5.0' : '4.8';
+// PHPUnit 4.8 does not support PHP 7, while 5.1 requires PHP 5.6+
+$PHPUNIT_VERSION = PHP_VERSION_ID >= 50600 ? '5.1' : '4.8';
 $PHPUNIT_DIR = __DIR__.'/.phpunit';
 $PHP = defined('PHP_BINARY') ? PHP_BINARY : 'php';
 $PHP = ProcessUtils::escapeArgument($PHP);