public function invalidTagsAreRecognizedAsInvalid()
{
$identifier = 'someCacheIdentifier';
$backend = $this->createMock(AbstractBackend::class);
$cache = $this->getMockBuilder(StringFrontend::class)->setMethods(['__construct', 'get', 'set', 'has', 'remove', 'getByTag'])->setConstructorArgs([$identifier, $backend])->getMock();
foreach (['', 'abc def', 'foo!', 'bar:', 'some/', 'bla*', 'one+', 'äöü', str_repeat('x', 251), 'x$', '\\a', 'b#'] as $tag) {
$this->assertFalse($cache->isValidTag($tag), 'Invalid tag "' . $tag . '" was not rejected.');
}
}