public function testHasVersion()
 {
     $p = new Package('foo');
     $p->createVersion('1', 'asdf');
     $this->assertTrue($p->hasVersion('1'));
     $this->assertTrue($p->hasVersion('1', 'asdf'));
     $this->assertTrue($p->hasVersion('1', 'asdf', 'foo'));
     $this->assertFalse($p->hasVersion('2'));
     $this->assertFalse($p->hasVersion('1', 'foo'));
     $p->createVersion('2', 'asdf', 'foo');
     $this->assertTrue($p->hasVersion('2', 'asdf'));
     $this->assertTrue($p->hasVersion('2', 'asdf', 'foo'));
     $this->assertFalse($p->hasVersion('2', 'asdf', 'bar'));
 }