public function testEnvCols()
{
$collection = TestUtil::createCollection([['env' => ['uname' => ['os' => 'linux', 'type' => 'penguin']]]]);
$report = $this->generate($collection, ['cols' => ['uname_type', 'uname_os']]);
$this->assertXPathCount($report, 1, '//cell[@name="uname_type" = "penguin"]');
$this->assertXPathCount($report, 1, '//cell[@name="uname_os" = "linux"]');
}