Carew\Document::setVar PHP Method

    public function setVar($key, $value)
    {
        $this->vars[$key] = $value;
        return $this;
    }

 public function testGetSetVar()
 {
     $document = new Document();
     $this->assertSame(null, $document->getVar('foo'));
     $this->assertSame('default', $document->getVar('foo', 'default'));
     $document->setVar('foo', 'bar');
     $this->assertSame('bar', $document->getVar('foo'));
     $this->assertSame('bar', $document->getVar('foo', 'default'));
 }