Horde_Imap_Client_Data_Capability::query PHP Method

    public function query($capability, $parameter = null)
    {
        $capability = Horde_String::upper($capability);
        if (!isset($this->_data[$capability])) {
            return false;
        }
        return is_null($parameter) ?: is_array($this->_data[$capability]) && in_array(Horde_String::upper($parameter), $this->_data[$capability]);
    }

 public function testRemoval()
 {
     $c = new Horde_Imap_Client_Data_Capability();
     $c->add('FOO');
     $this->assertTrue($c->query('FOO'));
     $c->remove('FOO');
     $this->assertFalse($c->query('FOO'));
     $c->add('BAR', array('A', 'B', 'C'));
     $c->remove('BAR', array('A', 'C'));
     $this->assertTrue($c->query('BAR'));
     $this->assertFalse($c->query('BAR', 'A'));
     $this->assertTrue($c->query('BAR', 'B'));
     $this->assertFalse($c->query('BAR', 'C'));
     $c->remove('BAR', 'b');
     $this->assertFalse($c->query('BAR'));
     $this->assertFalse($c->query('BAR', 'A'));
     $this->assertFalse($c->query('BAR', 'B'));
     $this->assertFalse($c->query('BAR', 'C'));
 }