Prado\Collections\TPriorityMap::remove PHP Method

    public function remove($key, $priority = false)
    {
        if (!$this->_r) {
            if ($priority === null) {
                $priority = $this->getDefaultPriority();
            }
            if ($priority === false) {
                $this->sortPriorities();
                foreach ($this->_d as $priority => $items) {
                    if (array_key_exists($key, $items)) {
                        $value = $this->_d[$priority][$key];
                        unset($this->_d[$priority][$key]);
                        $this->_c--;
                        if (count($this->_d[$priority]) === 0) {
                            unset($this->_d[$priority]);
                            $this->_o = false;
                        }
                        $this->_fd = null;
                        return $value;
                    }
                }
                return null;
            } else {
                $priority = (string) round(TPropertyValue::ensureFloat($priority), $this->_p);
                if (isset($this->_d[$priority]) && (isset($this->_d[$priority][$key]) || array_key_exists($key, $this->_d[$priority]))) {
                    $value = $this->_d[$priority][$key];
                    unset($this->_d[$priority][$key]);
                    $this->_c--;
                    if (count($this->_d[$priority]) === 0) {
                        unset($this->_d[$priority]);
                        $this->_o = false;
                    }
                    $this->_fd = null;
                    return $value;
                } else {
                    return null;
                }
            }
        } else {
            throw new TInvalidOperationException('map_readonly', get_class($this));
        }
    }

 public function testCanNotRemoveWhenReadOnly()
 {
     $map = new TPriorityMap(array('key' => 'value'), true);
     try {
         $map->remove('key');
     } catch (TInvalidOperationException $e) {
         return;
     }
     self::fail('An expected TInvalidOperationException was not raised');
 }