如何在behat+mink中访问onClick属性？

Scenario: Click on element with onClick attribute
    Given I am on the homepage
    When I click on element with onClick attribute
    Then I should see the expected result

use Behat\Behat\Context\Context;
use Behat\Behat\Hook\Scope\BeforeScenarioScope;
use Behat\MinkExtension\Context\MinkContext;

class FeatureContext implements Context
{
    private $minkContext;

    public function __construct()
    {
        $this->minkContext = new MinkContext();
    }

    /**
     * @BeforeScenario
     */
    public function gatherContexts(BeforeScenarioScope $scope)
    {
        $environment = $scope->getEnvironment();
        $environment->registerContextClass(get_class($this->minkContext));
    }

    /**
     * @When /^I click on element with onClick attribute$/
     */
    public function iClickOnElementWithOnClickAttribute()
    {
        $page = $this->minkContext->getSession()->getPage();
        $element = $page->find('css', '[onclick]');
        if ($element) {
            $element->click();
        } else {
            throw new \Exception('Element with onClick attribute not found');
        }
    }
}