与symfony2.8的behat情节篮子

Question

我知道在symfony 2中，现在我有测试简单的场景 我有这个实体：

<?php

namespace test\MedBundle\Entity;

use test\MedBundle\Entity\Product;
/**
 * Basket
 */
class Basket
{
    /**
     * @var int
     */
    private $id;


    /**
     * Get id
     *
     * @return int
     */
    public function getId()
    {
        return $this->id;
    }

     /**
     * @ORM\OneToMany(targetEntity="test\MedBundle\Entity\Product",mappedBy="basket")
    */
    private $products;


     public function __construct()
    {
        $this->products = new \Doctrine\Common\Collections\ArrayCollection();
    }

    /**
     * Add products
     *
     * @param \test\MedBundle\Entity\Product $products
     *
     * @return Basket
     */
    public function addProducts(\test\MedBundle\Entity\Product $products)
    {
        $this->products[] = $products;

        return $this;
    }

    /**
     * Remove products
     *
     * @param \test\MedBundle\Entity\Product $products
     */
    public function removeProducts(\test\MedBundle\Entity\Product $products)
    {
        $this->products->removeElement($products);
    }

    /**
     * Get products
     *
     * @return \Doctrine\Common\Collections\Collection
     */
    public function getProducts()
    {
        return $this->products;
    }

    public function price(){
        $price =0;
        foreach($this->products as $product){
            $price = $product->getPrice();
        }
    }


}

和此实体产品：

<?php

namespace test\MedBundle\Entity;

/**
 * Product
 */
class Product
{
    /**
     * @var int
     */
    private $id;

    /**
     * @var string
     */
    private $price;

        /**
     * @ORM\ManyToOne(targetEntity="basket",inversedBy="products")
     * @ORM\JoinColumn(name="id_basket", referencedColumnName="id",nullable=true)
     */
  private $basket;

    /**
     * Get id
     *
     * @return int
     */
    public function getId()
    {
        return $this->id;
    }


    /**
     * Set price
     *
     * @param string $price
     *
     * @return Product
     */
    public function setPrice($price)
    {
        $this->price = $price;

        return $this;
    }

    /**
     * Get price
     *
     * @return string
     */
    public function getPrice()
    {
        return $this->price;
    }
}

现在我有这种情况：

Feature: Basket

    Permet de vérifier que le panier fonctionne


  Scenario: Multiple products are added to the basket
    Given An empty basket

    When A product costing 5 $ is added to the basket

    And A product costing 15 $ is added to the basket

    Then the basket price is 20 €  

这是我的FeatureContext.php：

<?php

namespace test\MedBundle\Behat\Context;

use Behat\Behat\Context\Context;
use Behat\Gherkin\Node\PyStringNode;
use Behat\Gherkin\Node\TableNode;
use Behat\Behat\Context\BehatContext;
use Behat\Behat\Exception\PendingException;
use test\MedBundle\Entity\Basket;
use test\MedBundle\Entity\Product;

/**
 * Defines application features from the specific context.
 */
class FeatureContext implements Context
{
    /**
     * Initializes context.
     *
     * Every scenario gets its own context instance.
     * You can also pass arbitrary arguments to the
     * context constructor through behat.yml.
     */
    public function __construct()
    {
    }

    /**
     * @Given an empty basket
     */
    public function anEmptyBasket()
    {
        $this->basket = new Basket();
    }


    /**
     * @Given A product costing :price $ is added to basket
     */
    public function aProductCostingIsAddedToBasket($price)
    {
        $product = new Product($price);
        $this->basket->addProducts($product);

    }

    /**
     * @Then the basket price is :price €
     */
    public function theBasketPriceIsEu($price)
    {
        if ($this->basket->price() != $price) {
            throw new Exception('le prix ne correspend pas');
        }
    }


}

但是当我测试我的场景时，我有这个问题

enter image description here

请帮助我，谢谢你