check shop discount

ShopTests.java

package junittests;

import static org.junit.Assert.*;

import lesson6_9.adapter.mvc.shop.*;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.JUnit4;

@RunWith(JUnit4.class)
public class ShopTests {

    private Purchase purchase;
    private Bird bird1;

    @Before
    public void setUp() {
        purchase = new Purchase();
        bird1 = new Eagle();
        bird1.setPrice(100);
        purchase.setBird(bird1);
    }

    @Test
    public void checkDiscount5Percent() {

        double newPrice = bird1.getPrice() * 0.95;
        purchase.setDiscount(5);
        assertTrue(newPrice == purchase.getBird().getPrice());
    }

    @Test
    public void checkDiscount10Percent() {

        double newPrice = bird1.getPrice() * 0.90;
        purchase.setDiscount(10);
        assertTrue(newPrice == purchase.getBird().getPrice());
    }
}