BeveragesPricingTest.java

package unit_tests;

import beverages.*;
import beverages.supplements.WithCinnamon;
import beverages.supplements.WithCream;
import beverages.supplements.WithMilk;
import org.junit.Assert;
import org.junit.Test;

import static org.hamcrest.CoreMatchers.is;
import static org.hamcrest.MatcherAssert.assertThat;
import static org.hamcrest.Matchers.closeTo;

public class BeveragesPricingTest {
  private static final double PRECISION = 0.001;

  @Test
  public void computes_coffee_price() {
    Beverage coffee = new Coffee();
    assertThat(coffee.price(), is(closeTo(1.20, PRECISION)));
  }

  @Test
  public void computes_tea_price() {
    Beverage tea = new Tea();
    assertThat(tea.price(), is(closeTo(1.50, PRECISION)));
  }

  @Test
  public void computes_hot_chocolate_price() {
    Beverage hotChocolate = new HotChocolate();
    assertThat(hotChocolate.price(), is(closeTo(1.45, PRECISION)));
  }

  @Test
  public void computes_tea_with_milk_price() {
    Beverage teaWithMilk = new WithMilk(new Tea());
    assertThat(teaWithMilk.price(), is(closeTo(1.60, PRECISION)));
  }

  @Test
  public void computes_coffee_with_milk_price() {
    Beverage coffeWithMilk = new WithMilk(new Coffee());
    assertThat(coffeWithMilk.price(), is(closeTo(1.30, PRECISION)));
  }

  @Test
  public void computes_coffee_with_milk_and_cream_price() {
    Beverage coffeeWithMilkAndCream = new WithMilk(new WithCream(new Coffee()));
    assertThat(coffeeWithMilkAndCream.price(), is(closeTo(1.45, PRECISION)));
  }

  @Test
  public void computes_hot_chocolate_with_cream_price() {
    Beverage hotChocolateWithCream = new WithCream(new HotChocolate());
    assertThat(hotChocolateWithCream.price(),  is(closeTo(1.60, PRECISION)));
  }

  @Test
  public void computes_coffee_with_cinnamon_price() {
    Beverage coffeeWithCinamon = new WithCinnamon(new Coffee());
    Assert.assertThat(coffeeWithCinamon.price(), is(closeTo(1.25, PRECISION)));
  }
}