package com.changenode;
   
   import org.junit.jupiter.api.Test;
   import org.slf4j.Logger;
   import org.slf4j.LoggerFactory;
   
   import static org.assertj.core.api.Assertions.assertThat;
   
   public class CalculatorTest {
  
      private Calculator calculator = new Calculator();
  
      private static final Logger LOG = LoggerFactory.getLogger(CalculatorTest.class);
  
      // TODO Add some more javadoc here!
      @Test
      public void testAdd() {
          assertThat(calculator.value()).isZero();
          calculator.add(5);
          assertThat(calculator.value()).isEqualTo(5);
      }
  
      @Test
      public void testSubtract() {
          assertThat(calculator.value()).isZero();
          calculator.subtract(5);
          assertThat(calculator.value()).isEqualTo(-5);
  
      }
  
      @Test
      public void testMultiply() {
          assertThat(calculator.value()).isZero();
  
          calculator.add(5).multiply(2);
  
          assertThat(calculator.value()).isEqualTo(10);
  
      }
  
      @Test
      public void testDivide() {
          assertThat(calculator.value()).isZero();
  
          calculator.add(10).divide(2);
  
          assertThat(calculator.value()).isEqualTo(5);
  
      }
  
      /**
       * @see <a href=
       * "http://stackoverflow.com/questions/14137989/java-division-by-zero-doesnt-throw-an-arithmeticexception-why"
       * >Why doesn't divide by zero return an error?</a>
       */
      @Test()
      public void testDivideByZero() {
          calculator.divide(2);
          LOG.info("Divide by zero results in... {}", calculator.value());
          assertThat(calculator.value()).isEqualTo(0);
      }
  
      @Test
      public void testAbitrary() {
          assertThat(calculator.arbitrarilyComplexMethod("bar", 0, null, null, null)).isEqualTo(0);
  
          assertThat(calculator.arbitrarilyComplexMethodPart2("bar", 0, null, null, null)).isEqualTo(0);
      }
  
  }