DumbMathTest.java

import static org.junit.Assert.*;

import org.junit.Test;


public class DumbMathTest {

	@Test
	public void testAddPositiveAndNegative() {
		int a = 12;
		int b = -3;
		int expected = 9;
		int actual = DumbMath.add(a, b);
		assertEquals(expected, actual);
	}
	
	@Test
	public void testAddNegativeAndNegative() {
		int a = -8;
		int b = -3;
		int expected = 9;
		int actual = DumbMath.add(a, b);
		assertEquals(expected, actual);
	}
	
	@Test(expected = ArithmeticException.class)
	public void overflow() {
		int a = Integer.MAX_VALUE;
		int b = Integer.MAX_VALUE;
		DumbMath.add(a, b);
	}

	@Test
	public void testAddFractionNumeratorZero() {
		int n1 = 0;
		int d1 = 5;
		int n2 = 3;
		int d2 = 4;
		double expected = 0.75;
		double actual = DumbMath.addFraction(n1, d1, n2, d2);
		assertEquals(expected, actual, 0);
	}
	
	@Test
	public void testAddFractionHalfPlusThird() {
		int n1 = 1;
		int d1 = 2;
		int n2 = 1;
		int d2 = 3;
		double expected = 5.0/6;
		double actual = DumbMath.addFraction(n1, d1, n2, d2);
		assertEquals(expected, actual, 0.00000000001);
	}
	

}