Set of test cases for integer division.

testcases.java

@Test
public void division(){
// Positive
Calculator c = new Calculator(4, 2);
assertEquals("Basic division", c.division(), 2);

c = new Calculator(8, 3);
assertEquals("Division with decimals", c.division(), 2);

c = new Calculator(50000000, 10000000);
assertEquals("Basic division with large numbers", c.division(), 5);

c = new Calculator(40, 50);
assertEquals("Division with a less than 1 answer", c.division(), 0);

c = new Calculator(34, 0);
assertEquals("Division by 0", c.division(), 0);

c = new Calculator(655, 1);
assertEquals("Division by 1", c.division(), 655);

// Negative
c = new Calculator(-4, 2);
assertEquals("Basic division", c.division(), -2);

c = new Calculator(8, -3);
assertEquals("Division with decimals", c.division(), -2);

c = new Calculator(-50000000, -10000000);
assertEquals("Basic division with large numbers", c.division(), 5);

c = new Calculator(-40, 50);
assertEquals("Division with a less than 1 answer", c.division(), 0);

c = new Calculator(-34, 0);
assertEquals("Division by 0", c.division(), 0);

c = new Calculator(655, -1);
assertEquals("Division by 1", c.division(), -655);

// Large numbers
c = new Calculator(Integer.MAX_VALUE, Integer.MIN_VALUE + 1);
assertEquals("Divide largest possible number by smallest", c.division(), -1);
}