public void TestDivideByZero()
{
var c = new MockCalculator(_resultWriter);
var result = c.Divide(6, 0);
Assert.Equal(result, double.NaN);
}
public void TestDivide()
{
var c = new MockCalculator(_resultWriter);
var result = c.Divide(6, 3);
Assert.Equal(result, 2);
}