public void AutoTestCase_Balance_TestAbs()
{
Amount a1 = new Amount("0.00");
Amount a2 = new Amount("$ 123");
Amount a3 = new Amount("EUR 456");
Balance b0 = new Balance();
Balance b1 = new Balance();
Balance b2 = new Balance();
b1 += a1;
b1 += a2;
b1 += a3;
b2 += -a1;
b2 += -a2;
b2 += -a3;
Assert.Equal(b0.Abs(), b0);
Assert.Equal(b2.Abs(), b1.Abs());
Assert.True(b0.Valid());
Assert.True(b1.Valid());
Assert.True(b2.Valid());
}
