public void CanDeleteCurrentEntry()
{
var engine = new Engine();
engine.Digit(1);
Assert.AreEqual(1, engine.Value);
engine.ClearEntry();
Assert.AreEqual(0, engine.Value);
}
public void CanDeleteCurrentEntryWhenOperatorIsOnStack()
{
var engine = new Engine();
engine.Digit(1);
Assert.AreEqual(1, engine.Value);
engine.Plus();
Assert.AreEqual(1, engine.Value);
engine.ClearEntry();
Assert.AreEqual(0, engine.Value);
engine.Digit(2);
Assert.AreEqual(2, engine.Value);
engine.Equals();
Assert.AreEqual(3, engine.Value);
}