public void TestEnumerator()
{
ImmutableTreeQueue <int> queue = ImmutableTreeQueue <int> .Empty;
ImmutableTreeQueue <int> .Enumerator enumerator = queue.GetEnumerator();
Assert.Equal(0, enumerator.Current);
Assert.False(enumerator.MoveNext());
Assert.Equal(0, enumerator.Current);
Assert.False(enumerator.MoveNext());
Assert.Equal(0, enumerator.Current);
// Adding an item to the queue does not invalidate an enumerator
CollectionAssert.EnumeratorNotInvalidated(queue, () => queue.Enqueue(1));
queue = queue.Enqueue(1);
enumerator = queue.GetEnumerator();
Assert.Equal(0, enumerator.Current);
Assert.True(enumerator.MoveNext());
Assert.Equal(1, enumerator.Current);
// Reset has no effect due to boxing the value type
((IEnumerator <int>)enumerator).Reset();
Assert.Equal(1, enumerator.Current);
Assert.False(enumerator.MoveNext());
Assert.Equal(1, enumerator.Current);
}
public void TestClear()
{
ImmutableTreeQueue <int> queue = ImmutableTreeQueue <int> .Empty;
Assert.Same(queue, queue.Clear());
foreach (int item in Enumerable.Range(0, 10))
{
queue = queue.Enqueue(item);
}
Assert.NotEmpty(queue);
Assert.Same(ImmutableTreeQueue <int> .Empty, queue.Clear());
// Test through the IImmutableQueue<T> interface
IImmutableQueue <int> immutableQueue = queue;
Assert.NotEmpty(immutableQueue);
Assert.Same(ImmutableTreeQueue <int> .Empty, immutableQueue.Clear());
}