public void TestPush()
{
var sut = new SungStack <int>();
sut.Push(1);
sut.Push(2);
sut.Push(3);
int[] expected = { 3, 2, 1 };
Assert.True(expected.SequenceEqual(sut.Traverse().ToArray()));
}
public void TestPeek()
{
var sut = new SungStack <int>();
const int itemCount = 3;
for (int i = 1; i <= itemCount; i++)
{
sut.Push(i);
Assert.Equal(i, sut.Peek());
}
for (int i = itemCount - 1; i >= 0; i--)
{
sut.Pop();
Assert.Equal(i, sut.Peek());
}
// default(int) returns 0
Assert.Equal(0, sut.Peek());
}
public void TestPop()
{
var sut = new SungStack <int>();
sut.Push(1);
sut.Push(2);
sut.Push(3);
var popped = sut.Pop();
Assert.Equal(3, popped);
Assert.True(new[] { 2, 1 }.SequenceEqual(sut.Traverse().ToArray()));
popped = sut.Pop();
Assert.Equal(2, popped);
Assert.True(new[] { 1 }.SequenceEqual(sut.Traverse().ToArray()));
popped = sut.Pop();
Assert.Equal(1, popped);
Assert.True(new int[] {}.SequenceEqual(sut.Traverse().ToArray()));
Assert.Throws <InvalidOperationException>(() => sut.Pop());
}
