public void Item_Cached_After_Initial_Retrieval()
{
    var peteDataProviderMock = new Mock<IPeteDataProvider>();
        var testId = Guid.NewGuid().ToString();
        peteDataProviderMock.Setup(x => x.ObjectContext.GetHierarchy()).Returns(new[] { new GetHierarchy_Result { Id = testId }});

        var dataProvider = new TaxonomyDataProvider(peteDataProviderMock.Object);

        for (var i = 1; i <= 10; i++)
            Assert.That(dataProvider.GetNode(testId).Id, Is.EqualTo(testId));

        peteDataProviderMock.Verify(x => x.ObjectContext.GetHierarchy(), Times.Once());
}