public async Task IsInitializedAsync_ShouldReturnFalse_IfNoDocument()
        {
            var client = Mock.Of <IChangeFeedDocumentClient>();

            Mock.Get(client)
            .Setup(c => c.ReadDocumentAsync(It.Is <Uri>(uri => uri.ToString().EndsWith(storeMarker))))
            .ThrowsAsync(DocumentExceptionHelpers.CreateNotFoundException());

            var  leaseStore = new LeaseStore(client, collectionInfo, containerNamePrefix, leaseStoreCollectionLink);
            bool isInited   = await leaseStore.IsInitializedAsync();

            Assert.False(isInited);
        }
        public async Task IsInitializedAsync_ShouldReturnTrue_IfDocumentExist()
        {
            var client = Mock.Of <IChangeFeedDocumentClient>();

            Mock.Get(client)
            .Setup(c => c.ReadDocumentAsync(It.Is <Uri>(uri => uri.ToString().EndsWith(storeMarker))))
            .ReturnsAsync(CreateResponse());

            var  leaseStore = new LeaseStore(client, collectionInfo, containerNamePrefix, leaseStoreCollectionLink);
            bool isInited   = await leaseStore.IsInitializedAsync();

            Assert.True(isInited);
        }