@Test
public void testWithOnlyOneDP() {

    Transform propagateTransform = new PropagateTransform();
    Map<Long, Double> datapoints = new HashMap<Long, Double>();
    datapoints.put(200000L, 1.0);
    Metric metric = new Metric(TEST_SCOPE, TEST_METRIC);
    metric.setDatapoints(datapoints);
    List<Metric> metrics = new ArrayList<Metric>();
    metrics.add(metric);
    List<String> constants = new ArrayList<String>();
    constants.add("100s");
    Map<Long, Double> expected = new HashMap<Long, Double>();
    expected.put(200000L, 1.0);
    expected.put(300000L, 1.0);
    expected.put(400000L, 1.0);
    expected.put(500000L, 1.0);
    expected.put(600000L, 1.0);
    QueryContext queryContext = new QueryContext();
    TSDBQueryExpression expression = new TSDBQueryExpression();
    expression.setStartTimestamp(200000L);
    expression.setEndTimestamp(600000L);
    queryContext.setExpression(expression);
    List<Metric> result = propagateTransform.transform(queryContext, metrics, constants);
    assertEquals(result.get(0).getDatapoints().size(), 5);
    assertEquals(expected, result.get(0).getDatapoints());
}