@Test
    void testProcessingHandlerPropagatesRequestParametersAndContext() {
        List<Chain<Processor>> chains = new ArrayList<>();
        chains.add(new Chain<>("default", new RequestPropertyTracer()));
        driver = new ProcessingTestDriver(chains);
        assertTrue(driver.sendRequest("http://localhost/?chain=default&tracelevel=4").readAll().contains("context.contextVariable: '37'"),
                "JDisc request context is propagated to properties()");
    }
Tests processing handler scenarios end to end.

@author bratseth
@author gjoranv
@author Tony Vaagenes
container-core/src/test/java/com/yahoo/processing/handler/ProcessingHandlerTestCase.java