@Test
    void testTraceOneSourceWithCloning() {
        Chain<Searcher> mainChain = twoTracingSources();

        Query q = new Query(com.yahoo.search.test.QueryTestCase.httpEncode("?query=test&traceLevel=1&sources=source1"));

        Execution execution = new Execution(mainChain, Execution.Context.createContextStub(chainRegistry));
        Result result = execution.search(q);
        assertNull(result.hits().getError());
        TwoSourceChecker lookForTraces = new TwoSourceChecker();
        execution.trace().accept(lookForTraces);
        assertTrue(lookForTraces.traceFromSource1);
        assertFalse(lookForTraces.traceFromSource2);

    }
Test for federation searcher. The searcher is also tested in
com.yahoo.prelude.searcher.test.BlendingSearcherTestCase.

@author Arne Bergene Fossaa
container-search/src/test/java/com/yahoo/search/federation/FederationSearcherTestCase.java