placer.stepStarted(stepScopeA3);
assertAllCodesOfIterator(placementIterator.next().iterator(),
"a1", "a2", "b1");
placer.stepEnded(stepScopeA3);
placer.phaseEnded(phaseScopeA);
AbstractPhaseScope phaseScopeB = mock(AbstractPhaseScope.class);
when(phaseScopeB.getSolverScope()).thenReturn(solverScope);
placer.phaseStarted(phaseScopeB);
placementIterator = placer.iterator();