@Test
    public void shouldGetStepsOfAssignableClassRecursivelyFromDepthOneType() {
        final Traversal.Admin<?,?> traversal = __.V().repeat(__.out()).project("x").by(out().in().fold()).asAdmin();
        final List<Step<?,?>> steps = TraversalHelper.getStepsOfAssignableClassRecursivelyFromDepth(traversal, VertexStep.class);
        assertEquals(3, steps.size());
        assertThat(steps.stream().allMatch(s -> s instanceof VertexStep), is(true));
    }
@author Marko A. Rodriguez (http://markorodriguez.com)
@author Stephen Mallette (http://stephen.genoprime.com)
gremlin-core/src/test/java/org/apache/tinkerpop/gremlin/process/traversal/util/TraversalHelperTest.java