@Test
        @FeatureRequirement(featureClass = Graph.Features.VariableFeatures.class, feature = FEATURE_VARIABLES, supported = false)
        public void shouldSupportMemoryIfAGraphAcceptsMemory() throws Exception {
            try {
                graph.variables();
                fail(String.format(INVALID_FEATURE_SPECIFICATION, Graph.Features.VariableFeatures.class.getSimpleName(), FEATURE_VARIABLES));
            } catch (Exception e) {
                validateException(Graph.Exceptions.variablesNotSupported(), e);
            }
        }
A {@link Graph} that does not support {@link Graph.Features.VariableFeatures#FEATURE_VARIABLES} must call
{@link Graph.Exceptions#variablesNotSupported()}.
gremlin-test/src/main/java/org/apache/tinkerpop/gremlin/structure/FeatureSupportTest.java