@Test
        @FeatureRequirement(featureClass = Graph.Features.VariableFeatures.class, feature = Graph.Features.VariableFeatures.FEATURE_VARIABLES)
        @FeatureRequirement(featureClass = Graph.Features.VariableFeatures.class, feature = Graph.Features.VariableFeatures.FEATURE_STRING_VALUES)
        public void testVariables() {
            final Graph.Variables variables = graph.variables();
            variables.set("xo", "test1");
            variables.set("yo", "test2");
            variables.set("zo", "test3");

            tryCommit(graph, graph -> assertEquals(StringFactory.graphVariablesString(variables), variables.toString()));
        }
Basic tests to ensure that {@link Graph.Variables} have appropriate {@link String} representations.
gremlin-test/src/main/java/org/apache/tinkerpop/gremlin/structure/VariablesTest.java