    @Test
    public void shouldCallArasContext() throws QueryScriptException {

        final String query = "'x'='y'";
        final String walkPredicate = "rdf:type";

        ScriptEngineContext ctx = mock(ScriptEngineContext.class);
        NodeSet nodeSet = mock(NodeSet.class);

        when(ctx.query(anyString())).thenReturn(nodeSet);
        when(nodeSet.walk(anyString())).thenReturn(nodeSet);

        QueryScriptEngine engine = new QueryScriptEngine(ctx);
        engine.execute(
                "query(\"" +  query + "\")" +
                "   .walk('" + walkPredicate + "')" +
                        ".result();");

        verify(ctx).query(Mockito.eq(query));
        verify(nodeSet).walk(Mockito.eq(walkPredicate));
        verify(nodeSet).result();
    }