@Test
public void execute() {

    RegistryContext registryContext = new ContextImpl();
    GetDMNDecisionResultsCommand getDMNDecisionResultsCommand = new GetDMNDecisionResultsCommand();
    assertThatThrownBy(() -> getDMNDecisionResultsCommand.execute(registryContext))
            .isInstanceOf(IllegalStateException.class)
            .hasMessage("There is no DMNResult available");
    DMNResultImpl dmnResult = new DMNResultImpl(null);
    dmnResult.setContext(new DMNContextImpl());
    registryContext.register(DMNResult.class, dmnResult);
    List<DMNDecisionResult> result = getDMNDecisionResultsCommand.execute(registryContext);
    assertEquals(0, result.size());
}