failedOutcomeValue ignored if chained with multiple AndThen statements

[tjaskula]

Seems like this is the bug that you can easily reproduce with the following test:

@Test
  public void TestThatFailureOutcomeFails()
  {
    final Completes<Integer> completes = new BasicCompletes<>(new Scheduler());
    completes
            .andThen(new Integer(-100), (value) -> 2 * value)
            .andThen((x) -> andThenValue = x)
            .otherwise((x) -> failureValue = 1000);

    completes.with(-100);
    Integer completed = completes.await();

    assertTrue(completes.hasFailed());
    assertEquals(new Integer(-1), andThenValue);
    assertEquals(new Integer(1000), failureValue);
  }

The failedOutcomeValue from .andThen(new Integer(-100), (value) -> 2 * value) is not taken into account. When calling completes.with(-100); this line : https://github.com/vlingo/vlingo-common/blob/c858e9235d1912c1afc5fe5a881627955820a7f0/src/main/java/io/vlingo/common/BasicCompletes.java#L565 evaluates to null

As suggested by @VaughnVernon it might be that the second andThen overwrites the value with null because it is not nested but added up to the first andThen

[tjaskula]

@VaughnVernon Checked the test and it still fails and completes.hasFailed() is false

As I'm changing in .NET implementation how continuations are executed, I have exactly the same problem now. From what I see as .andThen(new Integer(-100), (value) -> 2 * value) is scheduled for execution immediately when we call completes.With(-100); it doesn't matter anymore, because the continuation was already run.

I'm lost what should be the correct behavior.

[tjaskula]

@VaughnVernon Checked the test and it still fails and completes.hasFailed() is false

As I'm changing in .NET implementation how continuations are executed, I have exactly the same problem now. From what I see as .andThen(new Integer(-100), (value) -> 2 * value) is scheduled for execution immediately when we call completes.With(-100); it doesn't matter anymore, because the continuation was already run.

I'm lost what should be the correct behavior.

Seems like it's not that. Everything starts to execute only when with(-100) is called. So it seems that it's not fixed yet

[VaughnVernon]

@tjaskula The execution must not start until with(outcome). The test is clean on local and Travis. There were bugs in your test so I had to change it. See the fixed test in BasicCompletesTest.

[tjaskula]

@VaughnVernon Ok, this is the new test

@Test
  public void testThatNonNullFailureOutcomeFails() {
    final Completes<Integer> completes = new BasicCompletes<>(new Scheduler());

    completes
            .andThen(new Integer(-100), (value) -> 2 * value)
            .andThen((x) -> andThenValue = x)
            .otherwise((x) -> failureValue = 1000);

    completes.with(-100);

    final Integer completed = completes.await();

    assertTrue(completes.hasFailed());
    assertEquals(new Integer(1000), completed);
    assertEquals(null, andThenValue);
    assertEquals(new Integer(1000), failureValue);
  }

My question is why assertEquals(new Integer(1000), completed); ? I thought that in that case the execution of 2 * value should not have happened and the 1000 not computed ?

It means that even if the failedOutcomeValue == passed in value it executes the current continuation but not the next one and if fails back to otherwise ?

[VaughnVernon]

@tjaskula The otherwise is executed because of the failure valve and it sets 1000.

[tjaskula]

Ok, so it executes the function and tries to execute the Otherwise branch with failedOutcome

[VaughnVernon]

Yes. It should be that any outcome in the pipeline that produces the failure value should execute the otherwise function. This includes before the first andThen.

[tjaskula]

Ok but the failure value must equal the outcome of previous execution or passed in value