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fix(bus): stop hardware-thread subscribers, primitive subscribe, widened casts - #32
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…ned casts Three defects found by auditing the publish path, each reproduced against the real classes before being fixed. 1. unregisterNode / unsubscribe did not stop an @OnHardwareThread subscriber. markSubscriptionAsHardwareThreaded replaces the list entry with a wrapper, but Subscription.handler() still returns the unwrapped handler, so removeSubscription searched for something the list no longer held and returned silently. An unregistered node kept receiving publishes, so it could still drive hardware. hardwareRerouted already recorded the registered wrapper; it was written but never read. 2. subscribe(String, int.class, handler) registered and then never fired. Class.cast() returns false for every argument when the class is primitive, so every delivery threw ClassCastException and dispatchCallback swallowed it into a log line. The type is boxed before the runtime check, matching the primitive/wrapper equivalence the publish path already applies. 3. getOrCreateTopic / findTopic / getLatestValue handed back a value the caller could not cast to the requested type. Object.isAssignableFrom( String) is true, so an Object topic satisfied a request for String, and the erased cast failed later at the caller's own line -- after isPresent() had already reported a value present. New Topic.safelyReturnsAs refuses the request with a message naming the actual type. Narrowing to a type the topic really holds still works, and subscribeRaw keeps accepting an Object topic because its handler receives Object, which is the binder's supported "several handlers, one topic" configuration. Tests: new SubscriptionLifetimeTest covers all three; each fails when its fix is reverted. Also in TopicLockFreeTest: - The concurrency test counted no samples, so it passed even if latest() returned empty always and every check inside the reader was skipped. It now counts and asserts a non-zero observation count. - Two assertions compared a value with itself: latest().publishNanos() against latestPublishNanos() (both read the same volatile field), and acceptsValueClass against acceptsType (which delegates to it). Replaced with literal expectations and with an externally-clocked publish window, which is the only form that cannot be satisfied by a skewed timestamp. - latestPublishNanos() now has its own window-bracketed assertion, so replacing it with a live clock reading fails the test. Docs: a comment records why the install-ordering guarantee is not covered by a test. The sample-to-store window is nanoseconds wide; a spinning detector catches it 3 runs in 6 but starves publishers and hung the suite, and a yielding detector never catches it. A test that cannot fail reliably is worse than none. CI: the Docker workflow's merge job never prepared IMAGE, so buildx got "@sha256:..." with no repository and the multi-arch manifest step failed. The published image has not updated since at least ce0f407; every build job recomputes IMAGE locally via GITHUB_ENV and that does not cross the job boundary. Suite: 90 tests, 0 failures across 10 consecutive runs and on a 2-core-pinned runner. javadoc: 0 errors, no new warnings.
Reviewer's GuideFixes three publish-path defects: hardware-thread subscribers now stop after removal, primitive subscriptions deliver correctly, and typed topic lookups reject unsafe generic narrowing. The PR also repairs Docker manifest image naming and hardens regression tests against vacuous or self-referential assertions. Sequence diagram for removing a hardware-thread subscriptionsequenceDiagram
participant Caller
participant OrchestratorImpl
participant SubscriberList
participant HardwareThread
Caller->>OrchestratorImpl: unregisterNode(name)
OrchestratorImpl->>OrchestratorImpl: removeSubscription(sub)
OrchestratorImpl->>OrchestratorImpl: hardwareRerouted.getOrDefault(sub, sub.handler())
OrchestratorImpl->>SubscriberList: remove(registered)
SubscriberList-->>OrchestratorImpl: subscription removed
OrchestratorImpl->>OrchestratorImpl: hardwareRerouted.remove(sub)
Caller->>OrchestratorImpl: publish(topic, message)
OrchestratorImpl->>SubscriberList: dispatchCallback(message)
SubscriberList-->>OrchestratorImpl: removed subscriber is not invoked
Sequence diagram for primitive-type subscription deliverysequenceDiagram
participant Caller
participant OrchestratorImpl
participant Topic
participant SubscriberList
participant Handler
Caller->>OrchestratorImpl: subscribe(topicName, int.class, handler)
OrchestratorImpl->>OrchestratorImpl: getOrCreateTopic(topicName, int.class)
OrchestratorImpl->>Topic: box(int.class)
OrchestratorImpl->>SubscriberList: add(wrapped)
Caller->>OrchestratorImpl: publish(topicName, Integer)
OrchestratorImpl->>SubscriberList: dispatchCallback(message)
SubscriberList->>Topic: box(int.class)
SubscriberList->>Handler: accept(Integer)
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Navigate logical layers of code changes, visualize relationships, and explore their blast radius. 📝 WalkthroughWalkthroughThe pull request updates typed topic access checks, primitive subscription delivery, and removal of hardware-threaded subscriptions. It also adjusts topic tests and prepares the Docker image reference within the merge job. ChangesTopic access and subscription fixes
Docker merge workflow
Priority: ➖ Normal Estimated code review effort: 3 (Moderate) | ~20 minutes Change: Bug fix Merge Risk: 🟡 Moderate · up to The hardware-thread unsubscribe fix works in the common path. However, concurrent or repeated rerouting can still leave an unsubscribed callback active. The new tests can fail intermittently or pass without testing removal. Address these before merging. Security Architecture ReviewSecurity architecture risk: 🔵 Low · up to The changes strengthen typed reads and correct normal hardware-threaded subscription removal. No newly introduced security attack path was established. Existing concurrency and queued-callback limitations remain, and deployment-specific hardware authority is not established. Retained concerns Security review detailsSecurity Blast Radius
Trust Boundaries and Controls
Resilience and Maintainability Implications
Hardening Proposals
🚥 Pre-merge checks | ✅ 4 | ❌ 1❌ Failed checks (1 warning)
✅ Passed checks (4 passed)
Full details: Docstring CoverageExplanation Docstring coverage is 42.31% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 26 functions across 4 files. (2 skipped: 2 unsupported.)
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Hey - I've reviewed your changes and they look great!
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Needs a human reviewer. The workflow change alters how the multi-architecture release manifest is published; if the image name is computed incorrectly, a release can fail or publish the wrong artifact, and reverting cannot undo an already-published result. The subscription and typed-lookup changes are otherwise reversible runtime behavior, with defects normally fixed by a subsequent release.
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Actionable comments posted: 3
- 🪄 Fix CodeRabbit comments on this PR
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Inline comments:
Review comments at @src/main/java/com/aaravlabs/synapse/OrchestratorImpl.java:
- Around line 457-459: Serialize `removeSubscription` and
`markSubscriptionAsHardwareThreaded` on the same lock so removal cannot race
with rerouting. In `markSubscriptionAsHardwareThreaded`, record the wrapper in
`hardwareRerouted` only when `SubscriberList.replace` succeeds; update `replace`
to report success so repeated marks cannot overwrite the registered wrapper.
Review comments at
@src/test/java/com/aaravlabs/synapse/SubscriptionLifetimeTest.java:
- Around line 43-44: Update the assertion in SubscriptionLifetimeTest to verify
that both published values arrived without requiring a callback order; retain
the check that neither value was dropped.
- Around line 128-139: Update both hardware callback tests in
SubscriptionLifetimeTest to assert that hits is positive immediately after each
await and before testing removal, so a callback that never runs fails the test
instead of allowing a zero-hit comparison to pass.
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CHANGELOG.md (1)
134-152: LGTM!
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8 issues found across 6 files
Tip: instead of fixing issues one by one fix them all with cubic
Re-trigger cubic
Prompt for AI agents (unresolved issues)
Check if these issues are valid — if so, understand the root cause of each and fix them. When an issue isn't valid or won't be fixed in this PR, reply in its thread with the reason and then resolve the thread. If appropriate, use sub-agents to investigate and fix each issue separately.
<file name="src/main/java/com/aaravlabs/synapse/Topic.java">
<violation number="1" location="src/main/java/com/aaravlabs/synapse/Topic.java:224">
P3: `safelyReturnsAs` is not strictly stronger than `acceptsType`; it checks the opposite assignability direction. Describe it as a complementary or opposite-direction check so the documentation explains why callers must retain both predicates.</violation>
</file>
<file name="src/test/java/com/aaravlabs/synapse/SubscriptionLifetimeTest.java">
<violation number="1" location="src/test/java/com/aaravlabs/synapse/SubscriptionLifetimeTest.java:43">
P2: `assertEquals(List.of(1, 2), got)` asserts a fixed delivery order, but the two publishes are dispatched to the callback pool (ThreadPoolExecutor, core 4), where concurrent workers may complete the second task before the first. `TopicTest.subscribe_receivesPublishedValues` already documents that this exact ordering assertion made its test flaky and asserts membership instead. Assert size and set membership so the test only checks that both values were delivered.</violation>
<violation number="2" location="src/test/java/com/aaravlabs/synapse/SubscriptionLifetimeTest.java:93">
P2: Make `await` fail when its deadline expires; otherwise these tests can compare zero hits before and after removal and pass without exercising callback delivery.</violation>
</file>
<file name="src/main/java/com/aaravlabs/synapse/OrchestratorImpl.java">
<violation number="1" location="src/main/java/com/aaravlabs/synapse/OrchestratorImpl.java:200">
P3: `getOrCreateTopicUnchecked` duplicates the entire body of `getOrCreateTopic` — the same `requireNonNull` checks, the exists/`putIfAbsent` race branches, the identical error strings, and the `created topic` log — differing only in the two `safelyReturnsAs` blocks. The two registry paths can now drift: a future edit to topic creation (error text, a new check, logging) will silently apply to only one of them.</violation>
<violation number="2" location="src/main/java/com/aaravlabs/synapse/OrchestratorImpl.java:421">
P3: This explanation is technically incorrect: `Class.cast` does not return a boolean and throws for a primitive class. Describe the failed cast or thrown `ClassCastException` instead.</violation>
<violation number="3" location="src/main/java/com/aaravlabs/synapse/OrchestratorImpl.java:457">
P3: `removeSubscription` can still miss the hardware wrapper when it races the two-step registration in `markSubscriptionAsHardwareThreaded`. That method does `list.replace(original, wrapped)` and `hardwareRerouted.put(sub, wrapped)` as separate, unsynchronized operations (the put happens outside `SubscriberList`'s lock). If `unregisterNode`/`unsubscribe` runs between them, `getOrDefault` sees an empty map and falls back to `sub.handler()` (the original), which the replace has already removed from the list — the removal is a no-op and the wrapped `@OnHardwareThread` handler keeps receiving publishes, the exact leak this PR sets out to fix.</violation>
</file>
<file name="src/test/java/com/aaravlabs/synapse/TopicLockFreeTest.java">
<violation number="1" location="src/test/java/com/aaravlabs/synapse/TopicLockFreeTest.java:373">
P3: The failure message is inverted: this assertion fails when `second.ageNanos()` exceeds `first.ageNanos()`, i.e. the newer snapshot reports an *older* (larger) age. Saying "must not report a younger age" describes the passing case, which would mislead when debugging a failure. Change to "must not report an older age".</violation>
</file>
<file name="CHANGELOG.md">
<violation number="1" location="CHANGELOG.md:149">
P3: `findTopic(name, type)` and `getLatestValue(name, type)` reject unsafe requests by returning `Optional.empty()`; they do not emit a message. Limit the “with a message” wording to `getOrCreateTopic` so callers are not promised diagnostics these lookup APIs cannot provide.</violation>
</file>
…, test calibration Main source: - Serialize markSubscriptionAsHardwareThreaded and removeSubscription on a shared hardwareRerouteLock. The wrapper is recorded in two steps (list.replace, then the map put) and a removal landing between them read an empty map, fell back to the original handler the replace had already removed, and no-opped — re-opening the exact hardware-thread leak this PR closes. - SubscriberList.replace now reports whether it replaced anything, and the wrapper is recorded only on success. A second mark on an already-rerouted Subscription no-ops in replace(); recording its wrapper would point removeSubscription at a handler the list never held. - Route publish's lazy auto-create through getOrCreateTopicUnchecked. publish downcasts to Topic<Object> immediately and never exposes the topic as a Topic<T>, so the cast-safety rule would only make this path throw: a binder installing an Object-typed topic for a zero-argument @SubscribedTo handler between topics.get and the create made String.isAssignableFrom(Object) == false, dropping a publish that had always succeeded. - Collapse getOrCreateTopicUnchecked into getOrCreateTopic(name, type, castSafe) with a shared validateExisting. The duplicated body carried identical error strings, race branches, and the creation log, and was free to drift. - Correct the safelyReturnsAs javadoc: it checks the opposite assignability direction from acceptsType, so the two are complementary rather than one being stronger. - Correct the Class.cast comment: it throws for any non-null argument when the class is primitive (it is an isInstance check, and isInstance is false for wrappers), rather than "returning false". Tests: - await() fails on expiry instead of returning silently, and takes a named condition. A silent timeout let the removal tests compare zero hits against zero hits and pass with the callback never having run. - Add a control subscriber to both removal tests, never unregistered. Its arrival proves the post-removal publish was dispatched and the hardware thread was live, so "nothing arrived" means the subject was removed rather than the bus having gone quiet. Replaces the Thread.sleep(200)/sleep(400) scheduling assumptions, and asserts the positive control that a pre-removal delivery actually ran. - Assert set membership rather than delivery order in the primitive-subscribe test; publish dispatches to a four-worker pool, so ordering was never guaranteed. - Bound the ageNanos comparison by the measured span between the two clock samples, so independent sampling cannot produce a spurious ordering failure, and fix the inverted failure message. - Add coverage for publishing to a binder-created Object-typed topic, and state in the test what it does and does not pin (the defect itself needed a race to reach). 91 tests, 0 failures across 6 full-suite runs plus a 2-core pinned run. javadoc: 0 errors, no new warnings.
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1 issue found across 5 files (changes from recent commits).
Prompt for AI agents (unresolved issues)
Check if these issues are valid — if so, understand the root cause of each and fix them. When an issue isn't valid or won't be fixed in this PR, reply in its thread with the reason and then resolve the thread. If appropriate, use sub-agents to investigate and fix each issue separately.
<file name="src/test/java/com/aaravlabs/synapse/SubscriptionLifetimeTest.java">
<violation number="1" location="src/test/java/com/aaravlabs/synapse/SubscriptionLifetimeTest.java:43">
P2: `await(() -> got.size(), ...)` returns as soon as `got.size() > 0`, i.e. after the first of the two deliveries (dispatch is async on the callback pool), so `assertEquals(2, got.size())` on the next line races with the second callback and can fail spuriously. The previous version correctly awaited `>= 2`. Await the full count before asserting.</violation>
</file>
Reply with feedback, questions, or to request a fix.
Fix all with cubic | Re-trigger cubic
|
|
||
| orchestrator.publish("t", 1); | ||
| orchestrator.publish("t", 2); | ||
| await(() -> got.size(), "both published values must be delivered"); |
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P2: await(() -> got.size(), ...) returns as soon as got.size() > 0, i.e. after the first of the two deliveries (dispatch is async on the callback pool), so assertEquals(2, got.size()) on the next line races with the second callback and can fail spuriously. The previous version correctly awaited >= 2. Await the full count before asserting.
Prompt for AI agents
Check if this issue is valid — if so, understand the root cause and fix it. When an issue isn't valid or won't be fixed in this PR, reply in its thread with the reason and then resolve the thread. At src/test/java/com/aaravlabs/synapse/SubscriptionLifetimeTest.java, line 43:
<comment>`await(() -> got.size(), ...)` returns as soon as `got.size() > 0`, i.e. after the first of the two deliveries (dispatch is async on the callback pool), so `assertEquals(2, got.size())` on the next line races with the second callback and can fail spuriously. The previous version correctly awaited `>= 2`. Await the full count before asserting.</comment>
<file context>
@@ -38,9 +40,12 @@ void subscribeWithAPrimitiveClassStillDelivers() {
orchestrator.publish("t", 1);
orchestrator.publish("t", 2);
- await(() -> got.size() >= 2);
+ await(() -> got.size(), "both published values must be delivered");
- assertEquals(List.of(1, 2), got,
</file context>
Comment on lines
+178
to
+179
| await(control::get, | ||
| "the control must observe the post-unsubscribe publish, proving dispatch ran"); |
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Premature predicate satisfaction in src/test/java/com/aaravlabs/synapse/SubscriptionLifetimeTest.java:153-154 and src/test/java/com/aaravlabs/synapse/SubscriptionLifetimeTest.java:43-43: the pre-unsubscribe publish has already made control::get positive, so the await does not prove that dispatch ran after unsubscribe. Capture a baseline before the post-unsubscribe publish, wait for a strictly larger count, and use a deterministic barrier or calibrated bounded probe loop before relying on the subject's unchanged count.
Kody rule violation: Avoid Scheduler and Clock-Resolution Assumptions in Java Tests
await(() -> control.get() >= 2 ? 1 : 0,
"the control must observe a new post-unsubscribe publish");Prompt for LLM
File src/test/java/com/aaravlabs/synapse/SubscriptionLifetimeTest.java:
Line 178 to 179:
Premature predicate satisfaction in `src/test/java/com/aaravlabs/synapse/SubscriptionLifetimeTest.java:153-154` and `src/test/java/com/aaravlabs/synapse/SubscriptionLifetimeTest.java:43-43`: the pre-unsubscribe publish has already made `control::get` positive, so the await does not prove that dispatch ran after unsubscribe. Capture a baseline before the post-unsubscribe publish, wait for a strictly larger count, and use a deterministic barrier or calibrated bounded probe loop before relying on the subject's unchanged count.
Suggested Code:
await(() -> control.get() >= 2 ? 1 : 0,
"the control must observe a new post-unsubscribe publish");
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Comment on lines
+153
to
+154
| await(control::get, | ||
| "the control must observe the post-unregister publish, proving dispatch ran"); |
There was a problem hiding this comment.
Uncalibrated control at src/test/java/com/aaravlabs/synapse/SubscriptionLifetimeTest.java:178-179: the pre-unregister publish already satisfies await(control::get, ...), so the control does not prove that the operation under test was detected. Require a strictly increased control count, retain a deliberately known-bad control alongside a known-good or frozen quiet control, execute bounded repetitions, and report observed detection and miss rates instead of treating one green run as proof.
Kody rule violation: Calibrate Concurrency Detectors with Known-Good and Known-Bad Controls
Prompt for LLM
File src/test/java/com/aaravlabs/synapse/SubscriptionLifetimeTest.java:
Line 153 to 154:
Uncalibrated control at `src/test/java/com/aaravlabs/synapse/SubscriptionLifetimeTest.java:178-179`: the pre-unregister publish already satisfies `await(control::get, ...)`, so the control does not prove that the operation under test was detected. Require a strictly increased control count, retain a deliberately known-bad control alongside a known-good or frozen quiet control, execute bounded repetitions, and report observed detection and miss rates instead of treating one green run as proof.
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Comment on lines
+372
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| // would never exercise ageNanos at all. The two calls sample the clock separately, | ||
| // so the elapsed span between them is measured and allowed for: that span is the | ||
| // sampling skew, and only skew of that size could let the newer value report the | ||
| // older age. Clock readings either side keep the allowance honest rather than | ||
| // granting an unbounded tolerance. | ||
| long skewBefore = System.nanoTime(); | ||
| long secondAge = second.ageNanos(); | ||
| long firstAge = first.ageNanos(); | ||
| long skewAfter = System.nanoTime(); | ||
| long maxSkew = skewAfter - skewBefore; | ||
| assertTrue(secondAge <= firstAge + maxSkew, | ||
| "the newer value must not report an older age than the one it replaced: " | ||
| + secondAge + " vs " + firstAge + " (clock skew allowance " + maxSkew + ")"); |
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Clock-sampling skew in src/test/java/com/aaravlabs/synapse/TopicLockFreeTest.java: the outer skewBefore and skewAfter readings measure only elapsed time and do not turn the two internal System.nanoTime() samples into one logical observation. Bracket each ageNanos() call to validate that method, but derive both ages used for the ordering assertion from one shared System.nanoTime() value.
Kody rule violation: Use the Correct Clock Sampling Scope for Time Assertions
// each ageNanos() result below is validated against clock readings taken
// immediately around that call. Their independently sampled outputs are not
// compared; the ordering assertion uses ages derived from one shared observation.
long secondAgeBefore = System.nanoTime();
long secondAge = second.ageNanos();
long secondAgeAfter = System.nanoTime();
assertTrue(secondAge >= secondAgeBefore - second.publishNanos()
&& secondAge <= secondAgeAfter - second.publishNanos(),
"second ageNanos() is inconsistent with its publish stamp: " + secondAge);
long firstAgeBefore = System.nanoTime();
long firstAge = first.ageNanos();
long firstAgeAfter = System.nanoTime();
assertTrue(firstAge >= firstAgeBefore - first.publishNanos()
&& firstAge <= firstAgeAfter - first.publishNanos(),
"first ageNanos() is inconsistent with its publish stamp: " + firstAge);
long observedAt = System.nanoTime();
long secondAgeAtObservation = observedAt - second.publishNanos();
long firstAgeAtObservation = observedAt - first.publishNanos();
assertTrue(secondAgeAtObservation < firstAgeAtObservation,
"the newer value must have a smaller age at the same observation: "
+ secondAgeAtObservation + " vs " + firstAgeAtObservation);Prompt for LLM
File src/test/java/com/aaravlabs/synapse/TopicLockFreeTest.java:
Line 372 to 384:
Clock-sampling skew in `src/test/java/com/aaravlabs/synapse/TopicLockFreeTest.java`: the outer `skewBefore` and `skewAfter` readings measure only elapsed time and do not turn the two internal `System.nanoTime()` samples into one logical observation. Bracket each `ageNanos()` call to validate that method, but derive both ages used for the ordering assertion from one shared `System.nanoTime()` value.
Suggested Code:
// each ageNanos() result below is validated against clock readings taken
// immediately around that call. Their independently sampled outputs are not
// compared; the ordering assertion uses ages derived from one shared observation.
long secondAgeBefore = System.nanoTime();
long secondAge = second.ageNanos();
long secondAgeAfter = System.nanoTime();
assertTrue(secondAge >= secondAgeBefore - second.publishNanos()
&& secondAge <= secondAgeAfter - second.publishNanos(),
"second ageNanos() is inconsistent with its publish stamp: " + secondAge);
long firstAgeBefore = System.nanoTime();
long firstAge = first.ageNanos();
long firstAgeAfter = System.nanoTime();
assertTrue(firstAge >= firstAgeBefore - first.publishNanos()
&& firstAge <= firstAgeAfter - first.publishNanos(),
"first ageNanos() is inconsistent with its publish stamp: " + firstAge);
long observedAt = System.nanoTime();
long secondAgeAtObservation = observedAt - second.publishNanos();
long firstAgeAtObservation = observedAt - first.publishNanos();
assertTrue(secondAgeAtObservation < firstAgeAtObservation,
"the newer value must have a smaller age at the same observation: "
+ secondAgeAtObservation + " vs " + firstAgeAtObservation);
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Summary
An audit of the publish path (run after #29 and #31 merged) found three real defects, all reproduced against the real classes before being fixed. The most serious is a safety one: an unregistered node kept receiving publishes and could still drive hardware.
Also fixes the Docker workflow, which has been failing on
mainsince at leastce0f407.Defects
1.
unregisterNode/unsubscribedo not stop an@OnHardwareThreadsubscriberThe serious one.
markSubscriptionAsHardwareThreadedreplaces the entry in the subscriber list with a wrapper that submits to the hardware thread, butSubscription.handler()still returns the unwrapped handler.removeSubscriptionthen searched for something the list no longer held, andSubscriberList.removereturns silently on a miss.So an unregistered node kept receiving every publish. The hardware-thread pool is never shut down by
unregisterNode, so those callbacks kept running — an "unregistered" node could still write to motors.hardwareReroutedalready recorded the registered wrapper — it was written and never read.removeSubscriptionnow looks up whichever handler is actually in the list, and clears the entry so it cannot leak.2.
subscribe(name, int.class, handler)registers and then never firesClass.cast()returnsfalsefor every argument when the class is primitive. Sotype.cast(msg)threwClassCastExceptionon every delivery, anddispatchCallbackswallowed it into a log line: the subscriber was registered, never fired, and nothing indicated why.The library teaches primitive/wrapper equivalence everywhere else —
getOrCreateTopicacceptsint.classfor anIntegertopic, andacceptsTypeboxes before comparing — so this was reachable by following the library's own rule. The type is now boxed for the runtime check.3. Typed lookups hand back a value the caller cannot cast
acceptsTypeasksboxed(topicType).isAssignableFrom(boxed(requested)). For anObjecttopic that accepts a request forString— and the unchecked cast then failed at the caller's line, afterisPresent()had already reported a value:New
Topic.safelyReturnsAsis strictly stronger and refuses the request with a message naming the actual type. Narrowing to a type the topic really holds still works, andsubscribeRawstill accepts anObjecttopic — its handler receivesObject, which is the annotation binder's supported "several handlers, one topic" configuration (CoreHotPathTestcovers it).Docker workflow
Docker imagehas failed onmainfor six straight merges, including two before this work. Every build job recomputesIMAGEinto$GITHUB_ENVvia its own prepare step, which does not cross the job boundary — so the merge job's manifest step saw an emptyIMAGEand passed buildx a bare@sha256:..., rejected as an invalid reference.The published multi-arch image has not updated since at least
ce0f407. The merge job now recomputesIMAGEthe same way the build jobs do.Test quality
An independent audit of the new test suite found assertions that looked like they verified a property but would pass against a broken implementation. All confirmed by deliberately breaking the code:
latest()returning empty always — every check inside the reader was skippedassertEquals(latest().publishNanos(), latestPublishNanos())compares one volatile field with itselfassertEquals(acceptsValueClass(c), acceptsType(c))compares a method to itself, since one delegates to the otherageNanos()"younger age" check was algebraically a restatement of the preceding assertionageNanos()latestPublishNanos()had no test that could failThe external-clock window is the only form that cannot be satisfied by a skewed timestamp: a
Lateststamped withpublishNanos + Kshifts the age and both bounds together, so every self-referential check passes.One gap I could not close
The install-ordering guarantee in
recordLatest— that the monitor keeps install order equal to timestamp order — has no test, and I have documented why in the source rather than shipping one that misleads:Every arrangement either flakes, hangs, or cannot fire. A test that cannot fail reliably is worse than none. The guarantee rests on the monitor plus the reasoning recorded in the comment.
Verification
gradle test→ 91 tests, 0 failures (was 86; +5 new).gradle javadoc→ 0 errors, no new warnings.latestValue28 ns,recordLatest.1p1c196 ns.Review follow-up (
302099d)The three defects were fixed, but the fixes had gaps the review found. All are now
addressed; details are in the individual threads.
The removal fix could still miss. The hardware wrapper is recorded in two steps —
list.replace, then the map put — andremoveSubscriptionread the map outside anylock shared with the mark. A removal landing between the two read an empty map, fell
back to
sub.handler(), and no-opped against a handlerreplacehad already taken outof the list: the wrapper stayed registered and an unregistered node could still drive
the hardware, which is the leak this PR exists to close. Both now hold
hardwareRerouteLock. Separately, a secondmarkSubscriptionAsHardwareThreadedon analready-rerouted
Subscriptionrecorded its wrapper even thoughreplaceno-oped, soremoval pointed at a handler the list never held and left the first wrapper registered.
replacenow reports success and the record is conditional on it.The cast-safety rule broke
publish.publishdowncasts toTopic<Object>andnever exposes a topic as a
Topic<T>, but its lazy auto-create went through thecast-safe path. A binder installing an
Object-typed topic for a zero-argument@SubscribedTohandler — betweentopics.getand the create — madeString.isAssignableFrom(Object) == false, andpublishthrew on a path that hadalways succeeded. It now uses the unchecked variant; only genuinely typed lookups
enforce the rule.
The new tests could pass without testing anything.
awaitreturned silently at itsdeadline, so the two removal tests compared zero hits against zero hits and passed with
the callback never running. It now fails on expiry, and each test has a control
subscriber that is never removed: its arrival after the removal proves the publish was
dispatched and the pool was live, so "nothing arrived" can only mean the subject was
removed. That also removed the
Thread.sleep(200)scheduling assumptions. Theprimitive-subscribe test asserted a delivery order a four-worker pool does not
guarantee; it asserts membership now.
Two comments were wrong rather than incomplete:
safelyReturnsAswas documented as"strictly stronger" than
acceptsTypewhen it checks the opposite assignabilitydirection (they are complementary, and typed lookups need both), and the
Class.castcomment claimed it "returns false" for a primitive class when it throws. Both fixed,
along with a CHANGELOG line that promised a diagnostic message from the two lookup APIs
that return
Optional.empty()instead of one.One deviation worth naming: on the
ageNanos()assertion, deriving both ages from oneshared clock reading — as suggested — would never call
ageNanos()at all, which is theproperty that assertion exists to exercise. Instead the span between the two samples is
measured and used as a bounded tolerance, so the comparison is sound under independent
sampling without assuming the reads were simultaneous.
One honest limit:
publishToABinderCreatedObjectTopicStillSucceedspins the behaviour arevert would break, but the defect itself was only reachable through a race, so the test
does not detect a revert of that one line. The test says so in a comment.
Summary by Sourcery
Fix subscription cleanup and type-safety issues in the publish path, and repair Docker image publication.
Bug Fixes:
Enhancements:
CI:
Documentation:
Tests: