The Gold Standard of Websites | Tracing disposeAsync Await Boundaries Across Mixed Cleanup Records

disposeAsync is an async method: calling it returns a Promise, while the internal algorithm changes state and runs disposal work whose completion the caller observes through that Promise. Start the trace with the current cleanup record, its returned value or Promise, the stack state, the active Await boundary, the carried completion and the caller waiting on disposeAsync. Write those facts down before reading the final console line, returned Promise or thrown value.

Worked example. Call const done=stack.disposeAsync(), log immediately, then await done and log again with one gated cleanup record. Use distinct event labels for acquisition, method lookup, record creation, state change, cleanup call, settlement and caller observation. This makes the example checkable rather than impressionistic.

Reason through the sequence one operation at a time. Identify the algorithm step that selects the branch, record which cleanup entries remain live, and mark whether execution is synchronous, suspended at an Await, fulfilled or rejected. Only then interpret the visible result.

Changed-context transfer check. Remove the await at the call site and show why later code can run before cleanup completion. Rebuild the complete event list from the changed premise. State the first line at which it diverges and follow both paths to their final cleanup state.

Limit and misconception check. A returned Promise is not evidence that cleanup has already finished. Keep the conclusion tied to the stated fixture. Proxies, host resources, re-entrant cleanup, application-specific idempotence and implementation defects can add observations that this focused model does not promise to predict.

Practical evidence check. Instrument each getter, callback and disposal method with a unique label; capture its receiver and arguments; expose the disposed state where the API does; and await the returned Promise before asserting the full ordered log. A test of only the last message can miss a wrong owner or a skipped cleanup.

Use three layers when reviewing code. The resource defines what release means. The language construct or stack decides when, in what order and with which captured function release runs. The caller observes completion or failure. Keeping the layers separate prevents a timing observation from being misreported as a resource rule.

Transfer the reasoning into a short answer: give the starting state, decisive rule, ordered result and one caveat. Then change one feature and name the earliest changed step. That structure is concise enough for revision and strong enough for a code review.

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The algorithm checks state, sets it to disposed, and only then delegates to DisposeResources. Start the trace with the current cleanup record, its returned value or Promise, the stack state, the active Await boundary, the carried completion and the caller waiting on disposeAsync. Write those facts down before reading the final console line, returned Promise or thrown value.

Worked example. Use a cleanup promise that remains pending; read stack.disposed while it is blocked and observe true. Use distinct event labels for acquisition, method lookup, record creation, state change, cleanup call, settlement and caller observation. This makes the example checkable rather than impressionistic.

Reason through the sequence one operation at a time. Identify the algorithm step that selects the branch, record which cleanup entries remain live, and mark whether execution is synchronous, suspended at an Await, fulfilled or rejected. Only then interpret the visible result.

Changed-context transfer check. Read disposed before calling disposeAsync and compare the pending-to-disposed transition. Rebuild the complete event list from the changed premise. State the first line at which it diverges and follow both paths to their final cleanup state.

Limit and misconception check. disposed means the container will accept no new records; it does not mean every resource has settled its cleanup. Keep the conclusion tied to the stated fixture. Proxies, host resources, re-entrant cleanup, application-specific idempotence and implementation defects can add observations that this focused model does not promise to predict.

Practical evidence check. Instrument each getter, callback and disposal method with a unique label; capture its receiver and arguments; expose the disposed state where the API does; and await the returned Promise before asserting the full ordered log. A test of only the last message can miss a wrong owner or a skipped cleanup.

Use three layers when reviewing code. The resource defines what release means. The language construct or stack decides when, in what order and with which captured function release runs. The caller observes completion or failure. Keeping the layers separate prevents a timing observation from being misreported as a resource rule.

Transfer the reasoning into a short answer: give the starting state, decisive rule, ordered result and one caveat. Then change one feature and name the earliest changed step. That structure is concise enough for revision and strong enough for a code review.

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DisposeResources visits the list in reverse registration order, so the newest record is called first. Start the trace with the current cleanup record, its returned value or Promise, the stack state, the active Await boundary, the carried completion and the caller waiting on disposeAsync. Write those facts down before reading the final console line, returned Promise or thrown value.

Worked example. Register A, B and C with unique start and finish logs; C-start appears before any B event. Use distinct event labels for acquisition, method lookup, record creation, state change, cleanup call, settlement and caller observation. This makes the example checkable rather than impressionistic.

Reason through the sequence one operation at a time. Identify the algorithm step that selects the branch, record which cleanup entries remain live, and mark whether execution is synchronous, suspended at an Await, fulfilled or rejected. Only then interpret the visible result.

Changed-context transfer check. Swap B and C registration and rebuild the expected start order. Rebuild the complete event list from the changed premise. State the first line at which it diverges and follow both paths to their final cleanup state.

Limit and misconception check. Reverse order concerns records, not chronological resource acquisition elsewhere. Keep the conclusion tied to the stated fixture. Proxies, host resources, re-entrant cleanup, application-specific idempotence and implementation defects can add observations that this focused model does not promise to predict.

Practical evidence check. Instrument each getter, callback and disposal method with a unique label; capture its receiver and arguments; expose the disposed state where the API does; and await the returned Promise before asserting the full ordered log. A test of only the last message can miss a wrong owner or a skipped cleanup.

Use three layers when reviewing code. The resource defines what release means. The language construct or stack decides when, in what order and with which captured function release runs. The caller observes completion or failure. Keeping the layers separate prevents a timing observation from being misreported as a resource rule.

Transfer the reasoning into a short answer: give the starting state, decisive rule, ordered result and one caveat. Then change one feature and name the earliest changed step. That structure is concise enough for revision and strong enough for a code review.

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When an async-dispose cleanup returns a pending Promise, the algorithm awaits it before advancing to the next older record. Start the trace with the current cleanup record, its returned value or Promise, the stack state, the active Await boundary, the carried completion and the caller waiting on disposeAsync. Write those facts down before reading the final console line, returned Promise or thrown value.

Worked example. Hold C pending and confirm B-start and A-start are absent until C resolves. Use distinct event labels for acquisition, method lookup, record creation, state change, cleanup call, settlement and caller observation. This makes the example checkable rather than impressionistic.

Reason through the sequence one operation at a time. Identify the algorithm step that selects the branch, record which cleanup entries remain live, and mark whether execution is synchronous, suspended at an Await, fulfilled or rejected. Only then interpret the visible result.

Changed-context transfer check. Resolve C but hold B; observe the boundary move down one record. Rebuild the complete event list from the changed premise. State the first line at which it diverges and follow both paths to their final cleanup state.

Limit and misconception check. The stack does not launch all cleanups concurrently. Keep the conclusion tied to the stated fixture. Proxies, host resources, re-entrant cleanup, application-specific idempotence and implementation defects can add observations that this focused model does not promise to predict.

Practical evidence check. Instrument each getter, callback and disposal method with a unique label; capture its receiver and arguments; expose the disposed state where the API does; and await the returned Promise before asserting the full ordered log. A test of only the last message can miss a wrong owner or a skipped cleanup.

Use three layers when reviewing code. The resource defines what release means. The language construct or stack decides when, in what order and with which captured function release runs. The caller observes completion or failure. Keeping the layers separate prevents a timing observation from being misreported as a resource rule.

Transfer the reasoning into a short answer: give the starting state, decisive rule, ordered result and one caveat. Then change one feature and name the earliest changed step. That structure is concise enough for revision and strong enough for a code review.

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An immediately fulfilled Promise still passes through Await, even though it does not introduce an externally controlled delay. Start the trace with the current cleanup record, its returned value or Promise, the stack state, the active Await boundary, the carried completion and the caller waiting on disposeAsync. Write those facts down before reading the final console line, returned Promise or thrown value.

Worked example. Return Promise.resolve() from C and compare synchronous call logs with a microtask placed after disposeAsync is invoked. Use distinct event labels for acquisition, method lookup, record creation, state change, cleanup call, settlement and caller observation. This makes the example checkable rather than impressionistic.

Reason through the sequence one operation at a time. Identify the algorithm step that selects the branch, record which cleanup entries remain live, and mark whether execution is synchronous, suspended at an Await, fulfilled or rejected. Only then interpret the visible result.

Changed-context transfer check. Return a manually gated promise and identify the additional observable delay. Rebuild the complete event list from the changed premise. State the first line at which it diverges and follow both paths to their final cleanup state.

Limit and misconception check. Immediate settlement and synchronous completion are not the same observation. Keep the conclusion tied to the stated fixture. Proxies, host resources, re-entrant cleanup, application-specific idempotence and implementation defects can add observations that this focused model does not promise to predict.

Practical evidence check. Instrument each getter, callback and disposal method with a unique label; capture its receiver and arguments; expose the disposed state where the API does; and await the returned Promise before asserting the full ordered log. A test of only the last message can miss a wrong owner or a skipped cleanup.

Use three layers when reviewing code. The resource defines what release means. The language construct or stack decides when, in what order and with which captured function release runs. The caller observes completion or failure. Keeping the layers separate prevents a timing observation from being misreported as a resource rule.

Transfer the reasoning into a short answer: give the starting state, decisive rule, ordered result and one caveat. Then change one feature and name the earliest changed step. That structure is concise enough for revision and strong enough for a code review.

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Await follows the normal thenable assimilation rules for a value returned by an async-dispose callback. Start the trace with the current cleanup record, its returned value or Promise, the stack state, the active Await boundary, the carried completion and the caller waiting on disposeAsync. Write those facts down before reading the final console line, returned Promise or thrown value.

Worked example. Have an adopted callback return a thenable whose then getter and invocation log separately; trace both before B begins. Use distinct event labels for acquisition, method lookup, record creation, state change, cleanup call, settlement and caller observation. This makes the example checkable rather than impressionistic.

Reason through the sequence one operation at a time. Identify the algorithm step that selects the branch, record which cleanup entries remain live, and mark whether execution is synchronous, suspended at an Await, fulfilled or rejected. Only then interpret the visible result.

Changed-context transfer check. Return a plain number and compare the shorter settlement path. Rebuild the complete event list from the changed premise. State the first line at which it diverges and follow both paths to their final cleanup state.

Limit and misconception check. A thenable can run observable user code during assimilation, so “returns a value” is too coarse a description. Keep the conclusion tied to the stated fixture. Proxies, host resources, re-entrant cleanup, application-specific idempotence and implementation defects can add observations that this focused model does not promise to predict.

Practical evidence check. Instrument each getter, callback and disposal method with a unique label; capture its receiver and arguments; expose the disposed state where the API does; and await the returned Promise before asserting the full ordered log. A test of only the last message can miss a wrong owner or a skipped cleanup.

Use three layers when reviewing code. The resource defines what release means. The language construct or stack decides when, in what order and with which captured function release runs. The caller observes completion or failure. Keeping the layers separate prevents a timing observation from being misreported as a resource rule.

Transfer the reasoning into a short answer: give the starting state, decisive rule, ordered result and one caveat. Then change one feature and name the earliest changed step. That structure is concise enough for revision and strong enough for a code review.

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adopt stores a wrapper that calls onDisposeAsync with the captured value; DisposeResources awaits whatever that callback returns. Start the trace with the current cleanup record, its returned value or Promise, the stack state, the active Await boundary, the carried completion and the caller waiting on disposeAsync. Write those facts down before reading the final console line, returned Promise or thrown value.

Worked example. Adopt token T with a callback that starts a network-release simulation and resolves on a gate; older cleanup waits. Use distinct event labels for acquisition, method lookup, record creation, state change, cleanup call, settlement and caller observation. This makes the example checkable rather than impressionistic.

Reason through the sequence one operation at a time. Identify the algorithm step that selects the branch, record which cleanup entries remain live, and mark whether execution is synchronous, suspended at an Await, fulfilled or rejected. Only then interpret the visible result.

Changed-context transfer check. Make the callback return undefined and compare the required Await with no external gate. Rebuild the complete event list from the changed premise. State the first line at which it diverges and follow both paths to their final cleanup state.

Limit and misconception check. The adopted token is an argument to the callback, not the receiver of the stored wrapper. Keep the conclusion tied to the stated fixture. Proxies, host resources, re-entrant cleanup, application-specific idempotence and implementation defects can add observations that this focused model does not promise to predict.

Practical evidence check. Instrument each getter, callback and disposal method with a unique label; capture its receiver and arguments; expose the disposed state where the API does; and await the returned Promise before asserting the full ordered log. A test of only the last message can miss a wrong owner or a skipped cleanup.

Use three layers when reviewing code. The resource defines what release means. The language construct or stack decides when, in what order and with which captured function release runs. The caller observes completion or failure. Keeping the layers separate prevents a timing observation from being misreported as a resource rule.

Transfer the reasoning into a short answer: give the starting state, decisive rule, ordered result and one caveat. Then change one feature and name the earliest changed step. That structure is concise enough for revision and strong enough for a code review.

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defer stores the callback directly as an async-dispose method and its result is awaited in reverse order. Start the trace with the current cleanup record, its returned value or Promise, the stack state, the active Await boundary, the carried completion and the caller waiting on disposeAsync. Write those facts down before reading the final console line, returned Promise or thrown value.

Worked example. Defer C, B and A callbacks with different gates; prove each gate must resolve before the next callback begins. Use distinct event labels for acquisition, method lookup, record creation, state change, cleanup call, settlement and caller observation. This makes the example checkable rather than impressionistic.

Reason through the sequence one operation at a time. Identify the algorithm step that selects the branch, record which cleanup entries remain live, and mark whether execution is synchronous, suspended at an Await, fulfilled or rejected. Only then interpret the visible result.

Changed-context transfer check. Make B throw synchronously and compare the rejected completion with a returned rejected Promise. Rebuild the complete event list from the changed premise. State the first line at which it diverges and follow both paths to their final cleanup state.

Limit and misconception check. Synchronous throwing and Promise rejection have different immediate traces but both become cleanup failure observations. Keep the conclusion tied to the stated fixture. Proxies, host resources, re-entrant cleanup, application-specific idempotence and implementation defects can add observations that this focused model does not promise to predict.

Practical evidence check. Instrument each getter, callback and disposal method with a unique label; capture its receiver and arguments; expose the disposed state where the API does; and await the returned Promise before asserting the full ordered log. A test of only the last message can miss a wrong owner or a skipped cleanup.

Use three layers when reviewing code. The resource defines what release means. The language construct or stack decides when, in what order and with which captured function release runs. The caller observes completion or failure. Keeping the layers separate prevents a timing observation from being misreported as a resource rule.

Transfer the reasoning into a short answer: give the starting state, decisive rule, ordered result and one caveat. Then change one feature and name the earliest changed step. That structure is concise enough for revision and strong enough for a code review.

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An empty pending stack is marked disposed and returns normal completion through the async method; an already disposed stack also returns normally. Start the trace with the current cleanup record, its returned value or Promise, the stack state, the active Await boundary, the carried completion and the caller waiting on disposeAsync. Write those facts down before reading the final console line, returned Promise or thrown value.

Worked example. Call disposeAsync twice on an empty stack and await both returned Promises while logging state. Use distinct event labels for acquisition, method lookup, record creation, state change, cleanup call, settlement and caller observation. This makes the example checkable rather than impressionistic.

Reason through the sequence one operation at a time. Identify the algorithm step that selects the branch, record which cleanup entries remain live, and mark whether execution is synchronous, suspended at an Await, fulfilled or rejected. Only then interpret the visible result.

Changed-context transfer check. Add one immediate callback before the first call and compare the additional cleanup event. Rebuild the complete event list from the changed premise. State the first line at which it diverges and follow both paths to their final cleanup state.

Limit and misconception check. Idempotent disposal does not make later registration legal. Keep the conclusion tied to the stated fixture. Proxies, host resources, re-entrant cleanup, application-specific idempotence and implementation defects can add observations that this focused model does not promise to predict.

Practical evidence check. Instrument each getter, callback and disposal method with a unique label; capture its receiver and arguments; expose the disposed state where the API does; and await the returned Promise before asserting the full ordered log. A test of only the last message can miss a wrong owner or a skipped cleanup.

Use three layers when reviewing code. The resource defines what release means. The language construct or stack decides when, in what order and with which captured function release runs. The caller observes completion or failure. Keeping the layers separate prevents a timing observation from being misreported as a resource rule.

Transfer the reasoning into a short answer: give the starting state, decisive rule, ordered result and one caveat. Then change one feature and name the earliest changed step. That structure is concise enough for revision and strong enough for a code review.

Contents · Previous chapter · Next chapter

A rejected cleanup changes the carried completion, but DisposeResources still processes older records. Start the trace with the current cleanup record, its returned value or Promise, the stack state, the active Await boundary, the carried completion and the caller waiting on disposeAsync. Write those facts down before reading the final console line, returned Promise or thrown value.

Worked example. Let C reject, B resolve and A log; all are attempted before the returned Promise rejects. Use distinct event labels for acquisition, method lookup, record creation, state change, cleanup call, settlement and caller observation. This makes the example checkable rather than impressionistic.

Reason through the sequence one operation at a time. Identify the algorithm step that selects the branch, record which cleanup entries remain live, and mark whether execution is synchronous, suspended at an Await, fulfilled or rejected. Only then interpret the visible result.

Changed-context transfer check. Make B reject as well and inspect the nested suppression result. Rebuild the complete event list from the changed premise. State the first line at which it diverges and follow both paths to their final cleanup state.

Limit and misconception check. Failure is not a cancellation signal for the remaining cleanup records. Keep the conclusion tied to the stated fixture. Proxies, host resources, re-entrant cleanup, application-specific idempotence and implementation defects can add observations that this focused model does not promise to predict.

Practical evidence check. Instrument each getter, callback and disposal method with a unique label; capture its receiver and arguments; expose the disposed state where the API does; and await the returned Promise before asserting the full ordered log. A test of only the last message can miss a wrong owner or a skipped cleanup.

Use three layers when reviewing code. The resource defines what release means. The language construct or stack decides when, in what order and with which captured function release runs. The caller observes completion or failure. Keeping the layers separate prevents a timing observation from being misreported as a resource rule.

Transfer the reasoning into a short answer: give the starting state, decisive rule, ordered result and one caveat. Then change one feature and name the earliest changed step. That structure is concise enough for revision and strong enough for a code review.

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A callback may throw before returning or return a Promise that rejects later; both fail cleanup, but their event boundaries differ. Start the trace with the current cleanup record, its returned value or Promise, the stack state, the active Await boundary, the carried completion and the caller waiting on disposeAsync. Write those facts down before reading the final console line, returned Promise or thrown value.

Worked example. Use two deferred callbacks, one throwing immediately and one rejecting after a gate, and label call, throw, reject and caller catch. Use distinct event labels for acquisition, method lookup, record creation, state change, cleanup call, settlement and caller observation. This makes the example checkable rather than impressionistic.

Reason through the sequence one operation at a time. Identify the algorithm step that selects the branch, record which cleanup entries remain live, and mark whether execution is synchronous, suspended at an Await, fulfilled or rejected. Only then interpret the visible result.

Changed-context transfer check. Convert the immediate throw into Promise.reject and find the earliest changed event. Rebuild the complete event list from the changed premise. State the first line at which it diverges and follow both paths to their final cleanup state.

Limit and misconception check. Matching final error text does not prove matching timing. Keep the conclusion tied to the stated fixture. Proxies, host resources, re-entrant cleanup, application-specific idempotence and implementation defects can add observations that this focused model does not promise to predict.

Practical evidence check. Instrument each getter, callback and disposal method with a unique label; capture its receiver and arguments; expose the disposed state where the API does; and await the returned Promise before asserting the full ordered log. A test of only the last message can miss a wrong owner or a skipped cleanup.

Use three layers when reviewing code. The resource defines what release means. The language construct or stack decides when, in what order and with which captured function release runs. The caller observes completion or failure. Keeping the layers separate prevents a timing observation from being misreported as a resource rule.

Transfer the reasoning into a short answer: give the starting state, decisive rule, ordered result and one caveat. Then change one feature and name the earliest changed step. That structure is concise enough for revision and strong enough for a code review.

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The caller can rely on all records having been attempted only after awaiting the Promise returned by disposeAsync. Start the trace with the current cleanup record, its returned value or Promise, the stack state, the active Await boundary, the carried completion and the caller waiting on disposeAsync. Write those facts down before reading the final console line, returned Promise or thrown value.

Worked example. Close a simulated file, lock and stream, then publish a “released” status only after await stack.disposeAsync(). Use distinct event labels for acquisition, method lookup, record creation, state change, cleanup call, settlement and caller observation. This makes the example checkable rather than impressionistic.

Reason through the sequence one operation at a time. Identify the algorithm step that selects the branch, record which cleanup entries remain live, and mark whether execution is synchronous, suspended at an Await, fulfilled or rejected. Only then interpret the visible result.

Changed-context transfer check. Move the status update before the await and show the false early signal. Rebuild the complete event list from the changed premise. State the first line at which it diverges and follow both paths to their final cleanup state.

Limit and misconception check. Application release functions may have extra durability guarantees that the language construct alone does not supply. Keep the conclusion tied to the stated fixture. Proxies, host resources, re-entrant cleanup, application-specific idempotence and implementation defects can add observations that this focused model does not promise to predict.

Practical evidence check. Instrument each getter, callback and disposal method with a unique label; capture its receiver and arguments; expose the disposed state where the API does; and await the returned Promise before asserting the full ordered log. A test of only the last message can miss a wrong owner or a skipped cleanup.

Use three layers when reviewing code. The resource defines what release means. The language construct or stack decides when, in what order and with which captured function release runs. The caller observes completion or failure. Keeping the layers separate prevents a timing observation from being misreported as a resource rule.

Transfer the reasoning into a short answer: give the starting state, decisive rule, ordered result and one caveat. Then change one feature and name the earliest changed step. That structure is concise enough for revision and strong enough for a code review.

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A controlled gate is stronger evidence than arbitrary timeouts because it names exactly which cleanup remains pending. Start the trace with the current cleanup record, its returned value or Promise, the stack state, the active Await boundary, the carried completion and the caller waiting on disposeAsync. Write those facts down before reading the final console line, returned Promise or thrown value.

Worked example. Give C and B independent resolvers, assert the log at each pause, then release them one by one. Use distinct event labels for acquisition, method lookup, record creation, state change, cleanup call, settlement and caller observation. This makes the example checkable rather than impressionistic.

Reason through the sequence one operation at a time. Identify the algorithm step that selects the branch, record which cleanup entries remain live, and mark whether execution is synchronous, suspended at an Await, fulfilled or rejected. Only then interpret the visible result.

Changed-context transfer check. Replace the gates with setTimeout and explain why scheduling noise weakens the test. Rebuild the complete event list from the changed premise. State the first line at which it diverges and follow both paths to their final cleanup state.

Limit and misconception check. One engine experiment checks that engine version; it does not replace the specification. Keep the conclusion tied to the stated fixture. Proxies, host resources, re-entrant cleanup, application-specific idempotence and implementation defects can add observations that this focused model does not promise to predict.

Practical evidence check. Instrument each getter, callback and disposal method with a unique label; capture its receiver and arguments; expose the disposed state where the API does; and await the returned Promise before asserting the full ordered log. A test of only the last message can miss a wrong owner or a skipped cleanup.

Use three layers when reviewing code. The resource defines what release means. The language construct or stack decides when, in what order and with which captured function release runs. The caller observes completion or failure. Keeping the layers separate prevents a timing observation from being misreported as a resource rule.

Transfer the reasoning into a short answer: give the starting state, decisive rule, ordered result and one caveat. Then change one feature and name the earliest changed step. That structure is concise enough for revision and strong enough for a code review.

Contents · Previous chapter · Next chapter

The state becomes disposed before cleanup settles, so a re-entrant disposeAsync call returns normally rather than starting another traversal. Start the trace with the current cleanup record, its returned value or Promise, the stack state, the active Await boundary, the carried completion and the caller waiting on disposeAsync. Write those facts down before reading the final console line, returned Promise or thrown value.

Worked example. From C cleanup call stack.disposeAsync() again, await the inner result and verify that A and B are still handled by the original traversal. Use distinct event labels for acquisition, method lookup, record creation, state change, cleanup call, settlement and caller observation. This makes the example checkable rather than impressionistic.

Reason through the sequence one operation at a time. Identify the algorithm step that selects the branch, record which cleanup entries remain live, and mark whether execution is synchronous, suspended at an Await, fulfilled or rejected. Only then interpret the visible result.

Changed-context transfer check. Call a registration method re-entrantly and observe ReferenceError instead. Rebuild the complete event list from the changed premise. State the first line at which it diverges and follow both paths to their final cleanup state.

Limit and misconception check. Re-entrant application callbacks can still create their own resources outside this stack. Keep the conclusion tied to the stated fixture. Proxies, host resources, re-entrant cleanup, application-specific idempotence and implementation defects can add observations that this focused model does not promise to predict.

Practical evidence check. Instrument each getter, callback and disposal method with a unique label; capture its receiver and arguments; expose the disposed state where the API does; and await the returned Promise before asserting the full ordered log. A test of only the last message can miss a wrong owner or a skipped cleanup.

Use three layers when reviewing code. The resource defines what release means. The language construct or stack decides when, in what order and with which captured function release runs. The caller observes completion or failure. Keeping the layers separate prevents a timing observation from being misreported as a resource rule.

Transfer the reasoning into a short answer: give the starting state, decisive rule, ordered result and one caveat. Then change one feature and name the earliest changed step. That structure is concise enough for revision and strong enough for a code review.

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A precise explanation names call time, state change, each cleanup call, each Await settlement and final caller observation. Start the trace with the current cleanup record, its returned value or Promise, the stack state, the active Await boundary, the carried completion and the caller waiting on disposeAsync. Write those facts down before reading the final console line, returned Promise or thrown value.

Worked example. Report C-call, C-settle, B-call, B-settle, A-call, A-settle, returned-Promise fulfillment. Use distinct event labels for acquisition, method lookup, record creation, state change, cleanup call, settlement and caller observation. This makes the example checkable rather than impressionistic.

Reason through the sequence one operation at a time. Identify the algorithm step that selects the branch, record which cleanup entries remain live, and mark whether execution is synchronous, suspended at an Await, fulfilled or rejected. Only then interpret the visible result.

Changed-context transfer check. Make B reject and explain how the sequence continues but final settlement changes. Rebuild the complete event list from the changed premise. State the first line at which it diverges and follow both paths to their final cleanup state.

Limit and misconception check. Avoid saying cleanup happens later without identifying which operation or Promise creates the delay. Keep the conclusion tied to the stated fixture. Proxies, host resources, re-entrant cleanup, application-specific idempotence and implementation defects can add observations that this focused model does not promise to predict.

Practical evidence check. Instrument each getter, callback and disposal method with a unique label; capture its receiver and arguments; expose the disposed state where the API does; and await the returned Promise before asserting the full ordered log. A test of only the last message can miss a wrong owner or a skipped cleanup.

Use three layers when reviewing code. The resource defines what release means. The language construct or stack decides when, in what order and with which captured function release runs. The caller observes completion or failure. Keeping the layers separate prevents a timing observation from being misreported as a resource rule.

Transfer the reasoning into a short answer: give the starting state, decisive rule, ordered result and one caveat. Then change one feature and name the earliest changed step. That structure is concise enough for revision and strong enough for a code review.

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