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fix(db): keep a live query running when a lazy demand fails during a truncate replay - #2231
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…its live query A marker truncate privately moved an ordered window, so an include's demand changed keys. The demand controller released the old segment first; that was the subscription's last demand, so its truncate replay ended, and the new demand started outside it. Its failure then ended the query with error 228. - Start new demand coverage before releasing retired coverage. - Open a replay at every truncate for a query subscription that acquires, even without demand, so demand the commit starts belongs to it. - A demand failure that fails its subscription's replay records the error and keeps the last publication instead of ending the query. The replay-refinement oracle now classifies recovery loads by request data (replay loads ask again with the same `where`) and by the commit window, and requires the campaigns to reach replay loads. Co-authored-by: Isaac <no-reply@databricks.com>
…res fatal Review fixes on top of the replay-failure change: - A recovery failure before the live query first becomes ready still ends it, so preload no longer waits for a later truncate. - A replay opened without demand starts no recovery work and reports no loading, so a zero-limit ordered window issues no full-source read. - A rejected aborted lazy demand request is obsolete demand: its truncate replay decides it even when the replay settled first, and a segment that newer coverage replaced settles. Both cases ended the query on main when the adapter rejected an aborted request with AbortError. The replay-refinement oracle now generates histories during the initial preload, aborted marker loads that reject, and newest-first settles, with an initial-readiness law; the ordered-lifecycle oracle checks truncate work. Co-authored-by: Isaac <no-reply@databricks.com>
Co-authored-by: Isaac <no-reply@databricks.com>
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| Check name | Status | Explanation | Resolution |
|---|---|---|---|
| Out of Scope Changes check |  |
The ordered page-end repair is unrelated to #2224. ordered-source-loader.ts adds revalidateLoadedCoverage, ownPrefixEnd, and loadMovedEndTie for a separate signalling-refetch defect with no tr… |
Remove the ordered page-end repair and its dedicated tests, oracle changes, documentation, changeset text, and mangle-cache.json entries, or move them to a separate pull request linked to an issue for that defect. Also provide a concrete … |
| Docstring Coverage | |
Docstring coverage is 50.00% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 10 functions across 10 files. | Write docstrings for the functions missing them to satisfy the coverage threshold. |
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Check name Status Explanation Title check The title clearly identifies the primary change: preserving a live query when lazy demand fails during truncate replay. It is specific and related to the main production change. Linked Issues check Issue #2224is the only active directly linked issue. The production changes address its shrunk history.subset-demand-controller.tsstarts replacement demand before releasing obsolete demand. `subs…Description check The description is comprehensive and covers the changes, motivation, oracle coverage, bug-class closure, known limits, verification results, and release impact. It does not use the exact template head… Full details: Linked Issues check
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Explanation
Issue
#2224is the only active directly linked issue. The production changes address its shrunk history.subset-demand-controller.tsstarts replacement demand before releasing obsolete demand.subscription.tsopens a truncate replay for acquiring on-demand subscriptions.collection-subscriber.tsandcollection-config-builder.tskeep a failed replay demand non-fatal after the query is ready, while failures duringloadingremain fatal. The replay-refinement oracle now models recovery ownership and covers the reported seed and path. The reported named replay passes on this branch.
Full details: Description check
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Explanation
The description is comprehensive and covers the changes, motivation, oracle coverage, bug-class closure, known limits, verification results, and release impact. It does not use the exact template headings or explicitly mark the checklist and release-impact checkboxes, but the required information is present, including a changeset and successful test results.
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Full details: Out of Scope Changes check
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Explanation
The ordered page-end repair is unrelated to
#2224.ordered-source-loader.tsaddsrevalidateLoadedCoverage,ownPrefixEnd, andloadMovedEndTiefor a separate signalling-refetch defect with no truncate replay or terminal query error. The related oracle laws, Query DB test, architecture and coverage documentation, changeset entry, andmangle-cache.jsonupdates support that separate behavior. The PR also includes a separate discarded-replay window-move fix; its connection to the linked counterexample is not established, although it is adjacent to replay handling.Resolution
Remove the ordered page-end repair and its dedicated tests, oracle changes, documentation, changeset text, and
mangle-cache.jsonentries, or move them to a separate pull request linked to an issue for that defect. Also provide a concrete#2224connection for the discarded-replay window-move change or move that change to the related pull request.
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Incremental update benchmarkComparing Overall median write time vs base: 1.03× · cold hydrate time: 0.97× (geometric mean of per-case ratios; lower is faster). Writes: 1 regression(s), 0 improvement(s) (threshold: ±20% and >0.05ms). Cold hydrate: No significant changes (threshold: ±50% and >5ms). Per-case flags are noisy on shared runners. Read the geometric means first. Writes
Cold hydrate
Each row aggregates the 14.4 scale/index/write-mode configurations of that query; per-configuration tables below. 100 rows/collection | source indexes: none | synced writes — geomean 1.04×, cold 1.07×
100 rows/collection | source indexes: none | optimistic writes — geomean 1.03×, cold 0.73×
100 rows/collection | source indexes: manual | synced writes — geomean 0.96×, cold 0.97×
100 rows/collection | source indexes: manual | optimistic writes — geomean 1.00×, cold 1.00×
1,000 rows/collection | source indexes: none | synced writes — geomean 1.15×, cold 1.14×, 1 change(s)
1,000 rows/collection | source indexes: none | optimistic writes — geomean 1.00×, cold 0.84×
1,000 rows/collection | source indexes: manual | synced writes — geomean 1.05×, cold 0.94×
1,000 rows/collection | source indexes: manual | optimistic writes — geomean 1.03×, cold 1.04×
10,000 rows/collection | source indexes: none | synced writes — geomean 1.03×, cold 0.95×
10,000 rows/collection | source indexes: none | optimistic writes — geomean 1.05×, cold 1.19×
10,000 rows/collection | source indexes: manual | synced writes — geomean 0.96×, cold 0.79×
10,000 rows/collection | source indexes: manual | optimistic writes — geomean 1.04×, cold 1.16×
Runner: node v24.8.0, linux 6.17.0-1022-azure, AMD EPYC 7763 64-Core Processor. Timings on shared CI runners are noisy; treat small deltas as indicative only. |
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Size Change: +988 B (+0.45%) Total Size: 221 kB 📦 View Changed
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…ts tie A signalling refetch can move the first page's end earlier, to a rank that a row the provider never sent ties with. The loader ignored the report because an installed row past the page sorted after the new end, but that row was there only because an older tie request read it. A later window move then read local rows and skipped the unsent row. The loader now takes an installed row past the page as evidence only when its own page read it or when it read the tie of the page's current end. The ordered-work oracle keeps the trace as a named replay; the request-authority oracle gains an unproven-report law. Both fail on main. Co-authored-by: Isaac <no-reply@databricks.com>
Co-authored-by: Isaac <no-reply@databricks.com>
…es deferred behind a discarded replay Ordered loading after a signalling refetch: - When a report shows that the first page's end moved, the loader now reads only the new end's tie on the next pass instead of a bounded repair, and releases the older tie without treating its deletes as an order change. Query DB's top-N insert costs one tie request and keeps its active Query count. The loader repairs instead when it already owes a repair, has work in flight, a replay is pending, or no cursor can express the end. Window moves: - A window move deferred behind a replay that a newer truncate discards now waits for every replay that holds publication and then applies. Before, it rejected with that replay's AbortError and an older move's window stayed. Oracles: - The ordered-work refetch law now allows the documented full-source refill of an unindexed plan whose bounded prefix leaves the window short. - The replay-refinement oracle keeps the discarded-replay trace; one older replay now checks the moved window instead of an AbortError. - Query DB's first-page witness requires exactly the end's tie request and an unchanged active Query count; the request-authority unproven-report law accepts the end's tie as the proof step. Co-authored-by: Isaac <no-reply@databricks.com>
Co-authored-by: Isaac <no-reply@databricks.com>
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Actionable comments posted: 2
- 🪄 Fix comments: Fix CodeRabbit comments on this PR
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Inline comments:
Review comments at @packages/db/src/query/live/ordered-source-loader.ts:
- Line 681: In revalidateLoadedCoverage, update the lastBoundary equality check
so it only treats the end value as an already-read tie when lastBoundary is
defined; preserve the existing Object.is comparison for defined boundaries.
Review comments at
@packages/db/tests/query/load-subset-replay-refinement-oracle.test.ts:
- Around line 2275-2277: Update the replay-case comment to state that the
deferred newer window move waits until replay releases publication and then
applies; do not imply that the discarded replay rejects it or that the older
move wins.
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.changeset/keep-live-query-through-failed-replay.mddocs/contributing/oracle-coverage.mdpackages/db/mangle-cache.jsonpackages/db/src/query/live/ARCHITECTURE.mdpackages/db/src/query/live/collection-config-builder.tspackages/db/src/query/live/ordered-source-loader.tspackages/db/tests/query/load-subset-replay-refinement-oracle.test.tspackages/db/tests/query/ordered-source-loader-state-oracle.test.tspackages/db/tests/query/ordered-work-oracle.property.test.tspackages/query-db-collection/tests/refetch-ordered-prefix-oracle.test.ts
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Address CodeRabbit review: an undefined order value at the page's end matched lastBoundary's no-tie sentinel, so a report was ignored without a proof. Also reword a named replay's comment to state the fixed behavior. Co-authored-by: Isaac <no-reply@databricks.com>
The request-authority unproven-report law judged the report's own pass, but pending joined work defers ordinary loading, so the owed repair or tie runs on the pass after that work finishes. test:dist found the case. The law now judges that later pass, and a named replay fails under the old law. Co-authored-by: Isaac <no-reply@databricks.com>
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- Around line 2980-2983: In the ordered-source loader state oracle, guard the
owedProof assertion and clearing so it runs only when truncatePending is false
and the loader is not disposed; preserve the obligation during replay so a later
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| if (owedProof) { | ||
| expectProofRequest(owedProof.from, owedProof.windowSize) | ||
| owedProof = undefined | ||
| repairedReportsOnOwnPage++ |
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🎯 Functional Correctness | 🟠 Major | ⚡ Quick win
🔎 Supported by static analysis
🏁 Script executed:
sed -n '2520,2585p' packages/db/tests/query/ordered-source-loader-state-oracle.test.ts
sed -n '2585,2635p' packages/db/tests/query/ordered-source-loader-state-oracle.test.ts
sed -n '2955,3060p' packages/db/tests/query/ordered-source-loader-state-oracle.test.ts
rg -n 'owedProof|settleReplay|test:oracles' packages/db/tests/query/ordered-source-loader-state-oracle.test.ts packages/db/package.jsonRepository: TanStack/db
Length of output: 13021
Defer the proof assertion during replay or after disposal.
truncate preserves owedProof, but replay does not issue requests until it settles. A disposed loader owes no further proof. The current check can therefore fail an allowed history and make test:oracles fail. settleReplay does not clear the obligation; a later joinedIdle can validate and clear it.
Suggested fix
- if (owedProof) {
+ if (owedProof && !truncatePending && !disposed) {📝 Committable suggestion
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| if (owedProof) { | |
| expectProofRequest(owedProof.from, owedProof.windowSize) | |
| owedProof = undefined | |
| repairedReportsOnOwnPage++ | |
| if (owedProof && !truncatePending && !disposed) { | |
| expectProofRequest(owedProof.from, owedProof.windowSize) | |
| owedProof = undefined | |
| repairedReportsOnOwnPage++ |
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Review comment at
@packages/db/tests/query/ordered-source-loader-state-oracle.test.ts around lines
2980 - 2983:
In the ordered-source loader state oracle, guard the owedProof assertion and
clearing so it runs only when truncatePending is false and the loader is not
disposed; preserve the obligation during replay so a later joinedIdle can
validate and clear it.
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… it owes Address CodeRabbit review: a truncate, disposal, failure, or move between a deferred unproven report and the pass after joined work can change or end what the report owes. Only quiet steps now keep the obligation; a named replay with a truncate failed under the old law. Co-authored-by: Isaac <no-reply@databricks.com>
… the ordered oracles - The ordered-work model now sorts undefined ranks with null ones, as the comparator does, and its histories generate both. A random campaign then found that its in-flight order check treated null and undefined as different ranks; nullish ranks now tie there too. - Peers over a refetching provider stay in the grammar for source filters (#2155 excludes only joined filters). A proven-report law requires that a report which changes nothing the first query's own page and end tie prove starts no request for it and leaves it owing no repair. A campaign fixed to that premise must reach it; a loader that repairs every report fails it. - A request-authority named replay reaches a staged end tie that pending joined work defers; a loader that drops the staged tie fails it. - The held fixed campaign moves to a seed that keeps its reach after the row generator changed. Co-authored-by: Isaac <no-reply@databricks.com>
…alidation An `undefined` page end matched the loader's no-tie value, and the guard kept that match from ignoring a report. No cursor expresses a nullish end, so the loader has started or will start a full-source read, which covers the window either way. A mutant without the guard survived every ordered oracle. Saves 18 B gzip in @tanstack/db. Co-authored-by: Isaac <no-reply@databricks.com>
Co-authored-by: Isaac <no-reply@databricks.com>
The replay refinement oracle's generated section excused the window
whenever a load failed, so only fixed tests judged that a failed replay
keeps the last publication, and one named replay pinned a demand that
fails while its replay is open. A retention law and a failed-replay
campaign now judge both.
- Law: ARCHITECTURE.md law 9 and "Replay participants and failure". A
truncate raises a publication barrier; every load its source starts
while it is up joins it; a participant's failure fails the replay while
its logical demand is held; while any barrier is up the query shows the
rows it showed when the first one rose. A participant counts as recovery
for the terminal-error law.
- Reach (createOracleReach, minimum 5, 200 histories each): judged failed
replay fixed 72 / random 78; judged held replay 75 / 79; demand started
after the commit failing while its replay loads 33 / 46; the include
form 18 / 22.
- RED: the branch's production files reverted to origin/main fail both
failed-replay campaigns (convergence: terminal error).
- GREEN: load-subset-replay-refinement-oracle.test.ts, 34 tests.
- Mutants: a failed replay that releases the publication gate fails both
failed-replay campaigns ("retained publication"); a subscriber that ends
the query when a demand fails while its replay still loads fails both
("convergence: terminal error").
- Model corrections found while building it, each from ARCHITECTURE.md: a
failure is scoped to its logical demand, so a retired failed demand and
its replacement publish; an ordered tie request is not lazy demand, which
had let a failed tie request excuse a terminal error.
- Limits: sources with two subscriptions in the query (a peer, or a query
that both joins and includes markers) are not judged; barriers that rise
before the first ready are not judged; a barrier where a release threw
during the replay's start is skipped.
Co-authored-by: Isaac <no-reply@databricks.com>
Two production repairs in this branch were killed only by named replays: the deferred window move that a discarded replay rejected, and the guard that keeps a failure before the first ready fatal. A preload-recovery campaign now generates both. - Law: ARCHITECTURE.md "Replay participants and failure" (a deferred move waits for every replay that holds publication and applies unless one failed) and the initial-readiness law (a failure before the first ready ends the query, so the preload settles). - Reach (createOracleReach, minimum 5, 300 histories each): lazy demand in a replay failing before the first ready, fixed 37 / random 32-40; a window move behind a replay a newer truncate discards, 41 / 39-49. - RED: the builder from 21fbd03 fails the fixed campaign ("settled window"); the builder without the initial-failure guard fails it ("initial preload settles"). The fixed seed kills both; each dies in about half of 200-run seeds. - GREEN: load-subset-replay-refinement-oracle.test.ts, 36 tests, three runs. - Model correction: a replay completes when its last participant's rows apply, so the retention model now settles a participant after its commit and lowers the barrier then. Demand that a deferred move starts afterwards no longer joins a finished replay. The gate-release and pending-replacement mutants still fail both failed-replay campaigns. - Limits: the random campaign kills each named mutant about half the time. Co-authored-by: Isaac <no-reply@databricks.com>
The unproven-report law was reached in about one broad-campaign history in 10,000, the proven-report random campaign counted no reach, and the refetch law's unindexed short-refill exception had no reach on either side. - Law: ARCHITECTURE.md ordered recovery. A report over a first page that no row the loader read proves starts a repair or reads the end's tie; a report the first page proves starts nothing; a signalling refetch's repair reads no full source except the refill of an unindexed plan whose bounded prefix leaves the window short. - Reach (createOracleReach): unproven-report campaign, 300 histories, minimum 20: fixed 104, random 84. Unindexed-refetch campaign, minimum 5: law applied fixed 16 / random 18, short refill excused 26 / 24. Proven-report random campaign: at least one history. - RED: main's loader fails both unproven-report campaigns. - GREEN: ordered-source-loader-state and ordered-work oracles, 354 tests. - Mutant: a loader that answers every report with a full-source read fails the unindexed-refetch fixed seed and random runs; about half of fixed seeds kill it, and this one does. - Limits: the unproven-report campaign starts every history with the same three commands; the fake's installed rows ignore a read's limit, so the first-page ignore branch stays with the ordered-work oracle. Co-authored-by: Isaac <no-reply@databricks.com>
… collection A query that joins and includes the same on-demand source has two subscriptions to it, each with its own truncate replay. A truncate's commit can retire one subscription's only demand privately; its emptied replay then closed while the other's still loaded, and demand the graph started for rows the commit exposed fell outside every replay. Its failure ended the query with error 228, the #2224 class through a second subscription. A subscription's replay now neither publishes nor closes as empty while a sibling subscription of the same collection in the graph still has replay work, so demand started meanwhile joins it. - Law: ARCHITECTURE.md "Replay participants and failure", revised here: a live query's subscriptions to one collection share one publication barrier. The replay oracle's participant rule and retention law now apply to them (previously skipped as unattributable). - Reach (createOracleReach, minimum 5): a sibling-demand branch of the failed-replay campaign declares a demand that fails inside the shared barrier of a query that joins and includes markers. - RED: the parent commit's production code fails the named replay "a demand that fails while a sibling subscription's replay still loads" and both failed-replay campaigns at "convergence: terminal error". - GREEN: replay refinement oracle 37 tests; @tanstack/db 285 files / 13,816 tests; test:dist 323; query-db 42 files. - Mutants: removing the hold at replay completion, or the hold for an emptied replay, each fails the named replay and both campaigns. - Size: +175 B gzip in @tanstack/db (+276 to +451). - Limits: histories with a peer query stay unjudged by the retention law. Co-authored-by: Isaac <no-reply@databricks.com>
Co-authored-by: Isaac <no-reply@databricks.com>
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A lazy join or include load can fail while a source truncate replays. That failure no longer ends the live query. The truncate replay fails instead. The query keeps its last public snapshot until a later truncate replay of that source succeeds. A failure before the query first becomes ready still ends the query.
The random campaign of the replay-refinement oracle found this case. The oracle's own model also judged it wrongly, so this PR changes both.
The failure in #2224
The shrunk history is three commands over an ordered window of one row:
The window shows row 2, the only unmarked row. These steps followed:
{2}to{1}.SubsetDemandController.setDemandreleased the{2}segment before it started{1}.{2}was the include subscription's last logical demand. Its retirement ended that subscription's truncate replay (retireEmptyReplay).{1}acquisition attempt therefore started outside any replay.{1}load failed.collection-subscriber.tscalledfailDemand, and the query entered terminal error 228.The
{1}demand existed only in the private replacement. After the marker replay succeeds, row 1 has its marker again and the window returns to row 2. A transient private state ended the query permanently.The law
ARCHITECTURE.md law 9 says that a failed truncate replay keeps the prior public result until a later authoritative replay succeeds. The section "Replay participants and failure" says that every acquisition started while a replay is active belongs to its barrier. This PR adds a paragraph to that section with these rules:
loadSubsetthrow also ends it, because it rolls its logical owner back.Production changes
All changes are in
@tanstack/db:subset-demand-controller.tsstarts new coverage before it releases retired coverage. A demand change no longer empties its subscription's demand and ends its replay.collection-subscriber.tsandcollection-config-builder.tskeep a demand failure non-fatal when it fails the subscription's replay.failDemandstays fatal while the live query is stillloading.subscription.tsopens a replay at every truncate for a query subscription that acquires. Without demand, that replay starts no recovery work and keeps the subscription statusready.subset-demand-controller.tstreats a rejected aborted request as obsolete demand. The truncate replay decides a superseded acquisition, even when the replay settled first.The last change also prevents two failures that already occur on
main. A source that rejects an aborted request withAbortError, as the source contract asks, ended the query with error 228 in two cases:The oracle's old fake source resolved aborted requests, so it never reached either case.
The oracle defect
The ordered section of
load-subset-replay-refinement-oracle.test.tsdecided if a failed load was fatal. It read a flag that the driver set only during the synchronousmarkerSync.commit(). A subscription starts its replay loads in a later microtask, so the model mislabeled loads in two directions:errorafter any failed replay load. The check was weaker than its prose said.The model now uses this rule (
belongsToRecovery). A load belongs to a truncate's recovery when one of these is true:whereobject is the same. ARCHITECTURE.md now states this.A
replayLoadsreach witness requires the campaigns to reach replay loads. If production rebuilt the request data for a replay, this witness fails.Bug-class closure
The declared class is "a lazy demand failure that belongs to a truncate recovery ends the live query".
The history grammar now also has these elements:
AbortError.settlecommands that keep later loads held or settle the newest held load.The production path has three parts:
The oracle compares these public observations once loading is quiet:
ordered-lifecycle-oracle.property.test.tsowns a new truncate-work witness. A zero-limit window issues no request and reports no loading at a truncate. A one-row window must reacquire.1817832416, path115:1:2:2:2convergence: terminal erroronmainconvergence: terminal errorinitial preload settles: expected false to be truewherereplayLoads: expected 0 to be greater than 0in both campaigns466044415and three moreSubset demand failed: marker load abortedonmainrecovery failure ends the query: expected 1 to be +0The oracle keeps every trace that a campaign found as a named replay.
Limits
whereshape. Production also keeps demand non-fatal when it starts after the commit while its replay is still open. One named replay pins that case, and the coverage map records the gap.A related ordered-window defect
The ordered-work oracle's random campaign found a defect on
mainin the same lazy-demand path, with seed-1160947149. A signalling refetch re-runs each served request alone and then reports that pages may have shifted. In the trace, the refetch moved the first page's end earlier, from rank 2 to rank 0. Row 11 also has rank 0, but no answer held it.The loader ignored the report because its window was inside its own first page. The rule takes the next installed row as proof that the next source row sorts after the page's end. That row was row 1 (rank 2), installed only by the tie request for the old end. A later window move then read local rows and skipped row 11.
The loader now accepts an installed row past the page as proof in two cases only:
When the end moved, the loader reads only the new end's tie on the next pass. The refetched page holds every row before the end, so that tie completes the proof without a repair. The loader then releases the older tie, whose rows sort after the end and outside the window. It does not treat the deletes from that release as an order change. ARCHITECTURE.md states the rule.
The loader repairs instead in these cases:
Query DB's ordinary top-N insert moves the page's end. With this rule it sends the refetched Queries plus one tie request, and its count of active Queries stays the same. Query DB's first-page witness now requires exactly that.
main-1160947149and its named replayrows after step 4: expected [ null, +0, 2 ] to deeply equal [ null, +0, +0 ]unproven report: ... issued no repairexpected 3 to be 2(active Queries)The request-authority oracle had an ignored-report law that required the old, unsound behavior. Its fake ignores a read's limit, so it could not tell a page row from a row that another request installed. The law now uses the narrowed premise, and a new unproven-report law requires the repair.
A window move behind a discarded replay
The replay-refinement oracle now starts some histories during the initial preload. Seed
-1087619433then found a defect onmain. A window move waited behind a marker replay. A source truncate discarded that replay, and its completion rejected withAbortError. The waiting move rejected with it, so an older move's window stayed.ARCHITECTURE.md says that a move started during a replay waits for it and applies after the replacement completes. A discarded replay did not fail. The deferred move now waits for every replay that still holds publication, and then applies. A failed replay or a cleanup still rejects it. A named replay fails without the change.
One older named replay required that move to reject with
AbortError. The contract does not promise that, so the replay now checks the moved window.An oracle law that was too strict
The ordered-work refetch law required no full-source read after a signalling refetch. ARCHITECTURE.md allows one for an unindexed plan: "an underfilled unindexed prefix retains the established full-source fallback". Seeds
-81515317and583212354reached that case onmain. The law now allows the read only when the model's bounded prefix leaves the window short. A mutant that repairs every report through the full source still fails the pinned-seed campaigns.Oracle coverage added with these repairs
undefinedranks withnullones, as the comparator does, and its histories generate both.Code weight
pnpm size:comparereports@tanstack/dbat +276 B gzip and +317 B brotli, and theappscenario at +271 B gzip. The tie-only path for a moved end is the largest part, at +891 minified bytes inordered-source-loader.js. A bounded repair for that case would cost less code, but it sends about two more requests on each top-N insert in Query DB. The window-move loop adds 175 minified bytes. The obsolete-rejection rule and the guards for the first ready and for a replay without demand are the rest. Reordering the controller saved 44 B. No existing branch became redundant. I deleted two guards that mutants showed to be equivalent. One kept anundefinedpage end from matching the loader's "no tie" value. A nullish end always causes a full-source read, so that match changes nothing.Tests, ARCHITECTURE.md, and the coverage map grow separately.
Verification
The
@tanstack/dbsuite passes.The query-db, electric, react, powersync, and trailbase suites pass.
Ten random replay-refinement campaigns at three times the default budget pass.
tscand ESLint pass.Ten random rounds of the replay-refinement, ordered-work, and request-authority oracles at three times the default budget pass.
Closes #2224
This pull request and its description were written by Isaac.