| Comment: | repostate: break same-mtime resolution ties by DAG ancestry, not hash order
Three commits made inside the same second made `zit` return the WRONG file content for `tip` and `trunk`, and made the binary contradict itself: `zit info tip` reported "leaf: no" while `zit leaves` named the same check-in a leaf. `zit cat f.txt tip` returned the ROOT's content and `zit cat f.txt trunk` returned the MIDDLE's, on a three-commit chain whose newest content was `v3`. A version-control system that silently hands back an old revision under a name that means "newest" is disqualifying, so this lands before anything else. WHAT WAS WRONG — three independent tie sites, not one The originally-recorded diagnosis blamed a single lexicographic artifact-hash tiebreak in `mergeBaseOf`. That was wrong for the reported symptom: the RED-proof gate built the equal-mtime chain in BOTH hash orderings and observed IDENTICAL failures, which rules out hash order as the mechanism. Fixing only that line would have left `cat tip` and `cat trunk` still returning wrong answers. The real picture: - `tipForm` — `mtime > best_mtime`, a strict `>` with no tiebreak at all, so the first entry in `events` INSERTION order won. Symptom: `tip` -> ROOT. - `resolveName` — ties settled by `tagxref` hash-map ITERATION order. Symptom: `trunk` -> MID. - `mergeBaseOf` — lexicographic artifact hash. A genuine defect, proven RED at unit level, but not the cause of the tip/trunk symptom and unreachable from the e2e merge path. WHAT CHANGED Equal-`event.mtime` ties are now settled by DAG ancestry: a descendant beats its ancestor. Genuinely concurrent nodes — same mtime, no ancestry relation — keep a deterministic least-artifact-hash fallback, documented at each site; hash order between UNRELATED leaves was never the bug. The shared helper (`MtimeMaxPick`) is used by `tipForm`, `resolveName`, `openLeafOf` and `dateResolve`, so every symbolic-name surface settles ties one way. Timeline ordering gets a second pass that re-orders each equal-mtime RUN descendants-first, deliberately overriding the hash tiebreak. It is a per-run repeated-maximal-element extraction, NOT a sort predicate: "descends-from, else hash" is not a strict weak order, and handing it to `std.mem.sort` would be undefined behavior. Runs are bounded by the check-ins sharing one millisecond. Settling a tie by ancestry allocates, so `resolveName`/`resolve`/`openLeafOf` gained `OutOfMemory`. Every caller switches it as an ABORT, never as a mismatch or "already correct" verdict — reporting an allocation failure as the exit-0 up-to-date message is exactly the lie those switches exist to prevent. `repository_test`'s closed-error-set assertion moved 2 -> 3 for that reason: it encoded the pre-fix set, not an inconvenient expectation. Two ride-alongs on the same resolution surface: - SF1 — `zit update trunk` used to fail as "invalid check-in ID": update accepted ONLY canonical 40/64-hex. Its argument is a check-in name like every other verb's, so it now runs the shared 8.3 procedure. A canonical ID still short-circuits, leaving update's cold path byte-for-byte as it was. - SF5 — a `tip` that names a non-leaf is now an in-binary assertion, not just a test. It is legitimate ONLY under a non-monotone clock (a child stamped strictly earlier than its parent); a child that TIES its parent means the ancestry tiebreak failed to fire, which is the defect itself. This tripwire would have caught the original bug. RED PROOF (recorded by the RED-proof gate, 2026-07-19; per BLOCKER-FIX-PLAN.md section 2, no product code changed until RED was proven) Unit, `src/repostate_test.zig`, deterministic equal-mtime chains built directly in BOTH hash orderings — no wall-clock dependence: repostate REGRESSION B1: tip resolves to the descendant on an equal-mtime chain (head has the greatest hash) repostate REGRESSION B1: tip resolves to the descendant on an equal-mtime chain (head has the least hash) repostate REGRESSION B1: resolveName picks the descendant on an equal-mtime chain (head has the greatest hash) repostate REGRESSION B1: resolveName picks the descendant on an equal-mtime chain (head has the least hash) repostate REGRESSION B1: tip and resolveName agree with the leaf set in both hash orderings repostate REGRESSION B1: mergeBaseOf picks the deepest common ancestor when every candidate shares an mtime [failed pre-fix: expected 2, found 1] End-to-end, `src/e2e.zig`, same-second commits with NO sleep between them — same-second IS the point: cli REGRESSION B1: same-second commits resolve tip and trunk to the newest check-in cli REGRESSION B1 (SF1): update accepts a symbolic name and lands on the newest check-in cli REGRESSION B1: open materializes the newest same-second check-in into a fresh clone cli REGRESSION B1: a same-second two-branch merge picks the correct base and is never up to date All of the above failed against pre-fix trunk; the two hash-ordering pairs failed IDENTICALLY, which is the evidence that retired the hash-order theory. TEST EVIDENCE NOW In this worktree at the committed tree: `zig fmt --check .`, `zig build`, and `zig build test` each exit 0 — full battery, no filtering. The only pre-existing expectation changed is the `repository_test` error-set count noted above, and it changed because it encoded the old set. Markers `// REGRESSION B1:` are stable so state probes can grep trunk for them. No borrowed technique: the ancestry tiebreak and the per-run topological micro-ordering are original to this change. |
|---|---|
| Timelines: | family | ancestors | descendants | both | blockers |
| Files: | files | file ages | folders |
| SHA3-256: |
bdb49cc5ca43a6417de28de5fb026f2c |
| User & Date: | dmestas on 2026-07-19 11:56:16.100 |
| Other Links: | branch diff | manifest | tags |
|
2026-07-19
| ||
| 15:07 |
add/addremove/commit: refuse symlinks consistently (blocker B3)
A symlink anywhere in the checkout permanently wedged `commit`. `extras.zig` classifies a symlink as an extra (B-extras-9), and the recursive `add DIR` / `addremove` paths reuse that sweep as their add set without re-applying the kind test that explicit `zit add sym.txt` and `commit` both apply. The recursive path therefore TRACKED exactly what the direct path REFUSED: after `zit add .`, every subsequent `zit commit` died with "cannot commit 'sym.txt': not a regular file", `zit status` called an on-disk file missing, and the only way out (`zit rm sym.txt`) was named nowhere. `add .` is the documented whole-tree workflow, so any repo containing a symlink was stuck. WHAT CHANGED Consistent refusal: 0.1.0 does not version symlinks, on every path. 1. `extras.Extras` entries widen from a bare path to `Entry{path, is_symlink}`. The sweep already lstat-classified every entry (`resolveKind`); the verdict now rides out on the entry instead of being re-derived by callers. That is the point of the shape: `add` and `addremove` do NOT re-stat swept items, so the two paths cannot drift from the deep module's classification again — which is the mechanism of this bug. Ordering is unchanged (sort is by `path`; `is_symlink` never participates), and every postcondition assert is preserved. 2. The five `items()` consumers split by role. `extras` and `clean` ignore the tag — enumerating verbs do not judge, and a symlink stays a listable, deletable extra. `add`'s directory sweep and `addremove`'s insert loop filter on it. 3. `classifyPath`'s catch-all `else => .not_regular` splits: `.sym_link` gets its own `Outcome` and the wording `symlink (not versioned in 0.1.0)`; a fifo/socket/device keeps "not a regular file". Those are not the same refusal and must not read as one. The wording is one shared const so the explicit refusal and the recursive skip notice cannot diverge. 4. `commit`'s `Capture.not_regular` carries whether the entry was a symlink, and `commitNotRegular` renders the recovery for that case: "run 'zit rm PATH' to stop tracking it". This is how repos already wedged by a pre-fix `add .` get out; there is no migration code and none is needed. REPORTING DECISION (stated, not implied) `add` prints each skip to stderr, alongside its existing already-tracked notice: add's contract is per-argument feedback. `addremove` withholds symlinks SILENTLY. Its report is a two-channel ADDED/REMOVED ledger of state transitions, and a skipped symlink is a non-transition; growing a third notice channel there would change the shape of a report other tooling reads. `zit extras` is the verb that shows the symlink is still present and untracked. `status` needed no change: post-fix the symlink is simply untracked. TESTS Five e2e regressions, marker `// REGRESSION B3:`: the breakdown doc's repro chain verbatim (init/add ./commit/status/extras); an `addremove` variant with symlinks sorting BOTH before and after the regular file the sweep also yields, so a filter that latched off the previous item's kind fails one of the two; explicit `add sym.txt` refusing with the symlink wording and tracking nothing; the wedge-recovery chain (pre-tracked symlink -> commit names `zit rm` -> rm -> commit succeeds -> status clean); and a `clean --dry-run` contract-partner guard that was green before the fix and stays green through it, proving clean still lists a symlink as an extra after the `Extras` type change. A unit assertion in `extras.zig` pins the tag itself, and `commitNotRegular`'s renderer test covers both branches. Two pre-existing e2e expectations changed, both because they encoded the bug or its wording: - `cli addremove B-addremove-2` asserted the ADDED set was byte-identical to `zit extras`, symlink included. That identity IS the defect. It now asserts the add set is the extras set MINUS symlinks, and additionally that the symlink remains an extra. - `cli add B-add-5` asserted the fifo-generic wording for a named symlink. It now asserts the symlink-specific wording. Four `commit` invocations inside the new B3 tests use `runCommitEnv` with an explicit user rather than bare `runZit`; the isolated e2e environment has no resolvable author, which is a harness requirement, not a behavior change. TEST EVIDENCE In this worktree at the committed tree: `zig fmt --check .`, `zig build`, `zig build test`, `zig build e2e` (417 tests) and `zig build dst` each exit 0 — full battery, no filtering. Pre-fix the four B3 repro tests failed and the `clean --dry-run` guard passed, as designed. No borrowed technique: the entry-tag shape is original to this change. No performance claim is made. check-in: 1aeb531cac user: dmestas tags: blockers | |
| 14:32 |
Merge blockers: resolve same-mtime ties by DAG ancestry (B1/B2)
Three commits inside one second made 'zit cat f.txt tip' return the root's content and 'trunk' the middle's, while 'zit leaves' named the newest — the binary contradicting itself, exit 0, no warning. The diagnosis that opened the campaign was wrong and is worth recording: it blamed a single lexicographic-hash tiebreak in mergeBaseOf. Building the equal-mtime chain in BOTH hash orderings produced identical failures, which ruled hash order out as the mechanism. There were three independent tie sites — tipForm settled on events insertion order, resolveName on tagxref iteration order, mergeBaseOf on artifact hash. A fix confined to the originally-blamed line would have left tip and trunk still wrong. Equal event.mtime is now settled by ancestry: a descendant beats its ancestor. Genuinely concurrent nodes keep a deterministic least-hash fallback — hash order between unrelated leaves was never the defect. Timeline gets a second pass re-ordering equal-mtime runs descendants-first. Ride-alongs on the same surface: 'update' accepts symbolic names (SF1), and a 'tip' naming a non-leaf is now an in-binary assertion (SF5) — the tripwire that would have caught this originally. Merged tree re-verified on trunk: fmt, build, test, e2e, dst 6x1000 all green. Remote CI is unavailable (self-hosted runner offline); the local battery is the gate per operator direction. check-in: bc7b914316 user: dmestas tags: trunk | |
| 11:56 |
repostate: break same-mtime resolution ties by DAG ancestry, not hash order
Three commits made inside the same second made `zit` return the WRONG file content for `tip` and `trunk`, and made the binary contradict itself: `zit info tip` reported "leaf: no" while `zit leaves` named the same check-in a leaf. `zit cat f.txt tip` returned the ROOT's content and `zit cat f.txt trunk` returned the MIDDLE's, on a three-commit chain whose newest content was `v3`. A version-control system that silently hands back an old revision under a name that means "newest" is disqualifying, so this lands before anything else. WHAT WAS WRONG — three independent tie sites, not one The originally-recorded diagnosis blamed a single lexicographic artifact-hash tiebreak in `mergeBaseOf`. That was wrong for the reported symptom: the RED-proof gate built the equal-mtime chain in BOTH hash orderings and observed IDENTICAL failures, which rules out hash order as the mechanism. Fixing only that line would have left `cat tip` and `cat trunk` still returning wrong answers. The real picture: - `tipForm` — `mtime > best_mtime`, a strict `>` with no tiebreak at all, so the first entry in `events` INSERTION order won. Symptom: `tip` -> ROOT. - `resolveName` — ties settled by `tagxref` hash-map ITERATION order. Symptom: `trunk` -> MID. - `mergeBaseOf` — lexicographic artifact hash. A genuine defect, proven RED at unit level, but not the cause of the tip/trunk symptom and unreachable from the e2e merge path. WHAT CHANGED Equal-`event.mtime` ties are now settled by DAG ancestry: a descendant beats its ancestor. Genuinely concurrent nodes — same mtime, no ancestry relation — keep a deterministic least-artifact-hash fallback, documented at each site; hash order between UNRELATED leaves was never the bug. The shared helper (`MtimeMaxPick`) is used by `tipForm`, `resolveName`, `openLeafOf` and `dateResolve`, so every symbolic-name surface settles ties one way. Timeline ordering gets a second pass that re-orders each equal-mtime RUN descendants-first, deliberately overriding the hash tiebreak. It is a per-run repeated-maximal-element extraction, NOT a sort predicate: "descends-from, else hash" is not a strict weak order, and handing it to `std.mem.sort` would be undefined behavior. Runs are bounded by the check-ins sharing one millisecond. Settling a tie by ancestry allocates, so `resolveName`/`resolve`/`openLeafOf` gained `OutOfMemory`. Every caller switches it as an ABORT, never as a mismatch or "already correct" verdict — reporting an allocation failure as the exit-0 up-to-date message is exactly the lie those switches exist to prevent. `repository_test`'s closed-error-set assertion moved 2 -> 3 for that reason: it encoded the pre-fix set, not an inconvenient expectation. Two ride-alongs on the same resolution surface: - SF1 — `zit update trunk` used to fail as "invalid check-in ID": update accepted ONLY canonical 40/64-hex. Its argument is a check-in name like every other verb's, so it now runs the shared 8.3 procedure. A canonical ID still short-circuits, leaving update's cold path byte-for-byte as it was. - SF5 — a `tip` that names a non-leaf is now an in-binary assertion, not just a test. It is legitimate ONLY under a non-monotone clock (a child stamped strictly earlier than its parent); a child that TIES its parent means the ancestry tiebreak failed to fire, which is the defect itself. This tripwire would have caught the original bug. RED PROOF (recorded by the RED-proof gate, 2026-07-19; per BLOCKER-FIX-PLAN.md section 2, no product code changed until RED was proven) Unit, `src/repostate_test.zig`, deterministic equal-mtime chains built directly in BOTH hash orderings — no wall-clock dependence: repostate REGRESSION B1: tip resolves to the descendant on an equal-mtime chain (head has the greatest hash) repostate REGRESSION B1: tip resolves to the descendant on an equal-mtime chain (head has the least hash) repostate REGRESSION B1: resolveName picks the descendant on an equal-mtime chain (head has the greatest hash) repostate REGRESSION B1: resolveName picks the descendant on an equal-mtime chain (head has the least hash) repostate REGRESSION B1: tip and resolveName agree with the leaf set in both hash orderings repostate REGRESSION B1: mergeBaseOf picks the deepest common ancestor when every candidate shares an mtime [failed pre-fix: expected 2, found 1] End-to-end, `src/e2e.zig`, same-second commits with NO sleep between them — same-second IS the point: cli REGRESSION B1: same-second commits resolve tip and trunk to the newest check-in cli REGRESSION B1 (SF1): update accepts a symbolic name and lands on the newest check-in cli REGRESSION B1: open materializes the newest same-second check-in into a fresh clone cli REGRESSION B1: a same-second two-branch merge picks the correct base and is never up to date All of the above failed against pre-fix trunk; the two hash-ordering pairs failed IDENTICALLY, which is the evidence that retired the hash-order theory. TEST EVIDENCE NOW In this worktree at the committed tree: `zig fmt --check .`, `zig build`, and `zig build test` each exit 0 — full battery, no filtering. The only pre-existing expectation changed is the `repository_test` error-set count noted above, and it changed because it encoded the old set. Markers `// REGRESSION B1:` are stable so state probes can grep trunk for them. No borrowed technique: the ancestry tiebreak and the per-run topological micro-ordering are original to this change. check-in: bdb49cc5ca user: dmestas tags: blockers | |
| 01:58 |
Merge release-0.1: merge3_properties algebraic-property fuzz (P4-F7)
Lands the last of the seven 0.1.0 release blockers. merge3 — the three-way merge — had no fuzz target, and silent merge corruption is the worst failure a version-control system can have, because it produces a tree that looks right. The merged tree was re-verified on trunk after the merge, not inherited from the branch: zig fmt --check ., zig build, and zig build test all exit 0. The merge reported no conflicts and touched four files; fossil extras is empty, so nothing referenced went unadded. The conflict-marker sequences a repo-wide grep reports in src/merge3.zig and src/e2e.zig are that module's own sentinel constants and the tests asserting on them, not merge residue. Landed by hand rather than by the release workflow: its TigerStyle gate spent its three-round budget on this diff and halted without a confirming pass. The final round's two blockers were real — a zig fmt failure and an oracle hole where conflict spans were validated individually but never as ordered and disjoint, which would have let one widened span exempt every line from oracle 4 — and both were fixed by the round that followed. Verified here before landing: fmt clean, the ordered/closes_once checks present, and merge3_properties running clean at seed 1 over 2000 rounds. check-in: 08e7c6d6f1 user: dmestas tags: trunk | |