Timeline

zig build test was 9m13s, and the tests it actually ran were a small fraction of that: it also compiled the e2e and smoke harnesses in the pinned ReleaseSafe and then never executed them. test is now unit tests only -- 2m54s cold, 1m42s warm -- and the new gate step carries those two compile proofs.

The dst, bench and smoke UNIT tests deliberately stay on test. They are unit tests despite their siblings' names, zig build dst/smoke run the simulation and the interop check rather than them, and CI invokes the lanes one by one and never invokes gate -- so moving them would have dropped them from CI while every step still looked green. ci_test's declared_steps records gate as intentionally not-in-CI, and names that failure mode for the next lane someone adds. check-in: 7363238ad5 user: dmestas tags: trunk

The incremental tree editor diverged from buildTree on realistic filename distributions. OldTreeCursor.appendPrefixAtHeight read the retained native-prefix list without consuming it, so one descriptor could be spliced into two different output levels: buildUnpublished placed the height-1 prefixes into the leaves, and mergeRootPrefixes then prepended the identical descriptor again before finishRootLevel. The emitted interior node carried the same S key twice, which fails artifact.parse's ascending-S guard, so an import aborted partway through a real history with a SyntaxError raised by our own grammar.

finishCheckpoint already guarded its own splice with a height test. That guard was an ad-hoc workaround for this same double-append, and mergeRootPrefixes never had one. The splice now consumes what it emits, so a retained descriptor lands in exactly one level and the guard becomes unnecessary rather than duplicated.

Found by importing marktext, not by the suite. Every name corpus here was uniform, and a duplicated prefix descriptor requires names that share prefixes at differing depths, so 55 tests could pass over a defect that breaks real repositories. The new seeded differential sweep generates four corpora of 136 to 240 paths with mixed depth, shared directories, dotfiles and 1 to 43 byte basenames, over every supported k with twelve batches each, and asserts it reached a tree at least three levels deep so it cannot quietly degrade into testing flat roots. It diverges in 20 of 452 batches against the unfixed editor, every divergence unparseable.

The decoded-root validation memo lands alongside it: repeated lookupTree validation against an unchanged root is answered once instead of rebuilt, which takes this file's own 56 tests from 1701 to 450 seconds over identical assertions. check-in: 4a95e436af user: dmestas tags: sub-manifest

Limits.max_file_commands_per_commit was a standalone number, and the caller pinned it to the width of our own benchmark corpus. That is a fixture size promoted to policy: no headroom, no way to raise it without a rebuild, and it refused legitimate histories. `git fast-export` lists an entire tree for a root commit and for any commit whose first parent was not exported, so the ceiling is reached by ordinary repositories whose initial commit lands a whole codebase at once.

The bound itself is necessary. admitData is the parser's only byte admission and it sees the byte count in a `data` header alone; every file command additionally allocates a list slot and a duplicated path into the per- commit arena with nothing charging for them, so the command loop is otherwise unbounded against a subprocess pipe.

It is now computed: fileCommandCeiling(limits) = max_total_data divided by min_retained_bytes_per_file_command, where that constant is @sizeOf(FileCommand) plus one -- a command's list slot plus the shortest path it can carry, the empty path being rejected. Nothing smaller is representable, which is what makes it safe to divide a byte budget by. The ceiling restates the arena authorization the caller already granted, in commands rather than bytes, and moves when that authorization moves.

Refusal retains the observed count, the ceiling, and the budget that produced it, so the diagnostic names all three rather than only its own error. The remaining limits gain distinct names -- Data, Event, FileCommand, Line, Merge and Path -- in place of one LimitExceeded that could not say which bound was hit. Exact-count data may carry an optional trailing LF, so only the first following empty line is ambiguous with the commit terminator; readDataExact and readCommitData split that decision instead of guessing. check-in: 85d510d361 user: dmestas tags: sub-manifest

Names beginning with `sym-` are ambiguous in this repository. A user tag written `sym-x` is stored under the canonical spelling `sym-sym-x`, so resolving `sym-x` correctly looks for `sym-sym-x`. An imported repository, though, can carry a tag whose stored canonical spelling already begins with `sym-`, and nothing could address it: the ordinary lookup rewrote the name and missed the artifact that was actually there.

Resolution now attempts the ordinary user-tag path first and consults the stored spelling only when that fails. The precedence is deliberate. A user tag continues to win over an imported canonical name, so no existing repository changes meaning, and the fallback is reachable only where the ordinary answer does not exist at all. check-in: fc9bcb81bd user: dmestas tags: sub-manifest

Callers publishing several artifacts together had only putArtifact, one at a time, so a failure partway left the store holding a prefix of the set with nothing naming what was missing. Each caller that cared wrote its own compensation, or quietly did not.

putArtifactBatch takes the whole set and appends it under a single transaction: either every item is durable or the store is byte-identical to its prior state. ArtifactBatchItem carries the hash, the bytes, and an optional delta base, so a batch may mix full and delta-encoded members without the caller resolving storage order first.

Nothing calls it yet. The importer, which needs a check-in's blobs to arrive as a unit or not at all, is the first caller and lands later on this branch. check-in: 7cf522fa5b user: dmestas tags: sub-manifest

Two layers decided independently what a reserved path is. update carried its own validateWorktreePath — an absolute/backslash/dot-dot check plus a hand-rolled case-insensitive comparison against the .zit family — while extras carried isControlName, which tested only the first /-delimited component of a path. They agreed by coincidence rather than construction, and the extras form admitted `.zit-managed/entries` because it asked about the component instead of the root.

control_paths now owns both questions. validateWorktreePath and isReservedRoot are the single definitions; update delegates to the first and extras to the second. isControlName takes the full root-relative key that add and move already hand it, so a path rooted in a control entry is refused at any depth rather than only at depth zero. firstComponent goes with its last caller.

The update test that pinned the old list is now a case table naming what is reserved and what merely resembles it, including the case-insensitive spellings the previous ad-hoc comparison happened to get right. check-in: 581db6e5ba user: dmestas tags: sub-manifest

A check-in's F card can name a symlink (§4.7.6-m5), but update refused one outright with error.SymlinkUnsupported, so any history carrying such a card could not be checked out, reverted, or updated to. The refusal was cheap to write and wrong: the reader already represents the entry, and only the worktree side lacked a branch for it.

materializeEntry and writePayload now create the link from the card's target bytes instead of writing a regular file containing them, and isCurrentState compares against .sym_link and the recorded target rather than the size and mode of a file that is not there. The managed-set walks accept .sym_link beside .file, so a materialized link reads as a tracked entry instead of an intruder the admission check rejects.

`zit revert` on a symlink card previously exited 1 naming the refusal. It now restores the entry, and the test reads the link back with readLink, which distinguishes native materialization from a regular file that merely holds the target's bytes. check-in: bb96853a0f user: dmestas tags: sub-manifest

The e2e root is one test binary holding every scenario, and its runner took no filter, so narrowing to a single scenario meant editing build.zig or paying for the whole root. `zig build e2e -- --test-filter NAME` now compiles the filter into the test artifact, accepting both the two-argument and the `--test-filter=NAME` spellings and passing nothing through when the arguments do not name a filter. check-in: cd70f19286 user: dmestas tags: sub-manifest

std.debug.assert is right for an internal invariant and wrong for a rule about data the function did not produce, and it is wrong in two different ways. Under the ReleaseSafe default it survives and PANICS: on the write path that is the trade we want, a crash over a durable bad frame, but on a peer-reachable path it is a remote denial of service. Under an explicitly chosen --release=fast it compiles to nothing and the input flows through unvalidated. One fix, a checked error, closes both.

Flags an assert only when all of: the fn is pub, returns an error union so a rejection was already available, the assert names one of its own parameters, and no earlier return in the body already rejects on that parameter. That last rule is what makes it signal -- delta.applyCopy returns MalformedDelta and then asserts to restate it, which is the CORRECT shape and must not be flagged.

The baseline is keyed on file, function and COUNT, never on line numbers: line numbers churn on every edit above them, while a count still catches a second bad assert added to a function that already has one. It fails in both directions, so a fixed finding must be removed from the list and the list can only shrink.

Existing findings are recorded, not fixed. Triage belongs in issue 19, where the ReleaseSafe default already reduces the write-path subset to crash-instead-of-corrupt and leaves the sync-side ones as the live exposure. check-in: 949e2b5542 user: dmestas tags: trunk

src/ carries 1086 std.debug.assert calls. They are how a detected inconsistency becomes a crash instead of a durable write -- TigerStyle's 'downgrade catastrophic correctness bugs into liveness bugs' -- and that trade exists only while the assertion does. ReleaseFast and ReleaseSmall compile every one to nothing, so a binary built that way converts each guarded corruption into an unguarded one, in a store where a bad frame is permanent and a crash is not.

Measured, not assumed. Read-side verbs are indistinguishable between the two modes: status, log and stat all sit inside noise on a 5 MB store. zit pack is not: 599ms fast against 15.2s safe, about 25x, because the delta encoder's best-of-N search is a tight per-byte loop where a bounds check is a large share of the work. That argues for setRuntimeSafety(false) on that measured loop -- local, reviewable, over code the fuzz and DST lanes already cover -- rather than stripping assertions from every other path in the binary. Not taken here.

Note the option surface changes: stating a preference replaces the -Doptimize enum with a -Drelease bool, so the deliberate escape hatch is the top-level --release=fast. -Doptimize=ReleaseFast no longer parses.

ci_test pins the preference, and says that if the project ever decides to ship unchecked, the pin should be deleted in that same commit so the decision is visible in history rather than arriving as drift. check-in: 4379187a10 user: dmestas tags: trunk