Timeline

Assert density was collapsing exactly where the working tree and the wire are touched: update.zig held 2 asserts across 2127 lines, serve.zig 3, transport.zig 2 -- against the hundreds in the artifact and sync cores. This pass adds 17 asserts stating invariants that already hold: the checkout-state transitions in update (managed-set, record and rollback image agreement around each applyCheckin stage), the request/response postconditions in serve (media, arity and body-ceiling), and the frame, redirect and body-cap postconditions in transport. Asserts only, no behaviour change; where a result had to be named to assert on it the error mapping is preserved exactly. All survive the deterministic simulation sweeps, which is the point of landing them before the checkout crash-recovery sweep that will hammer update. check-in: 9654d06838 user: dmestas tags: trunk

Raise assert density in the three thinnest library modules, enforcing invariants that already hold. Asserts only, no behavior change.

update.zig: guard the checkout-state transition. applyCheckin asserts the desired managed set equals the target plan membership (validateTopology proves the paths unique); requireClean asserts a clean tree's plan membership equals the recorded managed set; recordUndoImage asserts the affected union covers both operands; commitMaterialization self-guards that the committed record names exactly the staged check-in and that the managed set is its membership; the merge path asserts one rollback pre-image per path and a shared pre-merge managed baseline.

serve.zig: a servable request is a POST bearing a request-valid compressed media type (§4 L759-764); an accepted body honors the §4 L1148-1149 ceiling; a compressed reply is application/x-fossil (§4.1); the accept loop honors its request bound.

transport.zig: a framed container carries its 4-byte length prefix (§4.1); an unframed reply stays within reply_body_cap (§4 r9); a followed redirect lands only on an http/https transport (§4 r12/r13). closed check-in: c9fb87f554 user: dmestas tags: h5a-asserts

Fourth and final family extraction. A pure behaviour-preserving move: the mutating checkout verbs -- update, bisect, merge, revert, undo, redo, commit, amend -- and the helpers private to them (the undo journal, the dirty-tree gate, the checkout record, the commit and amend manifest assembly) move verbatim into src/cmd/checkout.zig, byte-identical to their source but for the pub the dispatch forces on the eight handlers. commitEpoch stays in main.zig because main itself builds the ambient clock from it; shared helpers stay pub and aliased. With this, main.zig holds only main, the verb dispatch, init, the shared helpers and the test surface -- the eleven-thousand-line file is now four cmd families plus a thin dispatch core. No helper duplicated, no cross-cmd import, test count unchanged. check-in: ae54e47b3c user: dmestas tags: trunk