From 397ea89795c8375a658a826b9fe4a671815170a9 Mon Sep 17 00:00:00 2001 From: Vuong Hoang Date: Wed, 23 Sep 2026 00:04:59 -0700 Subject: [PATCH] fix(u7): six defects from the heid bug-hunt panel, and five vacuous falsifiers MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Cross-frontier panel (Gróa/Hulda/Regin/Kimi) on U7's diff, thread 01M368G2Y0JMTJ2T7M3JMTXV5Z. Four of the six fixes are for defects no test in this repo could have caught, and the panel's guard-strength passes found five of my own falsifiers green under the exact change they forbade. THE 4-OF-4 FINDING — the group anchor could land on the WRONG artifact. The anchor was the raw rel spliced into an href fragment while the tile id was equally raw. A browser matches a fragment against ids RAW FIRST and only then percent-decoded, so raw-on-both-sides is not merely unencoded, it is AMBIGUOUS: with `a b.png` and `a%20b.png` in one booth, the first's href resolves to the fragment `item-a%20b.png` and the raw pass matches the SECOND file's id. That is the misfiled-judgment failure invariant 6 exists to prevent, arriving through a path invariant 6 never looked at. Both sides now use `Item.url` (`quote(rel, safe="/")`), which is injective here and is the convention booth_flag has always used. The original test asserted the href occurred as SOME id on the page — true while pointing at the wrong one. GRÓA'S STRONGEST SOLO — a zero-hit filter removed the way back. The rail was gated on the FILTERED list, so a valid filter with no matches removed the rail, the filter links and the route back to `all`, while the empty-booth branch announced the booth was empty with rail.total still holding the real count. No recovery without editing the address bar, and it degraded the same way with JavaScript off, on the surface the operator actually reviews on. Gated on all_items now, with an explicit no-match row. HULDA — one unrepresentable filename took out the INDEX, not just its booth. A non-UTF-8 filename reaches CPython as a surrogate and quote() raises on it, outside any per-item handler. booth_items feeds list_booths, so one 0xff byte in one booth's filename 500s every booth's card. Such a file cannot be linked, served or zipped, so it is skipped like a dotfile. HULDA — the `f` shortcut has never worked. The selector named `.flagbtn`, which nothing in this repo emits, so it fell through to the hidden target input; clicking a hidden input does not submit its form, and the handler called preventDefault anyway. Now clicks the flag form's real button, verified end to end in a real browser. GRÓA — a group jump was undone by the next keypress. The jump scrolls, the cursor stayed at -1, and the next arrow focused tile 0 and scrolled back. The cursor now picks up from the viewport, which also fixes the general scroll-then-arrow case. Asserted on real scroll geometry in Chromium. HULDA — the caption sidecar was read whole before being truncated, so a pathological file was a MemoryError the OSError handler does not catch. Bounded at the read, and deliberately NOT by st_size: a FIFO reports 0. ACCEPTED KNOWN RISKS, both now documented rather than implied: no cap on rail row count (1,000 groups of two would render 1,000 rows; the largest live booth is 66 items and picking a cap without a booth that needs one is invented work), and Item.group sits mid-dataclass (one construction site, keyword-only, grepped). The docstring now names the UPPER median explicitly — two arms flagged that "the middle group" admits both readings for an even count. FIVE VACUOUS FALSIFIERS, found by the arms and not by me: the anchor test survived v[0]->v[-1]; the informativeness guard survived sizes[-1]; the group count survived len(v)+1; the zero-hit filter test used a fixture that HAD hits; and the escaping test asserted over the whole page, so it went red on a code comment. All rewritten, all mutation-proved. The table is up to 20 rows and one drifted when I changed the line under it — reported by the harness, not silently skipped, which is the behaviour tests/test_mutation_check.py exists to hold. 660 green; 20/20 proved. Deployed; 21/21 booths 200. Held for design-dev, not fixed here: Gróa's finding that the sticky rail has no scroll-margin, so a fragment jump tucks the target under it. It is one line in base.html, the file he is rewriting from scratch. --- booth/app.py | 34 ++++++- booth/items.py | 30 +++++- booth/templates/booth.html | 50 ++++++++-- tests/mutations/u7_navigation.toml | 78 ++++++++++++++- tests/test_embed_browser.py | 69 ++++++++++++++ tests/test_items.py | 40 ++++++++ tests/test_navigation.py | 147 +++++++++++++++++++++++++++++ 7 files changed, 433 insertions(+), 15 deletions(-) diff --git a/booth/app.py b/booth/app.py index c1e434c..2fe3b3d 100644 --- a/booth/app.py +++ b/booth/app.py @@ -1036,7 +1036,11 @@ def create_app( insertion order, so walking `shown` once IS the rule. ⚠ THE RAIL IS ABSENT UNLESS GROUPING IS INFORMATIVE: two or more - groups, and the middle group holding more than one item. TWO + groups, and the UPPER MEDIAN group holding more than one item — for an + even count that is the larger of the two central sizes, so `[1, 2]` + renders and `[1, 1, 2]` does not. Named precisely because "the middle + group" admitted both readings and two panel arms flagged the ambiguity. + TWO degeneracies, not one. The contract named only the first -- `sindra` and `sc-iso-spread` put every file in ONE group, and a rail with a single row cannot navigate. The second is the one the live set @@ -1051,13 +1055,33 @@ def create_app( if it["group"] is not None: by_group.setdefault(it["group"], []).append(it) sizes = sorted(len(v) for v in by_group.values()) + # `sizes[len(sizes) // 2]` is the UPPER median; the `< 2` term + # short-circuits, so the index is always valid. No upper bound on the + # ROW COUNT: 1,000 groups of two pass this and render a 1,000-row rail. + # Accepted known risk — the largest live booth is 66 items and picking + # a cap without a booth that needs one is the invented work the roadmap + # gate exists to prevent. Raised 2-of-4 by the panel, 2026-09-22. if len(sizes) < 2 or sizes[len(sizes) // 2] <= 1: return [] return [ - # The anchor is the FIRST member's existing tile id. The template - # already stamps `id="item-"` on every figure; minting a - # parallel `#group-` would be a second identity for one tile. - {"key": k, "n": len(v), "anchor": f"item-{v[0]['name']}"} + # THE ANCHOR IS BUILT FROM `url`, NOT `name`, and the template + # stamps the tile id from `url` too. Both sides must use the same + # percent-encoded string or the jump lands on the wrong artifact. + # + # A browser matches a fragment against ids RAW FIRST and only then + # percent-decoded, so a raw rel on both sides is not merely + # "unencoded" — it is AMBIGUOUS. With `a b.png` and `a%20b.png` in + # one booth, the first's href resolves to the fragment + # `item-a%20b.png` and the raw pass matches the SECOND file's id. + # `Item.url` is `quote(rel, safe="/")`, which is injective here + # (`a b` -> `a%20b`, `a%20b` -> `a%2520b`), and it is the convention + # `booth_flag` has always used for exactly this reason. + # + # Found 4-of-4 by the heid bug-hunt panel, 2026-09-22. The original + # anchor test could not see it: it asserted the href occurred as + # SOME id on the page, which stayed true while pointing at the wrong + # one. + {"key": k, "n": len(v), "anchor": f"item-{v[0]['url']}"} for k, v in by_group.items() ] diff --git a/booth/items.py b/booth/items.py index 77b428a..4f33621 100644 --- a/booth/items.py +++ b/booth/items.py @@ -197,7 +197,18 @@ def _resolve_captions(by_rel: dict[str, Path]) -> tuple[dict[str, str], set[str] if target is not None: try: - caption[target] = p.read_text(errors="replace").strip()[:CAPTION_MAX] + # BOUNDED AT THE READ. `read_text()` pulled the whole sidecar + # into memory before the slice trimmed it, so a pathological + # file was a MemoryError — which the OSError handler below does + # not catch — rather than a missing caption. + # + # Deliberately NOT bounded by st_size: a FIFO reports 0 and a + # bound that trusts it inherits what it does not mean, which is + # the hang in persistent-memory.d/2026-09-22-size-cap-opened-a-hang.md. + # The factor of 4 is UTF-8's worst case, so CAPTION_MAX + # characters always survive the byte bound. + with p.open("r", errors="replace") as fh: + caption[target] = fh.read(CAPTION_MAX * 4).strip()[:CAPTION_MAX] except OSError: pass sidecars.add(rel) @@ -222,7 +233,22 @@ def booth_items(booth: Path) -> list[Item]: continue if is_ask_file(p.name) or is_answer_file(p.name): continue - by_rel[p.relative_to(booth).as_posix()] = p + rel = p.relative_to(booth).as_posix() + try: + quote(rel, safe="/") + except UnicodeEncodeError: + # A non-UTF-8 filename reaches CPython as a surrogate escape, and + # `quote` raises on it. This used to happen at Item construction, + # OUTSIDE any per-item handler — so one 0xff byte in one filename + # took out that booth's page AND the index for every booth, because + # `list_booths` calls this too. The repo's posture is that a damaged + # file costs its own tile and never the page. + # + # Skipped rather than rescued: a name that cannot be percent-encoded + # cannot be linked, served or zipped either, so there is no item to + # render. Found by the heid bug-hunt panel (hulda), 2026-09-22. + continue + by_rel[rel] = p caption, sidecars = _resolve_captions(by_rel) blurred = read_blurred(booth) # ONE read per call, not one per item diff --git a/booth/templates/booth.html b/booth/templates/booth.html index 2ea19df..9faef1e 100644 --- a/booth/templates/booth.html +++ b/booth/templates/booth.html @@ -237,9 +237,19 @@ {% endif %} -{% if not items and not board and not marks %} +{# ⚠ THE RAIL IS GATED ON `all_items`, NOT `items`, AND THAT IS THE WHOLE + POINT. `items` is the FILTERED list, so gating on it meant a valid filter + with zero hits removed the rail, the filter links and the only way back to + `all` — while the empty-booth branch below announced the booth was empty + with `rail.total` still holding the real count. No recovery without editing + the address bar, and it failed the same way with JavaScript off, on the + surface the operator actually reviews on. + + Found by the heid bug-hunt panel (gróa, 2026-09-22), whose own note called + it the finding most likely to bite users this week. #} +{% if not all_items and not board and not marks %}
This booth is empty.
-{% elif items %} +{% elif all_items %} {# `elif items` and not a bare `else`: a board booth has NO gallery items (its links.md is rendered as the board above and filtered out), so a plain else would emit an empty
under the board. #} @@ -276,6 +286,12 @@ {% endif %}
+ {% if not items %} + {# An empty FILTER, not an empty booth. The rail above is still rendered, so + the way back to `all` is one click. #} +
No items match the {{ filter }} filter. + show all {{ rail.total }}
+ {% endif %}