Both blockers were the recurring defect sitting inside the fix written to close
it: a check whose TEXT claims more than its FIXTURE can observe. Both survived a
green 19-file suite on 8501e05.
max(floors) -> max(floors[-2:]) +5 bytes. 12c2's only counterfactual raised
the LAST pack, and every window ending at the roster's end follows the last
pack. The check said "the reduction reads every entry"; the data reached "it
reads the last entry".
self.packs -> self.packs[:2] +4 bytes. All three 12g runs drove a TWO-pack
roster, where [:2] IS the roster. The check said "what is reduced is the ROSTER
and not a POSITION in it"; the true claim was the narrower "no SINGLE-POSITION
slice passes all three runs".
The prose is cut back to what the old data reaches, and new data added for the
rest. No app/ file is touched - app/peakguard.py and app/main.py are byte-identical
to 8501e05.
12c2 - the pure function:
* a ROSTER SET: the same four simulated cut-outs with the deepest moved to each
of the four positions.
* a computed FAMILY TABLE of fourteen rewrites, printed, with the roster that
kills each. A member with an empty kill list takes the check RED naming it.
* a LENGTH SWEEP: 78 rosters, lengths 1-12, deepest at every position of each.
Closes every head window max(floors[:w]) and tail window max(floors[-w:]) of
width 1-11 in one property.
12g - the call site:
* _floor_reaching_decide() takes *floors; extra units join through the same
second_inverter() hook.
* THREE-pack runs with the deep cut-out at index 0, 1 and 2. Every positional
slice of a three-pack roster drops a position, and the run whose deep pack
sits there answers the option where the roster answers the cut-out.
* a POSITIONAL-SLICE TABLE computed against the REAL Controller.packs each of
the six cycles ran and the REAL PeakDecision.soc_floor it produced.
* an EXACT STRUCTURAL PIN on the roster argument's identity. Not the substring
test round 2 removed: "self.packs" in expr is TRUE of every slice;
ast.unparse(arg) == "self.packs" is FALSE of all of them.
THE GENERAL LAW, and why the pin is there: a fixture of N packs cannot separate
two reductions that agree on N packs, and the regress does not terminate in a
fixture. [:1] needed two packs, [:2] three, [:3] four. This round's own battery
found self.packs[:3] (+4) and self.packs[-3:] (+5) surviving all six behavioural
runs; the structural pin is what closes them, and one more pack would only have
moved the hole.
Battery: 46 mutations over the reduction, the call site, Controller.packs and
pack_floor_pct()'s conjunction. Bytecode purged and counted 23 -> 0 for each.
43 red, 3 survivors, all three recorded:
max(floors[:12]) / max(floors[-12:]) NOT CAUGHT - needs a 13-pack roster,
reported with its size, row 27.
max(set(floors)) EQUIVALENT - max is duplicate-invariant.
(list(reversed(self.packs)) is equivalent too and is red on the structural pin.)
In-process mutation rows 24-27 record all of it, including the not-caught one.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BwRLw7eKYj2byVdwB6kbjU
