#221 merged, so the long-lines lane is REWRITTEN rather than removed —
rule 4 removes a lane when its arc is done, and Stage 4 is ahead. Stage
3's durable facts move to the handoff §1, which is rule 4's actual
precondition.
THE FRAMING LEADS WITH THE FACT MOST LIKELY TO INVERT ITS OWN COST
ESTIMATE, because that is what Stage 3 revision 1 got wrong. The GPU
cannot honor horizontal scroll through cosmic-text: `Scroll::horizontal`
is discarded throughout, and not by oversight — glyphon 0.11 never
applies it when placing glyphs. Documented in three places and asserted
by three tests. So the GPU's half needs a mechanism that does not exist,
touching caret placement, decoration geometry, and hit testing, each of
which assumes x starts at `text_left()`. That is Q#HS1: whether the GPU
is in Stage 4 at all.
Also verified rather than recalled: there is NO horizontal scroll
anywhere in the tree (greenfield, not an extension); `paint_line` starts
every walk at column 0, so `view_left` enters the functions Stage 3 just
rewrote and the wrap rule must stay written once; `view_top` is
persisted per leaf at DESKTOP_VERSION 1; `scroll_window`'s comment
already records the cursor-follow hazard; and `goal_col` is unexamined
horizontal state on the same window.
Six questions, each with my vote and the argument against it. The one I
am least comfortable with is Q#HS6: Stage 4 adds capability that exists
only under a NON-DEFAULT mode, which is a conditional surface rather
than a uniform improvement — and Stage 3 chose `wrap` as the default
partly BECAUSE scroll did not exist. If scroll makes `truncate` good,
that default deserves re-examination rather than inheritance.
ALSO A GATE CORRECTION, and it changes what I said in 4d70ff6. I wrote
that "the touched acceptance suites" is the standing gate. That is
CLAUDE.md's list. `docs/agent-handoff.md` §3 — which CLAUDE.md tells me
to read FIRST — already required `cargo test --workspace -- --skip
basedpyright`, a full sweep. I ran the short list. So the eight broken
version assertions were not a gap in the documented gates; they were me
following a summary instead of the gate suite.
§3 now says so, and adds the protocol-bump form (`--tests
--no-fail-fast` in both feature configurations), because even the full
sweep stops at the first failing target and builds one configuration —
it would have shown one or two of the eight, not all of them.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016bqGA6s9tTUFzYpbeW3tai
