Closes Stage 3's remaining obligations.
THE PTY TEST. Every other test in this lane checks a mechanism.
tests/long_line_readable_acceptance.rs checks the complaint: the
shipped binary, a real 80x24 PTY, one source line 200 columns wide,
and an assertion that its tail marker reaches the host. It bites —
`scripts/bite HEAD~2 src/editor.rs --test long_line_readable_acceptance`
against the pre-aa3cd4d editor never paints TAILZQX in 20s.
Its truncate control (an isolated init.lua pinning the mode) is what
makes that marker discriminating, and it is also the honest statement
of what truncate costs today: those bytes are not off-screen, they are
unreachable until Stage 4.
What it does not prove: the workspace has no screen model and no
vt100/termwiz/vte, so this shows the tail was WRITTEN to the terminal,
not which row a human would point at. That is nonetheless the whole of
the report — under truncation the bytes are never emitted at all.
§1.1 WAS WRONG, FOR NINETEEN REVISIONS. `editing.fill-column` is not
an orphaned registry setting "of the exact shape Stage 1 just fixed".
Both cited occurrences are inside `#[cfg(test)] mod tests` — fixture
names in round-trip tests covering one setting per ConfigKind. Two of
those five names are real; three, including this one, are defined
nowhere else in the tree. There is no shipped setting, so the Q#LL4
deliverable "sharpen its description" had no object.
The mechanism is worth more than the correction. A grep hit at a src/
path, a genuine `r.define(...)` call that is real API usage rather
than a mock, and `#[cfg(test)]` about fifty lines above the citation.
Every later revision inherited the conclusion instead of the evidence,
and three review rounds reasoned about the consequences of an orphaned
setting rather than re-checking that it existed. A file:line citation
is not a substitute for reading the scope it sits in.
Had it gone unchecked into implementation, Stage 3 would have shipped
an edit to a unit-test fixture believing it was rewording a
user-visible setting — a no-op with a misleading commit message.
§1.1 is withdrawn in place, keeping the original text and the
reasoning that produced it; §6's answer is unchanged (a setting that
does not exist is a stronger reason not to adopt it) and its premise
corrected. Both fixture sites now say they are fixtures. The approval
is not reopened: nothing else in the document rested on §1.1, which
argued for a display setting separate from fill-column — which is what
shipped.
AND ONE UNCLASSIFIABLE RED, logged as U1 in ci-red-signatures.md. A
`-p pmacs-gpu` run went 227/1 once; every run since is 228/0. The
failing test name was NOT captured, because I piped that command
through `tail -3` and discarded the failure block above the summary.
36 later runs are clean, 6 under deliberate concurrent load — which
per the rerun rule establishes intermittence only, and without a
selector not even that. Deliberately NOT matched against A1 despite
A1 also being GPU-headless-under-load: matching requires an exact
selector and every required fragment, and calling a shapeless red
"probably the known one" is the reputation-by-adjacency that file
exists to deny.
Gates: fmt; clippy --workspace --all-targets -D warnings; --lib
1917/0; --lib --features crdt 2102/0; line_wrap 6/0;
long_line_readable 2/0; folding 21/0; folding_stage2 48/0;
full_grid_resync 1/0; config_registry 16/0; m4 150/0;
PMACS_REQUIRE_GPU=1 -p pmacs-gpu 228/0 (see U1); git diff --check.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016bqGA6s9tTUFzYpbeW3tai
Section 5d.6 answered as (b): ScrollPosition and the pure classify go
in pmacs-protocol, string rendering stays in each frontend.
The reading that settles it is sharper than "shared vocabulary". Each
frontend computes its own local layout facts --- which rows are on
screen is a question only it can answer --- while the shared crate owns
the common semantic decision those facts feed. That is not presentation
leaking into the protocol crate; it is the DECISION placed where both
frontends are structurally unable to disagree, with rendering left
where it belongs.
Two properties bound the change: no wire message and no protocol
version bump, since classify is a pure function over values each side
already holds; and the one-copy-fixed defect from 5d.3 becomes
unrepresentable rather than reviewer-guarded, because there is only one
classifier to fix.
Q#LL8 approved. All eight questions answered. Implementation begins.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016bqGA6s9tTUFzYpbeW3tai
Revision 16 said the scroll formatter could keep its signature and
change only what callers pass. It cannot, and the byte fallback in
revision 17 made that unavoidable rather than merely untidy.
Every branch of format_scroll_indicator derives from total_lines:
total_lines <= 1 -> All
visible >= total_lines -> All
view_top == 0 -> Top
view_top + visible >= total_lines -> Bot
pct = (cursor_row + 1) * 100 / total_lines
Revision 17 removed the total. Passing byte counts makes the Bot branch
compare rows against bytes --- it would return plausible strings that
mean nothing. Passing any stand-in small enough to satisfy the guards
restores the false All this section exists to remove. And "local
predicates" is not something that signature can evaluate, because it
has no parameter for them.
Resolved by not asking it to. truncate calls the existing formatter
UNTOUCHED, with the same arguments in the same units, so its output is
byte-identical by construction rather than by assertion, and every
existing formatter test stays valid --- including the GPU's
format_scroll_indicator(0, 10, 1, 0) == "All", which correctly pins
line-space behavior. wrap calls a new classifier:
classify(first_visible: bool, last_visible: bool,
byte_pos: u64, byte_len: u64) -> ScrollPosition
All = first && last; Top = first && !last; Bot = last && !first;
otherwise Percent from bytes. No count of rows enters it, so the unit
mixing is not avoided but unrepresentable.
The actual mistake was trying to serve two genuinely different
contracts from one four-count signature. It could only do that by
making units implicit, which is how the contradiction arose. This is
5b.5's identity-case strategy applied to the indicator itself: the old
mode keeps the old code, and the new mode gets code shaped to it.
Leaves one question open. pmacs-gpu depends on pmacs-protocol only,
never on the pmacs lib, so format_scroll_indicator is duplicated
STRUCTURALLY and the classifier faces the same fork. Duplicating it
preserves exactly the condition that produced the earlier defect, where
one copy was fixed and the other was not. Sharing it through
pmacs-protocol makes the agreement structural rather than maintained,
which is the principle that chose byte-anchoring, additive sub_row, and
a content-derived cache key --- but it widens that crate from wire
vocabulary toward presentation, which is a COHERENCE section 16
layering question and not this lane's to settle alone.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016bqGA6s9tTUFzYpbeW3tai
Revision 16 gave the GPU its scroll-indicator total on the premise that
"cosmic-text already knows each line's visual height". It does not.
rebuild_code_slice feeds cosmic-text current_text[vstart..vend] and
nothing else, because Session S1 found that feeding the whole rope made
large-file editing O(file) per keystroke. The GPU's layout holds the
viewport slice plus overscan; it cannot yield total visual rows, nor
the cursor's or top's row ordinal.
Re-shaping the whole document to recover them would reintroduce exactly
the cost that design exists to prevent --- for a status-line readout.
So the aggregate is abandoned rather than relocated. NN% is computed
from BYTE POSITION in both frontends; truncate keeps today's
visible-line percentage. No total, no cache, no invalidation.
Three reasons it is abandoned rather than approximated. Rows-per-line
could be computed as ceil(width / cols) without shaping, but
cosmic-text decides the real break points, so the number could disagree
with what is on screen --- the same approximate-parity trap Q#LL5
rejected for whitespace wrapping. Letting the TUI use row ordinals and
the GPU use bytes would show two percentages for one buffer, which is
this lane's own defect a third time. And All/Top/Bot are unaffected
either way: they are local predicates, they stay exact, and they are
the states a user actually reads.
This retires the cache from revision 15 and the fold-key correction
from revision 16. That correction was right for the design as it stood;
the design moved under it. Section 5d.2 is marked SUPERSEDED rather
than deleted, because "the key was fixed" and "there is no key" are
different states and a later reader should be able to tell which one
happened here.
Adds the large-file guard as a witness rather than an intention: an
indicator paint must leave the GPU's view_range and shaped_top
untouched, must not lay out beyond the viewport in the TUI, and
open_100mb_under_200ms must still pass with wrap as the default mode.
Without those, the decision is an unenforced comment and a later
"improvement" to a real row count would silently restore O(file) work.
Known imprecision, stated rather than left to be discovered: under
folds a byte percentage counts hidden bytes. Folding is TUI-only today,
and it matches Emacs. It belongs to the GPU folding lane, not this one.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016bqGA6s9tTUFzYpbeW3tai
Two corrections to Q#LL8, both found by review of 1c9ff6a, and both the
same shape: a fix that read as complete because it was correct in one
of two places.
The GPU has its own scroll indicator. format_scroll_indicator is
DUPLICATED, not shared --- src/editor.rs:5509 and
pmacs-gpu/src/main.rs:10114, each with its own tests --- and the GPU
passes current_line_starts.len(), a source-line count. So revision 15
would have fixed the indicator in the TUI and left the GPU reporting
"All" for a one-line wrapped buffer.
That is worth naming plainly: it is this lane's own defect, reproduced
inside the section written to close it. The lane exists because two
frontends disagree for reasons nobody chose, and the fix disagreed for
exactly that reason one more time.
Both copies keep their signature. The formatter is a pure function over
counts and is correct as written; what changes is what the callers
pass --- visual rows rather than source lines, visible rows rather than
visible lines. Every existing formatter test stays valid, including the
GPU's own format_scroll_indicator(0, 10, 1, 0) == "All", which pins
line-space behavior and must not silently change meaning.
The lazy total's cache key omitted fold state. Folds are built per
rendered window and can be collapsed or expanded with no edit, no
resize and no mode change --- so all three of revision 15's key
components sit still while the projection underneath them moves. Cache
NN%, toggle a fold, and the stale total is served for the new
projection.
Now keyed on (buffer generation, content width, mode, fold projection),
and specifically on the projection's own components rather than a
revision counter on the fold registry. Components is one entry per
collapsed region, so comparing it is O(folds), and the key IS the thing
it guards --- it cannot be forgotten. A maintained counter can, on
every present and future mutation path, which is the same
did-you-remember hazard as LL7's buffer-switch trigger. Same principle
as byte-anchoring over a row index and additive sub_row over redefining
row: self-validating beats maintained.
Content width, not window width. Wrapping happens in the text area, and
the gutter's width changes at the line-count digit boundary (9 -> 10,
99 -> 100) --- something the GPU's sync_buffer_dimensions comment
already records for its own shaping. Keying on window width would serve
a stale total across that boundary.
Three witnesses added: the reported case in BOTH frontends, a "cache,
then toggle a fold" case that fails against revision 15's key, and a
digit-boundary case.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016bqGA6s9tTUFzYpbeW3tai
Two holes in revision 14, both found by review of this lane's own first
commit, and both would have been discovered during implementation at
much greater cost.
Q#LL7 --- the mode never reached the GPU. Section 4 resolves
ui.line-wrap into Viewport, which reaches the GRID renderer. The GPU is
not a grid consumer: it lays out locally, ignores CellDelta,
BufferSnapshot carries only CRDT bytes, and no InstanceMessage variant
expresses a wrap mode. So truncate would have changed the TUI and left
the GPU wrapping --- the two frontends still disagreeing, which is the
one thing this lane exists to fix. Q#LL5's "character wrap in both" was
equally unreachable: setting Wrap::Glyph at startup is not honoring a
mode that can change.
Specified as an additive variant at v22, appended after the current
final variant with the advertised baseline left at 20 --- the path
FontFacts took at v17 and the panel shapes at v21, and the baseline
constant's own doc reserves moving it for changes that cannot be
expressed additively. This one can.
It carries buffer_id, and is resent on attach, on config change, AND on
buffer switch. The third trigger is the one a FontFacts-shaped design
misses: font size is global, wrap mode is per buffer, so switching from
a truncate buffer to a wrap buffer changes the effective mode with no
config event at all. A design listening only to on_change is silently
wrong and passes every single-buffer test.
Q#LL8 --- the scroll indicator falsifies the locality claim. Revision
14 asserted every vertical consumer is local. format_scroll_indicator
is not: a one-line buffer wrapping to fifty screen rows has
total_lines == 1, so the first branch returns "All" while forty-nine
rows sit below the viewport. The indicator claims the whole buffer is
visible when almost none of it is.
The claim is narrowed rather than abandoned, because the distinction
that bounds the cost survives: a TOTAL is one number, lazily computed
and cached; a PREFIX-SUM INDEX is O(N) resident storage. Stage 3 needs
the first and still does not need the second. All, Top and Bot need no
aggregate at all --- each is a local predicate falling out of the
render walk --- so only NN% pays, which matters because the M1 gate
measures open time on a 100MB file.
Also fixes a notation hazard. Section 7 said pos_to_display returns
"the visual row", which reads as redefining row --- the exact thing
5b.5 forbids, stated two sections apart. Every wrap-point example is
now the explicit triple {row, sub_row, col}. Writing them out makes the
point visible: both coordinates at a soft break share the same row,
because a wrap does not cross a source line. That is the information a
redefinition would have destroyed, and the pair notation hid it.
Status returns to not-approved. Both questions change what gets built,
not how, so implementation waits on them.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016bqGA6s9tTUFzYpbeW3tai
A line wider than the window cannot be read past the edge in the TUI.
The GPU is not in that state --- it already wraps --- so the
cross-frontend defect is not unreadability. It is that NEITHER behavior
was chosen: the TUI truncates because a cell walk breaks at max_cols,
the GPU wraps because cosmic-text's Wrap::WordOrGlyph default was never
overridden. Two accidents that disagree, and no way to state a
preference in either.
Eleven revisions of review, and the corrections were the substance.
Revision 1 claimed both frontends render from the same CellGrid, which
inverted the entire cost model --- pmacs-gpu ignores the grid variants
and lays out locally, and its own comment says so. Later rounds caught
an impossible round-trip invariant, a "collision" between two
coordinates that were one position, an off-grid argument against a
function that has no grid, a false binary for view_top, and a
renumbered visible-line space that does not exist. Each is recorded
with its reasoning rather than quietly fixed, because the pattern ---
an assertion that reads as precise while resting on something
unverified --- is more useful to the next reader than any single fix.
All six questions are answered and the framing is approved:
LL1 wrap + truncate, default wrap; horizontal scroll is Stage 4
LL2 buffer-local mode, resolved into Viewport like folds
LL4 do not adopt editing.fill-column; ours is ui.line-wrap
LL5 character wrap in BOTH frontends
LL6 no global map; byte-anchored view_top; additive DisplayCoord
Two of those deserve to be found later rather than discovered:
GUI users lose word wrap. Character-wrap parity is cheap, true, and
matches Emacs, whose default wrap is also a character wrap. But the GPU
has word-wrapped since it existed and nobody opted into losing it. The
alternative was a UAX #14 dependency, because a whitespace-based grid
wrap would give only APPROXIMATE parity against cosmic-text's Unicode
line breaking --- which is worse than honest divergence, since it looks
unified until it is not.
The audit strategy is asymmetric deliberately. The coordinate functions
gain a required context parameter so the compiler enumerates every call
site; DisplayCoord gains an additive sub_row so untouched consumers
stay CORRECT rather than merely findable. Compiler-enforced where
enforcement is possible, correct-by-default where it is not.
Also corrects two ledger headers that still said OPEN for PRs merged
earlier today (#218 at 09:59Z, #217's absorption; #219 at 13:41Z).
Neither lane is removed --- rule 4 removes a lane when its ARC is done,
not when a PR merges, and the QoL arc has this stage left. Read each
block before cutting it.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016bqGA6s9tTUFzYpbeW3tai