Implements docs/folding-stage2-framing.md rev 4. The daemon grid
renderer now consults the fold store: hidden lines are omitted, rows
below shift up, and every consumer that assumed
`display_row = source_line - view_top` routes through one shared
projection. No wire schema change and no protocol bump (Bet B6) — the
collapse is entirely daemon-side; the GPU path is Stage 3.
The spine (Q#FD12) is `src/fold_view.rs`: a `VisibleLineMap` derived
from `FoldRegistry::folds` plus a window's line offsets and never
stored. Its unit is a merged **hidden component** — overlapping OR
adjacent hidden intervals unioned, each keeping the one visible
`head_line` and that line's exact `head_position`. Adjacent intervals
merge because the later fold's head is itself hidden, which is what
makes nesting, shared heads, and crossing overlap all resolve to a
head that can actually render (round-3 F2).
Instances are short-lived and built **per rendered window** and **per
command/event operation**, never once per frame: `paint_frame` renders
several windows that may show different buffers, so a singleton would
leak one pane's folds into another (round-2 F2). The render instance
rides on a lifetime-bearing `Viewport<'a>` as `Option<&'a
VisibleLineMap>` — a shared ref is `Copy`, so `Viewport` stays `Copy`
(Bet B7).
Rendering:
- `TextView::render` walks visible lines; the head line gets a
trailing content-area ellipsis (Q#FD13).
- The gutter walks visible lines too: Absolute keeps the raw `line+1`,
Relative/Hybrid measure VISIBLE distance anchored on the cursor's
visible head (Q#FD14). The fold glyph takes the col-0 sign cell only
when a gutter exists — line numbers default to Off, so with no gutter
the ellipsis is the sole marker (Q#FD20, round-1 F3). A diagnostic
clamped onto the head wins that cell by paint order.
- A diagnostic on a hidden line clamps its SIGN to the outermost
visible head (most-severe merge); the squiggle needs a real row, so
only the sign clamps (Q#FD15).
- Caret, local selection endpoints, and peer cursors project via
`visible_position_of` — the head row AND the head's end-of-content
column, never an arbitrary column (round-2 F3). Peer presence derives
the RECIPIENT window's map.
- Style/search/completion overlays route through
`Viewport::row_offset_of`; the mode-line indicator reckons in
visible-line space.
Command/event time is scoped per frontend (Q#FD21): a
`fold_projection` flag on `FrontendView`, set at attach from the
negotiated `semantic_render` bit (grid ⇒ true, semantic ⇒ false until
Stage 3, LOCAL ⇒ true) and never inferred from a `FrontendId` (Bet
B8). Without it, shared `EditorCore` motion would make a simultaneous
unfolded GPU session's cursor skip lines it still displays. The map's
two axes stay separate (round-3 F1): the acting frontend supplies the
policy, the operation's TARGET window supplies the buffer — a wheel
event names a pane without activating it.
Motion (Q#FD17, ruled: include), paging, wheel, the click inverse, and
the auto-scroll clamp all step by visible lines under that gate;
motion from a hidden logical cursor normalizes to the visible head
first. `view_top` stays a source-line index (Bet B5), set only via
`clamp_view_top` so it never rests hidden.
Unfold widening (Q#FD19): the pre-edit unfold moves to the top of
`apply_active_edit` — one funnel that subsumes the six primitives'
calls and covers yank + query-replace, both of which place point at
the edit site first. Interactive Lua mutators hook the common
`run_buffer_edit`, above the managed/bypass split, gated on
`InteractiveCommandOrigin` AND the edit targeting that frontend's
active-window buffer. The remote/optimistic-CRDT path stays excluded
(Stage 3); undo/redo unfold stays deferred.
Acceptance: `tests/folding_stage2_acceptance.rs`, 35 tests asserting
on the real `paint_frame` cell grid, covering framing items 1–14
including crossing folds, a nested deeply-hidden cursor, a split of
two different buffers with an inactive-pane wheel, and simultaneous
grid+semantic motion.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Q5BkezMppbpCgGAYk2ftxV
Share one fixed eight-column tab-stop contract across core and GPU renderers. Consolidate byte-to-display-column accounting, expand GPU code tabs with source provenance, align caret/hit/decoration geometry, and refresh minimap projection on edits.
Finding-by-finding (framing revision 12; bites via scripts/bite
against a49adc2):
1. Render-view attachment is idempotent and split-complete. Overlays
expose overlay_identity (the span store's allocation address);
Window::ensure_overlay attaches a store-backed render view AT
MOST once per window — pre-fix every switch into the buffer
blindly pushed another copy onto EVERY matching window, so
passive panes accumulated duplicates, each cloning all spans and
rescanning the buffer per frame. A same-buffer split copies
clonable overlays to the new pane via clone_for_split (splits
fire no switch hook and started with an empty overlay list — the
new compilation pane rendered unstyled). Bites: the acceptance
test asserts both panes styled with exactly one attachment
IMMEDIATELY post-split (before any switch could heal the pane
through the attach-to-all path — the first draft asserted only
after bouncing and was vacuous against the split fix), then
re-asserts after three bounce cycles; fails against pre-fix
editor_core.rs (split half) and pre-fix mod.rs (accumulation
half) independently. Units pin ensure-once and split-copy/no-copy.
2. The translator ignores pure no-op edits (buffers deliberately
broadcast empty inserts/deletes for callers that count calls):
pre-fix each interior no-op split the containing span into two
adjacent fragments — unbounded list growth for repeated no-ops at
distinct positions, and a no-op at a UTF-8 continuation byte
minted a mid-codepoint span boundary. Units now cover genuine
EditOp::Insert (the round-5 "insertion" unit only replaced) and
no-ops at five interior positions including the continuation
byte; the Lua twin (r6f2) bites via the overlay.rs swap — as a
compile failure, since that file also carries the round-6
identity machinery (weaker evidence, per the bite script's
caveat; the in-crate unit pins the behavior directly).
3. StyleOverlayHandleLua retains the buffer and translator ViewId
and exposes idempotent dispose(): detaches the buffer-attached
translator (later edits stop paying for it) and removes every
window render view over the store. Documented lifetime contract:
one handle per buffer incarnation (the compile/REPL discipline)
needs no disposal — the buffer's death frees it; repeated
creation on a long-lived buffer must dispose retired handles.
Bite: r6f3 (translate → dispose → edit must NOT move the span,
render views gone, double-dispose safe) fails against pre-fix
mod.rs.
Gates: fmt; clippy workspace all-targets; lib 1534; crdt lib 1708;
compile acceptance 63; crdt acceptance 3; m4 101; m6.4 15; m6.5 11;
m6.8 8; GPU 59; workspace sweep 2523/0 (one m8-class flake, clean on
rerun); git diff --check.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01VoiEyuPjoBhvwACf8HAnLB
Finding-by-finding (framing revision 11; bites via scripts/bite
against 6793edc):
1. Style-span coordinate translation belongs to the BUFFER. A new
BufferStyleSpanTranslator is attached by
pmacs.buffer.add_style_overlay and sees every edit exactly once —
bypass writes, undo/redo, remote CRDT ops — independent of window
count or visibility; the window-attached BufferStyleOverlay
copies are render-only (on_edit removed). Pre-fix each attached
view translated the shared store: start_run's explicit attach
duplicated the after-switch hook's (switch_buffer fires it
synchronously), so the normal path shifted later spans TWICE per
byte-delta rewrite, splits multiplied further, and a hidden
buffer shifted ZERO times. The redundant attach is removed;
correctness no longer depends on attachment discipline. Bites:
per-cell rendered assertions active (red a, blue bc, CR, red é →
é red, b/c blue) and hidden (run finishes with the buffer in no
window; switch back renders true colors); three direct units pin
exactly-once with extra render views attached.
2. Translation preserves the untouched fragments of a partially
overlapped span: left of the replaced range keeps its styling,
right of it shifts by the length delta, only the rewritten bytes
lose theirs (the writer styles what it writes; inserted bytes
inherit nothing). Pre-fix any overlap dropped the WHOLE span —
red abc, SGR reset, CR, X left bc unstyled; zero translation
painted the default X red instead. Bite: exact (glyph, fg) cells
X=default, b/c=red — any_styled_cell cannot see either failure.
3. The per-CR/BS/erase-line whole-prefix scan is gone:
slot.line_start is tracked — advanced at every \n (append helper
+ the mid-line newline branch), read O(1) by the rewind paths,
reset on run start/resync/raw marker appends. Measured on 2 MB of
output + 3000 CR updates (release): 2.52s pre-fix → 0.67s
post-fix (remainder is fixture-bound; pre-fix cost grows with
buffer size). No correctness bite is possible for a pure perf fix
— the committed test pins the tracked value's behavior across
multi-line appends, batch-boundary CR, repeated CR, erase-line,
and recovery paths, and passes on both implementations by design.
Gates: fmt; clippy workspace all-targets; lib 1531; crdt lib 1705;
compile acceptance 60; crdt acceptance 3; m4 101; m6.4 15; m6.5 11;
m6.8 8; GPU 59; workspace sweep 2517/0; git diff --check.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01VoiEyuPjoBhvwACf8HAnLB
Sub-arc 2 of the UX arc, TUI half. When a window reserves a line-number
gutter, lines with diagnostics get a severity-colored sign glyph (E/W/I/H)
in the gutter's leading column — closing the last deferred Task #23 item.
No protocol/daemon change: the per-line severity is already frontend-side
(the diag store the DiagnosticView already reads).
- `Viewport` gains `gutter_w` so overlays can reach the gutter's leading
column at `cell_origin.col - gutter_w`; the text area is already shifted
past it, so viewport-relative painters stay gutter-agnostic.
- The gutter's number pass now runs *before* the overlays (was after), so
the DiagnosticView can draw its sign into the gutter's blanked leading
column without the number pass erasing it.
- DiagnosticView: with a gutter, draw the severity sign glyph colored by
`underline_color()`; without one, keep the legacy column-0 background
marker (the "fake gutter" that predates a real gutter column). Extracted
to `paint_line_markers` to keep `render` under the line cap.
The number never reaches column 0 (>=1 leading pad by construction), so
sign and number coexist. Diagnostic signs currently ride the line-number
gutter (visible when line numbers are on); a signs-without-numbers mode is
deferred.
Test: gutter_sign_replaces_the_column_marker_when_a_gutter_is_reserved.
Validated: fmt + clippy --all-targets clean both flavors; 1441 lib + 22
diag tests pass. Needs a TUI eyeball before the GPU half.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_014TXbAwk27agwhrNNrhLi2U
M4.6 follow-up piece 2. `Style` gains `underline_color: Color`
(Default = follow the text color) so a diagnostic squiggle can be
red/yellow/cyan/gray without clobbering the syntax color of the
text it underlines — exactly why error_style() left its 'red'
unwired until now.
The wire consequence: Style rides inside Cell / CellDelta /
Snapshot / StyleSpans, so this is the protocol's first
encoding-breaking change. PROTOCOL_VERSION 5 → 6 and
SUPPORTED_PROTOCOL_VERSIONS narrows to [6]: postcard is not
self-describing, so no per-session send gate can keep a v5 peer
decoding v6 cells — a mismatched pair now fails the handshake with
a clean VersionMismatch instead of garbling mid-session. Version
policy tests rewritten to pin the new contract.
Surface wiring:
- diag.rs: per-severity underline_color (indexed 1/3/6/8).
- frontend.rs: kitty-style CSI 4:N for Double/Curly/Dotted/Dashed
(previously flattened to plain SGR 4) + SGR 58:5/58:2 emission.
- ansi.rs: parse SGR 58/59 with the 38/48 extended-color grammar.
- overlay.rs merge_styles: non-default-wins, like fg/bg/underline.
- lua_bindings.rs: underline_color on Lua style tables.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Levi Neuwirth