Stage 2 of docs/terminal-config-and-copy-mode-framing.md (rev 4,
approved). `M-x terminal.copy-mode`, or `C-t` in a terminal buffer —
physically `C-c C-t`, since every unescaped key goes to the child —
materializes the retained scrollback into an ordinary read-only,
path-less buffer, with `g` to re-snapshot and `q` to return.
No protocol change.
Materializing is the whole design. isearch, motion, selection and the
kill ring work with no new substrate because the snapshot is a rope, so
SearchStore and the existing match painting apply unchanged. And "keys
must not reach the child" dissolves structurally rather than being
guarded: the transport arm keys on is_terminal(buffer_id), and a
snapshot is not a terminal, so the arm never fires. The
dispatch-shadow count stays at six and describe-key keeps telling the
truth — asserted directly, since that is the observable difference
between the buffer-local idiom and a shadow.
One serializer, not two (Q#TC7). `copy_retained` builds a whole-range
selection and hands it to `copy_selection_bytes`; a second walk would
re-derive soft-wrap joining, wide-glyph continuation, cluster bytes and
per-row trailing-blank trimming, and the two would drift. Four unit
pins in view.rs assert exact bytes against the same projection fixtures
that pin the serializer itself.
Q#TC6a is implemented as two calls, and the second is the load-bearing
one: an intercept guards dispatch only, and no Lua binding sets
Buffer::read_only, so set_round_trip_input is what keeps a replica
frontend from applying optimistically and emitting an op that would
pass ensure_writable and mutate both sides. Acceptance 16 pins that
UNGATED, because CI never compiles the crdt feature.
Eight of nine criteria. Criterion 17's semantic-frontend end-to-end pin
is deliberately absent: the optimistic apply lives only in
pmacs-gpu/src/main.rs and the headless SemanticClient has no optimistic
path, so a faithful test needs the real GPU binary — the a37
foundation, which CI never compiles, silently returns ok when the
binary is unbuilt, and is load-sensitive. Both halves of the mechanism
are pinned ungated instead (16, and 16b for the hazard); the wire-level
half stays an explicit obligation of the CI crdt-coverage lane.
Substrate fact found while wiring lifecycle: TerminalManager::prune
REACTS to a buffer already gone from the registry rather than removing
one, so a child exiting leaves both the terminal and its snapshot
alive. That is why on_removed is a sound teardown hook, and why a
finished command's output stays readable.
Five bites, five different wrong implementations, each failing exactly
one test: removing set_round_trip_input fails acceptance 16 in the
DEFAULT configuration; a naive independent serializer fails all four
unit pins, with the diffs naming each drift mode; making re-invoke
create a fresh buffer fails 18; dropping the kill-with-terminal
teardown fails 18; removing the intercept fails 16b.
COHERENCE.md: §6 gains this as the worked example that a modal-looking
feature need not become a shadow; §11 records the scope="global"
deferral's second live case, making the argument for both registry
deferrals cumulative; §2 step 8 gains copy mode and keeps the
still-missing close command named.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016gGQC6eqHJVbZJ5Hg7aLer
Levi Neuwirth
1b1e599070