A seat in the composer tool row, left of the model select, showing the preset
THIS session runs — its own recorded one, not the deployment default, because a
resumed session runs what it was created with. `SessionSummary` carries
`agentPreset` for that, alongside `cwd` and `origin`.
The switch exists only while the conversation has not started. After the first
turn the seat becomes a plain label rather than a disabled menu: a greyed
control reads as "temporarily unavailable", when in fact the choice is gone for
good. The seat never asks in that state, and the host refuses independently
with `agent-preset-locked`, so a stale client cannot slip one past it.
A rejected switch restores the previous value and surfaces the host's message
rather than leaving the seat showing something the session is not running.
ConversationSession seeds a stored draft in its own mount effect, and a parent's mount effect runs after its children's — so the unlock effect measured an empty mirror and never ran again for the draft that then appeared, leaving a restored long draft showing its head with the caret at its end. The effect now depends on the draft being non-empty; clearing on send and typing the first character flip it too, where both the focus and the reveal are no-ops. Pre-existing (the old geometry did not scroll for a programmatic value change either), fixed here because the reveal now exists.
Also from review: the golden's paste goes back to a block NOT ending in a newline, so the collapsed branch keeps a real engine under it while the standalone case owns the after-newline branch; the shared line-height rule names the reveal as its third consumer.
A caret straight after a newline is on a line with nothing to measure — the shape a trailing-newline draft ends in. chromium returns no client rects at all for the collapsed position (an all-zero box, which sent the reveal upward instead), firefox reports the line above, WebKit the right one. Measure the newline the caret just left and step one line down: all three then land on 649 of 652 with the caret's line at 315 inside the 336px box. The browser case now pastes a newline-terminated block, and fails 'expected 0 to be greater than 0' without the rule.
The reveal spec wraps setStart to record which layer and index the composer measures; capturing the method directly trips the unbound-method rule, which the pre-commit lint caught after a --no-verify commit slipped it through.
preventScroll stopped the browser from revealing a focus nobody gestured for, and took the caret with it. The composer DOM is reused across sessions, so switching to a longer draft keeps the previous offset while the value swap puts the caret at the new draft's end: measured on all three engines, 940px below a box sitting at 0, where the old geometry reached the caret at 628. The unlock effect now suppresses the browser's walk and reveals the caret in its own scrollport, landing at 625 of 628. The focus-keeping mousedown gets preventScroll too and needs no reveal. revealCaret returns early when the box cannot scroll: the draft fits, so every caret is already in view.
Pasting a long block left the view where it was while the caret sat at the
end of what was pasted. Paste, ctrl/meta-Enter newline and cut all suppress
the native edit — the machine owns the draft and the undo log — and restore
the caret with `setSelectionRange`, which reveals nothing: measured in
chromium and WebKit, before this branch as well as on it. Firefox happened to
reveal it, in the old geometry only.
The three restores now share one helper that measures the caret against the
hidden mirror — same draft, same metrics, same wrap width, so a Range
collapsed at the caret's index reports where the caret is without a caret API
— and scrolls the scrollport the minimum that brings the line inside, which
is what the browser does for typing. One scrollport is what makes this
possible at all: the reveal is finally a single offset to move.
Also from review: the composer's own focus() on unlock and session switch
passes preventScroll, so a session switch cannot move the transcript through
the taller textarea's reveal chain.
The composer paints its draft in two layers — the textarea owns the value,
the selection and the caret, the backdrop paints every visible glyph — and
they had one scroll offset each, kept equal by a `scroll` listener. That
holds at rest and not in motion: a wheel gesture scrolls the textarea on the
compositor, the listener runs afterwards, and for those frames the caret sits
at the new offset with the words at the old one. Measured on a harness of the
same geometry, a 200px offset change separates caret from glyphs by ~200px
(chromium 203, firefox 202, WebKit 203) until a later frame — the caret
flying out of its own text when a user swipes a long draft quickly.
Both layers now ride one scrollport: `[data-input-scroll]` carries the
14-line cap, the auto-grow stack inside it is as tall as the whole draft, and
the textarea holds no scrollable overflow of its own. The browser applies one
offset to both layers in the same frame, so the coupling is structural rather
than maintained. The backdrop's trailing-line sentinel and the cross-engine
wrap-width premise go with the mirror: the layers now share a containing
block, which closes the WebKit 768-against-776 gap by construction.
Public snapshot state stays in the store engine's plain-data vocabulary
(immer drafts reject Sets without the MapSet plugin, which stays off):
manager/service/contract carry readonly SessionId[] in Host order, and
the tree derivations build their own transient Set — the
expandedProjects pattern. Membership-unchanged installs still keep the
array reference for Object.is short-circuits.
WorkspaceListState gains archivedSessionIds (ReadonlySet, replaced only
on membership change), installed as full snapshots from the list
baseline, the unary echo, and the changed frame. Archiving the current
session clears the selection into the New Session view state. Test
doubles (test-runtime, fake APIs, fixture client) follow the widened
IWorkspaces/IApiClient faces.
Review caught a real divergence the earlier measurements missed: mirroring
an offset is only correct while both layers can reach it, and for a draft
ending in a newline the backdrop could not.
A textarea reserves a line box for the caret after a final newline.
`white-space: pre-wrap` collapses a text node's trailing newline and
generates none. So a draft ending in a newline made the backdrop exactly one
line shorter than the textarea — measured 628 against 652 — and the mirrored
assignment clamped, leaving the glyphs one line behind the caret at the very
bottom of the draft.
The backdrop now carries the same trailing-line sentinel the mirror div has
carried all along: its content is the decoration walk plus one newline. The
same pre-wrap collapse absorbs it when the draft does not end in a newline,
so it costs no height in the ordinary case, and it supplies the missing line
box when it does. Verified in isolation first: a bare pre-wrap div measures
180/180/198 against a textarea's 180/198/216 for zero, one and two trailing
newlines, and 180/198/216 with the sentinel.
Coverage for the shape that exposed it: the browser scenario asserts the two
extents are equal before asserting the glyphs reach the end, observing each
layer's maximum by asking for an impossible offset and reading back the
clamp rather than computing it from scrollHeight, and the golden records the
relation. The unit spec pins the backdrop's text as the draft plus exactly
one newline. Removing the sentinel fails both, the e2e with the same 628
against 652.
The scrollbar-gutter half of the same review point does not reproduce here:
both layers measure clientWidth 776 against a border box of 776 while the
draft overflows, so this engine's textarea scrollbar is an overlay and takes
no width out of the wrap.
The first version coupled the layers from two places: a `scroll` listener
and a layout effect keyed on the committed draft. Mutation-testing each
hook alone against the built client shows the effect never fires the only
assignment that matters — with just the layout effect disabled the browser
scenario stays green, while disabling just the listener fails it.
Both premises behind the effect were wrong. Typing scrolls the caret into
view, which is an ordinary `scroll`. A draft that shrinks past the current
offset clamps both layers to the same maximum, because their extents are
equal — measured in chromium at 964/964, 1012/1012, 844/844 and 820/820 for
plain, soft-wrapped, unbreakable-run and highlighted drafts — and the
textarea's clamp fires `scroll` too.
The hazard the effect was imagined to cover does not exist either: React
replacing every child of the backdrop when the decoration set changes shape
preserves `scrollTop` (measured: 300 stays 300 through a full child
replacement), and the only replacement that zeroes it shrinks the content
below the offset, which is the clamp case already covered.
The e2e's edit case survives, retitled to say what it actually pins: that
typing is not a separate case needing its own mirror. The unit spec now
asserts the backdrop tracks a second move back to the top, which a one-shot
mirror would fail.
A composer draft past the 14-line cap could not be scrolled: the caret and
the selection moved, but the words stayed frozen at line 1, so the tail of
anything longer than the cap was unreachable while writing it.
The composer paints its text in two stacked layers. The textarea owns the
value, the selection and the caret but renders its own glyphs transparent;
every visible character is painted by the decoration backdrop beneath it,
which also carries the claim-token highlight, the chips and the ghost hint.
The backdrop is `inset: 0; overflow: hidden` — clipped, not scrolled — and
nothing linked its offset to the textarea's. Below the cap both layers rest
at 0, which is why the defect hid behind every short-draft screenshot and
fixture.
InputBar now mirrors the textarea's scrollTop onto the backdrop, from a
`scroll` listener (every gesture and every caret-driven scroll) and from a
layout effect keyed on the committed draft (an edit reflows both layers
without necessarily firing a scroll event).
Scrolling is layout, so jsdom cannot show this: the unit spec stubs both
offsets and proves the mirroring paths run, while a new browser scenario
measures the user-visible fact against the built client with a DOM Range
over the backdrop's own text — after a wheel gesture over a 40-line draft
the last line is on screen and the first has scrolled out. Confirmed both
directions: with the mirroring reverted and the packages rebuilt, the
golden reads `last draft line is on screen: false` while `textarea moved:
true`.
Replace the surface-ordered fold with a log-ordered human transcript:
append-origin surface events at their own log positions plus one marker per
landed compaction checkpoint. Command folding, the tool-call index, and the
rev-keyed memo carry over unchanged.
Removes foldDegraded, the padding sentinels, baseSeq, and degradedSeqs() --
they existed only to satisfy the core fold's seq === index assertion. That
also closes the pagination hole A1 exposed: a page can carry a checkpoint
whose shadowed range fell outside the window, and nothing resolves
surfaceOp.start anymore.
Unify the /plan claimed hint with the plan placeholder through a locale
namespace, localize slash menu group titles, replace the PermissionSelect
native select with the Menu primitive, add a goal pause verb chain, clamp
anchored popups to the viewport with scroll-into-view and outside-dismiss,
and fix onPasteUpgrade insertedRange to account for the chip trailing gap.
Shared-surface conflicts resolve as unions: the fixture serves all five
projection keys (title/todos/permissions/plan/goal) with the /permission
and /plan command mirrors side by side, the connection specs assert the
five-key baseline and the shifted approval/question replay indices, and
the cli roster/deps, tsconfig aggregate, and README allowlist carry both
lines' rows. Plan-side content lands verbatim from master.
One end-state consolidation both branches half-did: with questions
(ui-question) and approvals (ApprovalPanel) each owning a composer
takeover, PendingCard retires outright — ChatView renders no pending
placeholder, the card component and its specs go, and both README halves
state the takeover-only contract.