The check added last commit derived its elevated set from the sheets that
already rebind, which cannot catch the omission it targets: such a set only
confirms what someone already remembered, and a surface nobody has rebound
yet defines itself as unelevated. Review found the case that proves it —
TodoPanel scrolls in .list on a --dsw-specific-tip card, the same dark rung
as the menu surface, unrebound and with the derived check green.
Resolves the set from the palette's own dark elevation ladder instead: the
surface tokens whose dark value lands on bg-layer-2 or bg-layer-3, which is
the step the l1/l2 split encodes. A new palette token on an elevated rung is
in scope the moment it is defined.
Scope is by token family rather than geometry: only --dsw-alias-bg-* and
--dsw-specific-* name a surface. The button, interactive, and markdown
families reach the same rungs while naming a control or an inline span that
no scroll container renders a bar against, and shape cannot separate them
since a floating button carries a radius, a shadow, and a fixed size —
ChatView's .toBottom pill was the false positive that showed this.
Adds the missing TodoPanel rebind. Mutation-checked all four rebinds in
turn: each is named with its surface. The palette anchoring has its own
control — narrowing the family pattern turns it red on --dsw-specific-menu.
test:web ran build:web alone, which does not rebuild UI plugin client
bundles. Plugin CSS reaches the browser through packages/client/*/lib/
client.js, not apps/web/dist, so a changed *.module.css served its
previous bundle: the run exercised stale CSS and a removed declaration
still passed. That is how I first mistook a valid gutter test for a
vacuous one.
Root build already covers packages/*/*, so running it first is enough;
check-all already ordered build before build:web, so CI was never
exposed. Only the local script was, which is where a stale-bundle pass is
most likely to be believed.
Verified against the situation it fixes: mutate the source, rebuild the
bundle, restore the source, and the artifact is left without the
declaration while the source has it. Under the old script the run tested
that artifact; under the new one the artifact is rebuilt first (grep goes
0 to 1) and the scrollbar spec passes. The nine failing web files are the
pre-existing aria-golden set from f2c004524, unchanged by this.
Review found three scroll containers sitting on surfaces the rebinding
contract covers, none of which rebound: ui-primitives' shared Menu card
on --dsw-specific-menu (the surface PopupSelectView already rebinds for),
and the composer input and question composer cards, both on
--dsw-specific-input-major. Each rendered the l1 thumb, which differs
from l2 only in the dark palette and only on that surface, so a
light-palette screenshot and a code read both look correct.
Adds the mechanical check that would have caught them instead of leaving
it to inspection: a sheet that scrolls somewhere and paints a known
elevated surface somewhere must rebind. The elevated set is derived from
the sheets that already rebind, since a rebinding rule paints the surface
whose elevation it declares, so a new elevated surface joins the set by
rebinding rather than by anyone updating a list. Surface-level rather than
element-level because the card and the descendant that scrolls are
separate rules and CSS text does not say which contains which. Verified by
reverting each of the three fixes in turn: the check names the sheet and
the surface every time.
Also commits snapshots/sidebar-scrollbar/geometry.expected.md, the
resolved scrollbar style and geometry in both palettes. The aria goldens
the other web scenarios commit cannot carry a CSS-only change, since it
alters no DOM and no accessible name and leaves their trees
byte-identical. Absolute coordinates stay out: they track font metrics and
the laid-out sidebar width, so committing them would document the platform
and force a per-platform re-record.
The e2e measured the reserved band but never the symptom the change is
named for. Headless chromium defaults to an overlay scrollbar, which is
the configuration where a bar can cover row content at all, so the
scenario already ran in the right mode: against clean master the band is
0 and the bar covers 7px of the relative time.
Adds timeCoveredBy, the overlap between the relative time's right edge
and the range the bar occupies, taking the bar's width from the sheet
where it applies and from the UA's overlay width otherwise. Assuming 0
there would report no occlusion in precisely the state that has it.
Keeps the band assertion rather than replacing it: the two catch
different regressions. Removing only scrollbar-gutter leaves
timeCoveredBy at 0, because the bar is then 8px and the row's right
padding is also 8px, so it abuts the timestamp without covering it.
Removing the pseudo-element width as well is what produces the overlap.
Each was mutation-checked with the other assertions in its test silenced.
Records in the note that the gutter and the ::-webkit-scrollbar width are
jointly necessary against an overlay bar, measured by deleting each from
the live cascade with the other in force: either alone drops the band
from 8 to 0.
