A dirty widget is asked again in the box its parent asked it in, and then
again in the box its parent chose from that answer. The second ask was
skipped whenever the two boxes were the same *length*, which is not the same
question: an offer as long as the final box but somewhere else is a different
box. `d3b0ebf` already compared whole boxes for `parent_must_place` and left
this one a length comparison, so the two halves of one decision disagreed.
It shows on a region node, which draws the box it drew in into its own move
entry. A scroll inside a scrolled span is offered the outer scroll's whole
viewport and placed 24px above it, the height of the sized child the outer
scroll snaps to the end of; redrawing only its text left it at the offer and
24px too low. `tests/cases/unsettled.rs` had that five-widget tree ignored as
a known defect and now runs it.
`px_region` names the walk both comparisons and `window_region` were writing
out.
Checked: fmt, clippy, 80 tests, the release oracle at 100 seeds, all fifteen
shrinker cases at 400 seeds of depth 5, and `tabs`, `view`, `minimal`,
`text`, `random` plus the tab replay byte-identical at 1920x1200 against
`98d4e98`. The `many` fixture's twenty-five counters are unchanged.
Fixed with it, from the handoff's unreduced leads: shrinker seeds 174 and 175
on `repaint-some` and seed 2 on `region-node`, and oracle seeds 18 and 190 at
depth 6. Still failing: shrinker seed 288 on `region-node`, and oracle seed
326 at depth 6, which reduces to 43 widgets around two `Branch`es and is not
this.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The oracle grew its trees from a seed and the shrinker grew its own, with
every scenario written out on each side. So a failure the oracle found could
not be handed to the shrinker: there was no tree to pass it, only a seed, and
a seed cannot be made smaller. The shrinker could only grow its own trees and
hope to meet the same shape, which it does not -- 20,000 of its trees never
reproduced what the oracle's seed 18 shows at depth 6.
`iris::random` now answers with a `Plan`: `plan(seed, depth, &edits)` draws one
out of the random stream and `build(rsc, &plan)` makes the widgets, where
`grow` did both at once. Every draw happens in the order it always has, so a
seed still means the tree it meant -- checked by running the oracle at 1000
seeds of depth 6 before and after and getting the same three failures with the
same boxes. `Plan::smaller` reduces one, `Plan::edited` applies an `Edits` to a
tree that already exists, and `tests/scenario/` holds the fifteen cases both
rigs now run over the same trees.
A span keeps the order it holds its children in apart from the children
themselves, so detaching, attaching and reordering leave the widgets made in
the same order and two builds still line up index for index. `Tree::detached`
is gone: `Spanned::spares` is everything made for a span that it does not
hold, which is what both of those were.
`tests/cases/plan.rs` pins the three properties the rest rests on: editing a
plan is growing one with those edits, every simplification is smaller than
what it came from, and reducing ends. The second caught this change's own
defect, where dropping a side of a `Branch` duplicated another and grew the
tree by four widgets.
What it found, on its first run: `SHRINK_SEED=18 SHRINK_DEPTH=6
SHRINK_CASE=repaint-some` reduces 277 widgets to 5. A scroll inside a scroll,
the inner one owning a movable region, and only the text at the bottom marked
for redraw -- and the span lands 24px out, which is exactly the sized child's
height. `git bisect` names `95fb4f9`, where `Masked` began reporting its box
rather than its inner's size, so what the outer scroll is told its content
measures now depends on whether the inner subtree was redrawn this frame.
`tests/cases/unsettled.rs` has it written out, ignored until it is fixed.
Checked: fmt, clippy over all targets with -D warnings, the workspace tests
(79 + 11 + 15, one ignored for the defect above), and the 100-seed oracle over
all fifteen cases at depth 4. The shrinker at 400 seeds of depth 5 now fails,
which it did not before running the oracle's trees and cases: seeds 2 and 288
on region-node and 174 and 175 on repaint-some are unreduced leads.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
`UiScalar` was `Len` without the `leftover` weight, which is the separation
canonical `main` already had as `Len` beside `LayoutLen` and this branch
collapsed. It is needed back for the queued clamp: a cap may not contain a
share, because a cap has to read the report a rule otherwise makes moot, and
a share puts the container's division into the same equation -- two
self-consistent assignments, which is the multiple-fixed-point failure
generated seed 13 punished for orthogonal sizing. `min(report, cap)` is not
a `LayoutLen` either: it is a sum of parts, and the smaller of two of them
is not one.
So `UiScalar` is `Len`, what was `Len` is `LayoutLen`, and the two say in
their docs which is which: a `Len` is pixels plus a fraction of a box -- a
position being the length from the box's start, which is why a span is two
of them -- and a `LayoutLen` is a `Len` plus a claim only a container
dividing its room can answer. `From<Len> for LayoutLen` is the one-way step
between them.
Names only; the shader's `UiScalar` is renamed with them. Checked: fmt,
clippy, 105 tests, and `tabs`, `minimal`, `view`, `text` and `random`
byte-identical at 1920x1200.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
A span is as long across itself as its longest child, unless a rule beside it
already says how long it is -- and then reading the children answers nothing
and only makes its size depend on theirs. `OrthoSize::Full` was that second
case written twice, once as an enum on the span and once as the rule that
actually decides; `Painter::ruled` lets the span ask which it is in. The
widget under a rule still does not learn what the rule says, only that its
answer for that axis is not wanted.
The fuzzers grow, lay out and drop a tree within one seed, so the seeds share
nothing and take a thread each, one short of every core. Measured here: the
generated oracle's hundred seeds went from 68 s to 10 s, and a shrinker case
at 300 seeds from 18 s to 3.5 s. A seed that fails still shrinks and panics
on its own thread, and `std::thread::scope` carries that out.
The shrinker now allows the two steps the oracle already did -- the deeper
trees these grow reach a second composition, and a step is a thousandth of a
pixel.
Checked: fmt, clippy, 102 tests, all five shrinker cases at 300 seeds, 100
generated seeds, and five examples byte-identical at 1920x1200.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Eleven `tests/*.rs` were eleven binaries, each linking the whole graph --
`wgpu` and all -- to run a handful of cases. They are modules of one target
now, under `tests/cases/`, and `cargo test --test suite layout::` still picks
one out. The fuzzers and the `*_cost` measurements stay their own targets:
they are run on their own and want to be selectable without building the
rest.
`profile.test` takes `debug = "line-tables-only"`, which is what a backtrace
here actually reads; the type and variable information was the bulk of what
the linker was writing.
Measured on this machine, rebuilding `iris`'s test targets after a change to
the crate: 14.3 s before, 9.8 s with one target, 7.7 s with both. `target/`
went from 45 GB to 13 GB. The suite still passes 102 tests, and the binary
still carries `.debug_line`.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>