Files
iris/tests/scenario/mod.rs
T
iris-ai 2ed5503717 Recompose retained frames exactly and preserve text width validity
Keep each widget's original local frame and replay the same composition
order on reuse. Remove inverse region remapping, including its fixed-frame
fallback that forced otherwise valid subtrees to draw again.

Require exact pixel-region equality in the shared generated oracle. Check
primitive and mask geometry as well as draw reuse when fixed frames resize.
Publish text's retained line-break range, with no upper bound when there
are no soft breaks, and cover widening, explicit newlines, and empty text.

Compared with efb416b, the depth-8 diagnostic rig performs 7-9% fewer widget
evaluations in the affected phases. Uninstrumented release runs use 3.5%
fewer instructions for size changes and 5.0% fewer for resize. Repaint and
scroll use 0.7% and 0.6% more instructions. Container updates remain substantially more expensive than the e44dea3 baseline;
this is still an experimental continuation, not a production replacement.
2026-09-17 15:11:03 -04:00

439 lines
15 KiB
Rust

//! The scenarios both fuzzers run, over the tree a [`Plan`] describes.
//!
//! One implementation rather than two. 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. Both take a plan now, so whatever finds a counterexample can also
//! reduce it.
//!
//! Each target compiles this for itself, so what only one of them calls is
//! dead code in the other.
#![allow(dead_code)]
use iris::harness::Harness;
use iris::prelude::*;
use iris::random::{Aligns, Edits, Kind, Lens, Plan, Rng, SpanEdit, Tree, build};
use std::collections::HashMap;
/// A seed per thread but one, since a seed grows, lays out and drops its tree
/// alone. A failing seed still shrinks and panics on its own thread.
pub fn over_seeds(seeds: Vec<u64>, run: impl Fn(u64) + Sync) {
let threads =
std::thread::available_parallelism().map_or(1, |n| n.get().saturating_sub(1).max(1));
let chunk = seeds.len().div_ceil(threads).max(1);
std::thread::scope(|scope| {
for part in seeds.chunks(chunk) {
let run = &run;
scope.spawn(move || part.iter().for_each(|&seed| run(seed)));
}
});
}
pub fn env<T: std::str::FromStr>(name: &str, fallback: T) -> T {
std::env::var(name)
.ok()
.and_then(|v| v.parse().ok())
.unwrap_or(fallback)
}
/// The window a tree is grown in, and the one a resize takes it to.
const OUTER: (f32, f32) = (1920.0, 1200.0);
const INNER: (f32, f32) = (640.0, 900.0);
const STILL: (f32, f32) = (900.0, 1200.0);
/// A way of changing what a span holds. Each is a shape worth its own case:
/// taking a child out of the middle is not the same as emptying a span, and
/// adding one is not the same as adding three.
#[derive(Clone, Copy, Debug, PartialEq)]
pub enum Shuffle {
/// Every other child, so what is left is interleaved with what went.
EveryOther,
/// Everything but the first, which is the last step before empty.
AllButFirst,
/// Three more on the end at once.
AddThree,
/// The first out and three more on, so the count moves both ways.
SwapForThree,
/// One out of the middle and one on the end.
TradeOne,
}
impl Shuffle {
fn of(self, grown: usize) -> SpanEdit {
let all = |step: usize, from: usize| (from..grown).step_by(step).collect();
match self {
Self::EveryOther => SpanEdit {
detach: all(2, 0),
attach: 0,
},
Self::AllButFirst => SpanEdit {
detach: all(1, 1),
attach: 0,
},
Self::AddThree => SpanEdit {
detach: Vec::new(),
attach: 3,
},
Self::SwapForThree => SpanEdit {
detach: vec![0],
attach: 3,
},
Self::TradeOne => SpanEdit {
detach: vec![grown / 2],
attach: 1,
},
}
}
}
/// What a warm tree is put through before it is compared with a cold one
/// grown the way it was left.
#[derive(Clone, Copy, Debug, PartialEq)]
pub enum Case {
/// Nothing changes, so no box may either. What this exercises is the
/// order a frame settles a dirty set in.
Repaint,
/// Every fifth widget rather than all of them: marking all of them
/// redraws the whole tree, which is a cold start reached the long way,
/// where the mixed case leaves a redrawn subtree beside a retained one.
RepaintSome,
Resize,
ResizeRepaint,
/// A resize and then a size change, so a retained answer is asked to
/// survive two different kinds of invalidation in a row.
ResizeSize,
/// A few declared sizes.
Size,
/// Every declared size at once, so every reader of a size has a changed
/// descendant in the same frame and the whole dirty set settles together.
EverySize,
Align,
/// Giving a widget a movable region of its own, or taking it away, is a
/// structural change: every primitive under it changes which chain
/// resolves it.
RegionNode,
/// The same children in a different order, which moves every one of them
/// without changing what any of them is.
Reorder,
Shuffle(Shuffle),
}
pub const ALL: [Case; 15] = [
Case::Repaint,
Case::RepaintSome,
Case::Resize,
Case::ResizeRepaint,
Case::ResizeSize,
Case::Size,
Case::EverySize,
Case::Align,
Case::RegionNode,
Case::Reorder,
Case::Shuffle(Shuffle::EveryOther),
Case::Shuffle(Shuffle::AllButFirst),
Case::Shuffle(Shuffle::AddThree),
Case::Shuffle(Shuffle::SwapForThree),
Case::Shuffle(Shuffle::TradeOne),
];
impl Case {
/// The name `CASE` selects it by, and the one a failure prints.
pub fn name(self) -> &'static str {
match self {
Self::Repaint => "repaint",
Self::RepaintSome => "repaint-some",
Self::Resize => "resize",
Self::ResizeRepaint => "resize-repaint",
Self::ResizeSize => "resize-size",
Self::Size => "size",
Self::EverySize => "every-size",
Self::Align => "align",
Self::RegionNode => "region-node",
Self::Reorder => "reorder",
Self::Shuffle(Shuffle::EveryOther) => "shuffle-every-other",
Self::Shuffle(Shuffle::AllButFirst) => "shuffle-all-but-first",
Self::Shuffle(Shuffle::AddThree) => "shuffle-add-three",
Self::Shuffle(Shuffle::SwapForThree) => "shuffle-swap-for-three",
Self::Shuffle(Shuffle::TradeOne) => "shuffle-trade-one",
}
}
pub fn named(name: &str) -> Option<Self> {
ALL.into_iter().find(|case| case.name() == name)
}
/// Grown in the first, compared in the second.
fn window(self) -> ((f32, f32), (f32, f32)) {
match self {
Self::Resize | Self::ResizeRepaint | Self::ResizeSize => (OUTER, INNER),
_ => (STILL, STILL),
}
}
}
fn mark(warm: &mut Harness, tree: &Tree, step: usize) {
for &id in tree.ids.iter().step_by(step) {
warm.rsc.widgets_mut().get_dyn_mut(id);
}
}
fn a_len(rng: &mut Rng) -> Option<LayoutLen> {
Some(LayoutLen::px(20.0 + rng.below(180) as f32))
}
fn resize_one(warm: &mut Harness, tree: &Tree, idx: usize, rng: &mut Rng) -> Lens {
let lens = [a_len(rng), a_len(rng)];
warm.rsc
.widgets_mut()
.set_size_rules(tree.sized[idx], lens[0], lens[1]);
lens
}
fn realign_one(warm: &mut Harness, tree: &Tree, idx: usize, rng: &mut Rng) -> Aligns {
let side = |rng: &mut Rng| match rng.below(4) {
0 => None,
1 => Some(AxisAlign::NEG),
2 => Some(AxisAlign::CENTER),
_ => Some(AxisAlign::POS),
};
let align = [side(rng), side(rng)];
let id = tree.aligned[idx];
for (axis, align) in [Axis::X, Axis::Y].into_iter().zip(align) {
warm.rsc
.widgets_mut()
.set_alignment(id, axis, align.unwrap_or_default());
}
align
}
/// Every span's children in a different order, said both to the warm tree and
/// to the plan the cold one is grown from.
fn reorder(warm: &mut Harness, tree: &Tree, plan: &Plan) -> Plan {
for span in &tree.spans {
let children = &mut warm.rsc[span.id].children;
if !children.is_empty() {
children.rotate_left(1);
}
}
let mut out = plan.clone();
out.walk_mut(&mut |node| {
if let Kind::Span { order, .. } = &mut node.kind
&& !order.is_empty()
{
order.rotate_left(1);
}
});
out
}
/// Applies `shuffle` to every third span. What it takes out is given back to
/// the span's spares: the last share of a widget must outlive the comparison,
/// or its id is handed to something else and the two trees stop lining up.
fn reshuffle(warm: &mut Harness, tree: &mut Tree, shuffle: Shuffle) -> HashMap<usize, SpanEdit> {
let mut edits = HashMap::new();
for (idx, span) in tree.spans.iter_mut().enumerate().step_by(3) {
let edit = shuffle.of(span.grown);
let mut take = edit.detach.clone();
take.sort_unstable();
let children = &mut warm.rsc[span.id].children;
// Highest first, so an index means the same child however many of its
// neighbours are going too.
for j in take.into_iter().rev() {
if j < children.len() {
span.spares.push(children.remove(j));
}
}
let attach = edit.attach.min(span.spares.len());
let moved: Vec<_> = span.spares.drain(..attach).collect();
warm.rsc[span.id].children.extend(moved);
edits.insert(idx, edit);
}
edits
}
/// Changes the warm tree and answers with the plan a cold tree grown that way
/// comes from. Each arm settles its own frame, so a case that changes nothing
/// does not get a second one that could settle what the first left.
fn change(case: Case, warm: &mut Harness, tree: &mut Tree, plan: &Plan, rng: &mut Rng) -> Plan {
let some_sizes = |warm: &mut Harness, tree: &Tree, rng: &mut Rng| {
let mut sizes = HashMap::new();
for _ in 0..4 {
if tree.sized.is_empty() {
break;
}
let idx = rng.below(tree.sized.len());
sizes.insert(idx, resize_one(warm, tree, idx, rng));
}
sizes
};
let edits = match case {
Case::Resize => return plan.clone(),
Case::Repaint | Case::ResizeRepaint => {
mark(warm, tree, 1);
warm.frame();
return plan.clone();
}
Case::RepaintSome => {
mark(warm, tree, 5);
warm.frame();
return plan.clone();
}
Case::Reorder => {
let out = reorder(warm, tree, plan);
warm.frame();
return out;
}
Case::Size | Case::ResizeSize => Edits {
sizes: some_sizes(warm, tree, rng),
..Default::default()
},
Case::EverySize => Edits {
sizes: (0..tree.sized.len())
.map(|idx| (idx, resize_one(warm, tree, idx, rng)))
.collect(),
..Default::default()
},
Case::Align => Edits {
aligns: (0..tree.aligned.len())
.step_by(3)
.map(|idx| (idx, realign_one(warm, tree, idx, rng)))
.collect(),
..Default::default()
},
Case::RegionNode => {
let mut nodes = HashMap::new();
for idx in (0..tree.nodes.len()).step_by(2) {
let id = tree.nodes[idx];
let take = !warm.rsc.widgets().is_region_node(id);
warm.rsc.widgets_mut().set_region_node(id, take);
nodes.insert(idx, take);
}
Edits {
nodes,
..Default::default()
}
}
Case::Shuffle(shuffle) => Edits {
spans: reshuffle(warm, tree, shuffle),
..Default::default()
},
};
warm.frame();
plan.edited(&edits)
}
/// What a widget was configured with, so a tree a fuzzer found can be written
/// out by hand. A failure is a lead; the fast test that replaces it has to be
/// buildable from what the failure printed.
fn describe(id: WidgetId, h: &Harness) -> String {
let rules = h.rsc.widgets().size_rules(id);
let rule = |r: SizeRule| match r.exact() {
Some(len) => format!("{len}"),
None => "-".into(),
};
let align = h.rsc.widgets().alignment(id);
let side = |a: AxisAlign| {
if a == AxisAlign::NEG {
"neg".into()
} else if a == AxisAlign::CENTER {
"mid".into()
} else if a == AxisAlign::POS {
"pos".into()
} else {
format!("{:.2}", a.rel())
}
};
// A rule and an alignment are properties of whatever carries them, so
// they print with that widget rather than as widgets of their own.
let mut out = describe_widget(id, h);
if (rules.x, rules.y) != (SizeRule::Free, SizeRule::Free) {
out += &format!("[x:{},y:{}]", rule(rules.x), rule(rules.y));
}
if align != RegionAlign::default() {
out += &format!("@{},{}", side(align.x), side(align.y));
}
out
}
fn describe_widget(id: WidgetId, h: &Harness) -> String {
let label = h.rsc.widgets().label(id).to_string();
let Some(widget) = h.rsc.widgets().get_dyn(id) else {
return label;
};
let any: &dyn std::any::Any = widget;
if let Some(w) = any.downcast_ref::<Span>() {
let sign = if w.dir.sign == Sign::Neg { "-" } else { "+" };
return format!(
"Span{{dir:{:?}{sign},gap:{},n:{}}}",
w.dir.axis,
w.gap,
w.children.len()
);
}
if let Some(w) = any.downcast_ref::<Pad>() {
let p = &w.padding;
return format!(
"Pad{{l:{},r:{},t:{},b:{}}}",
p.left, p.right, p.top, p.bottom
);
}
if let Some(w) = any.downcast_ref::<Stack>() {
return format!("Stack{{n:{}}}", w.children.len());
}
label
}
/// Runs `case` on the tree `plan` describes, warm and cold, and says where
/// the two disagree. `seed` chooses only the values a case picks at random,
/// so one plan under one case is one comparison however it was reached.
pub fn diverges(plan: &Plan, case: Case, seed: u64) -> Option<String> {
let (start, end) = case.window();
let mut warm = Harness::new(start);
let (root, mut tree) = build(&mut warm.rsc, plan);
warm.state.root = Some(root);
// The frame that makes it warm: without it nothing is retained and the
// comparison is two cold starts agreeing with each other.
warm.frame();
if start != end {
warm.resize(end);
warm.frame();
}
let cold_plan = change(case, &mut warm, &mut tree, plan, &mut Rng::new(seed));
let mut cold = Harness::new(end);
let (root, cold_tree) = build(&mut cold.rsc, &cold_plan);
cold.state.root = Some(root);
cold.frame();
let mut drawn = 0;
for (i, (&w, &c)) in tree.ids.iter().zip(&cold_tree.ids).enumerate() {
let (got, want) = (warm.region(&w), cold.region(&c));
drawn += got.is_some() as usize;
if got == want {
continue;
}
// Where two trees disagree is rarely where the cause is, so the
// ancestry comes with it, marking the widgets that own a region.
let mut chain = Vec::new();
let mut at = Some(w);
while let Some(id) = at {
let active = &warm.render.active[&id];
let node = match active.move_idx == active.parent_move {
true => "",
false => "*",
};
chain.push(format!("{}{node}", describe(id, &warm)));
at = active.parent;
}
return Some(format!(
"widget {i}\n warm {got:?}\n cold {want:?}\n {}",
chain.join(" < ")
));
}
match drawn {
0 => Some("nothing was drawn".into()),
_ => None,
}
}