Constrain offered boxes with independent widget size bounds

tests/scenario/mod.rs

@@ -200,8 +200,8 @@ fn mark(warm: &mut Harness, tree: &Tree, step: usize) {
 fn a_rule(rng: &mut Rng) -> SizeRule {
     let len = Len::px(20.0 + rng.below(180) as f32);
     match rng.below(4) {
-        0 => SizeRule::Max(len),
-        1 => SizeRule::Min(len),
+        0 => SizeRule::max(len),
+        1 => SizeRule::min(len),
         _ => LayoutLen::from(len).into(),
     }
 }
@@ -357,18 +357,7 @@ fn change(case: Case, warm: &mut Harness, tree: &mut Tree, plan: &Plan, rng: &mu
 /// buildable from what the failure printed.
 fn describe(id: WidgetId, h: &Harness) -> String {
     let rules = h.rsc.widgets().size_rules(id).clone();
-    // A bound prints as itself: a failure is reproduced from what it printed,
-    // and a rule shown as "no rule" cannot be written out again.
-    let rule = |r: SizeRule| match r {
-        SizeRule::Free => "-".into(),
-        SizeRule::Exact(len) => format!("{len}"),
-        SizeRule::Request(request) => format!("{request:?}"),
-        SizeRule::Min(min) => format!(">{}", LayoutLen::from(min)),
-        SizeRule::Max(max) => format!("<{}", LayoutLen::from(max)),
-        SizeRule::Clamp { min, max } => {
-            format!(">{}<{}", LayoutLen::from(min), LayoutLen::from(max))
-        }
-    };
+    let rule = |r: SizeRule| format!("{r:?}");
     let align = h.rsc.widgets().alignment(id);
     let side = |a: AxisAlign| {
         if a == AxisAlign::NEG {