Fix block child spacing

library/src/layout/container.rs

@@ -362,6 +362,10 @@ impl Layout for BlockElem {
             pod.size.x = size.x;
             pod.expand = expand;
 
+            if expand.y {
+                pod.full = size.y;
+            }
+
             // Generate backlog for fixed height.
             let mut heights = vec![];
             if sizing.y.is_custom() {
@@ -375,6 +379,10 @@ impl Layout for BlockElem {
                     }
                 }
 
+                if let Some(last) = heights.last_mut() {
+                    *last += remaining;
+                }
+
                 pod.size.y = heights[0];
                 pod.backlog = &heights[1..];
                 pod.last = None;

tests/typ/layout/container.typ

@@ -10,7 +10,16 @@ Spaced \
 Apart
 
 ---
-// Test box sizing.
+// Test block sizing.
+#set page(height: 120pt)
+#set block(spacing: 0pt)
+#block(width: 90pt, height: 80pt, fill: red)[
+  #block(width: 60%, height: 60%, fill: green)
+  #block(width: 50%, height: 60%, fill: blue)
+]
+
+---
+// Test box sizing with layoutable child.
 #box(
   width: 50pt,
   height: 50pt,