Text boxes in a group: the topmost member takes the click

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

crates/layout/src/hit.rs

@@ -467,7 +467,7 @@ impl DocLayout {
     pub fn story_at(&self, page: usize, x: f32, y: f32) -> Option<StoryRef> {
         let p = self.pages.get(page)?;
         // A group's text boxes count as text boxes too (#6027).
-        // Topmost first, a text box on its own or one in a group alike.
+        // Topmost first, a text box on its own or one in a group alike (a group's last member is painted on top).
         let text_box = |behind: bool| {
             p.items.iter().rev().find_map(|it| {
                 let Placed::Object { rect, spin, text_box, wrap, group_boxes, .. } = it else { return None };
@@ -477,7 +477,11 @@ impl DocLayout {
                 let centre = Point::new(rect.x + rect.w / 2.0, rect.y + rect.h / 2.0);
                 let (ux, uy) = spin.unapply(centre.x, centre.y, x, y);
                 text_box.filter(|_| rect.contains(Point::new(ux, uy))).or_else(|| {
-                    group_boxes.iter().find(|(r, _)| Rect::new(rect.x + r.x, rect.y + r.y, r.w, r.h).contains(Point::new(x, y))).map(|(_, id)| *id)
+                    group_boxes
+                        .iter()
+                        .rev()
+                        .find(|(r, _)| Rect::new(rect.x + r.x, rect.y + r.y, r.w, r.h).contains(Point::new(x, y)))
+                        .map(|(_, id)| *id)
                 })
             })
         };

crates/layout/src/tests.rs

@@ -3992,6 +3992,36 @@ fn grouped_text_box_areas_turn_with_the_group_and_work_in_headers() {
     assert_eq!(l.header_footer_text_box_at(0, 150.0, 40.0), None, "the group's bar is not text");
 }
 
+/// #6027: where two text boxes of one group overlap, a click enters the one painted on top (the
+/// last member), in the body and in a header alike.
+#[test]
+fn click_in_overlapping_grouped_text_boxes_enters_the_top_one() {
+    let (low, top) = (3, 4);
+    let group = |rect| Placed::Object {
+        rect,
+        spin: Default::default(),
+        story: StoryRef::Part(1),
+        path: Path::top(0),
+        off: 0,
+        text_box: None,
+        wrap: Default::default(),
+        origin: Default::default(),
+        group_boxes: vec![(wordcraft_geom::Rect::new(0.0, 0.0, 100.0, 100.0), low), (wordcraft_geom::Rect::new(50.0, 50.0, 100.0, 100.0), top)],
+    };
+    let page = Page {
+        items: vec![group(wordcraft_geom::Rect::new(100.0, 100.0, 150.0, 150.0))],
+        header: vec![group(wordcraft_geom::Rect::new(100.0, 100.0, 150.0, 150.0))],
+        ..Default::default()
+    };
+    let l = DocLayout { pages: vec![page], ..Default::default() };
+    // Overlap (page 175, 175 is inside both boxes): the top box takes the click, and typing.
+    assert_eq!(l.story_at(0, 175.0, 175.0), Some(StoryRef::Part(top)));
+    assert_eq!(l.header_footer_text_box_at(0, 175.0, 175.0), Some(top));
+    // Outside the overlap each box still answers for itself.
+    assert_eq!(l.story_at(0, 110.0, 110.0), Some(StoryRef::Part(low)));
+    assert_eq!(l.story_at(0, 240.0, 240.0), Some(StoryRef::Part(top)));
+}
+
 #[test]
 fn deleted_float_leaves_no_wrap_area_without_markup() {
     crate::test_fonts();