#504: test that the Backstage side menu edge is not a resize handle

The File side menu is a fixed 200-point panel, but egui left it resizable, so hovering its right edge drew a resize line and showed a resize cursor that did nothing. The test hovers the edge and checks the pointer is not a resize cursor. Without the fix it reports ResizeEast.

crates/ui-egui/src/backstage.rs

@@ -736,6 +736,37 @@ mod tests {
         }
     }
 
+    /// Regression test for #504: the side menu is a fixed 200 points wide, but egui drew a resize
+    /// line and showed a resize pointer on its right edge that did nothing.
+    #[test]
+    fn the_side_menu_edge_is_not_a_resize_handle() {
+        let mut app = WordApp::new(wordcraft_engine::Session::new(wordcraft_doc::Document::new()), Services::default());
+        app.ui.language = "en".into();
+        app.ui.backstage = true;
+        let ctx = egui::Context::default();
+        let edge = egui::pos2(200.0, 400.0);
+        for frame in 0..8 {
+            let mut input = egui::RawInput {
+                time: Some(f64::from(frame) * 0.1),
+                screen_rect: Some(egui::Rect::from_min_size(egui::pos2(0.0, 0.0), egui::vec2(1440.0, 900.0))),
+                ..Default::default()
+            };
+            if frame > 0 {
+                input.events.push(egui::Event::PointerMoved(edge));
+            }
+            let mut out = ctx.run_ui(input, |ui| {
+                app.logic(&ctx.clone());
+                app.ui(ui);
+            });
+            out.textures_delta.clear();
+            if frame > 2 {
+                assert!(app.ui.backstage, "File is open");
+                let cursor = format!("{:?}", out.platform_output.cursor_icon);
+                assert!(!cursor.starts_with("Resize"), "frame {frame}: the menu edge shows a resize pointer ({cursor})");
+            }
+        }
+    }
+
     /// #2938: opening a deleted file from Recent keeps File open and reports the error instead of
     /// closing it on a greyed-out window.
     #[test]

crates/ui-egui/src/previews.rs

@@ -695,6 +695,83 @@ mod tests {
         assert!(loaded.len() <= 2, "previewing loaded {loaded:?}");
     }
 
+    /// A window whose Styles gallery lists `style` first: runs the gallery for a few frames and
+    /// returns the painted shapes of the last one and every texture picture uploaded on the way.
+    fn run_gallery(mut doc: Document, style: wordcraft_doc::styles::Style) -> (Vec<egui::epaint::ClippedShape>, Vec<egui::ColorImage>) {
+        // Only the style under test is in the gallery.
+        for other in &mut doc.styles.styles {
+            other.quick = false;
+        }
+        doc.styles.upsert(style);
+        let mut app = WordApp::new(wordcraft_engine::Session::new(doc), Default::default());
+        app.ui.language = "en".into();
+        let ctx = egui::Context::default();
+        let mut shapes = Vec::new();
+        let mut images = Vec::new();
+        for frame in 0..6 {
+            let input = egui::RawInput {
+                time: Some(f64::from(frame) * 0.1),
+                screen_rect: Some(Rect::from_min_size(pos2(0.0, 0.0), vec2(800.0, 200.0))),
+                ..Default::default()
+            };
+            let mut out = ctx.run_ui(input, |ui| {
+                ui.add_space(20.0);
+                style_gallery(&mut app, ui, &json!({}));
+            });
+            for (_, deltas) in out.textures_delta.set.drain() {
+                for delta in deltas {
+                    if let (None, egui::ImageData::Color(img)) = (delta.pos, &delta.image) {
+                        images.push(egui::ColorImage::clone(img));
+                    }
+                }
+            }
+            out.textures_delta.clear();
+            shapes = out.shapes;
+        }
+        (shapes, images)
+    }
+
+    fn gallery_style(name: &str) -> wordcraft_doc::styles::Style {
+        wordcraft_doc::styles::Style { id: "Backfill".into(), name: name.into(), quick: true, priority: Some(0), ..Default::default() }
+    }
+
+    /// Regression test for #2: a style gallery label longer than its tile was painted at full width
+    /// and ran into the neighbouring tiles; it is now cut with an ellipsis to fit the tile.
+    #[test]
+    fn a_long_style_name_is_truncated_to_its_tile() {
+        let name = "An extraordinarily long custom style name that cannot fit a tile";
+        let (shapes, _) = run_gallery(Document::new(), gallery_style(name));
+        let label = shapes
+            .iter()
+            .find_map(|s| match &s.shape {
+                egui::Shape::Text(t) if t.galley.job.text == name => Some(t),
+                _ => None,
+            })
+            .expect("the long style's label is painted");
+        // A tile is 74 points wide.
+        assert!(label.galley.size().x <= 74.0, "the label is {} points wide, wider than its 74-point tile", label.galley.size().x);
+        assert!(label.galley.elided, "the label is cut short with an ellipsis");
+    }
+
+    /// Regression test for #2: a style whose hanging indent is larger than its left indent previewed
+    /// with its first line starting off the tile's left edge; the first line now starts at the edge.
+    #[test]
+    fn a_hanging_indent_style_previews_from_the_tile_edge() {
+        let mut style = gallery_style("Hanging");
+        style.para.indent_left = Some(0.0);
+        style.para.indent_first = Some(-36.0);
+        let (_, images) = run_gallery(Document::new(), style);
+        // The style is the only one in the gallery: its preview is the picture of a tile's size (the other upload is egui's font texture).
+        let preview = images.iter().find(|i| (200..300).contains(&i.size[0]) && (20..60).contains(&i.size[1])).expect("the preview is rendered");
+        let [w, h] = preview.size;
+        let inked: Vec<bool> = (0..w).map(|x| (0..h).any(|y| preview.pixels.get(y * w + x).is_some_and(|p| p.a() > 0 && p.r() < 160))).collect();
+        let first = inked.iter().position(|&i| i).expect("the preview has text");
+        let last = inked.iter().rposition(|&i| i).unwrap_or(first);
+        // "AaBbCcDd" begins at the left margin (1 point) and is whole: it is about 60 points wide.
+        assert!(first < 6, "the first line starts off the tile's left edge (ink from column {first})");
+        assert!(last - first > 40, "the first line is cut off by the tile's left edge (ink {first}..{last})");
+    }
+
     /// #663: gallery previews are dimmed in the dark theme, unless they show Switch Modes' dark
     /// page; the light theme keeps a white page.
     #[test]