Layers: Merge Group for a selected group (#3832) (#3888)

* Layers: Merge Group for a selected group (#3832)

With a lone group selected, Layer > Merge Layers (Cmd+E) reads Merge Group and the
Layers panel's right-click menu offers Merge Group instead of Merge Down, as in
Photoshop. The new layer.mergeGroup command flattens the group's visible contents
into one pixel layer in its place, named after the group, keeping its opacity, blend
mode (Pass Through becomes Normal), clipping and locks. Before, Cmd+E on a group ran
Merge Down and merged the whole group into the layer below it.

* i18n: Vietnamese row for Merge Group

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

---------

Co-authored-by: Brandon Thomas <echelon@gmail.com>
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

crates/engine/src/commands.rs

@@ -782,6 +782,13 @@ fn build() -> Vec<CommandSpec> {
             })?;
             Ok(Value::Null)
         }),
+        cmd!("layer.mergeGroup", "Merge Group", ["Layer"], None, r##"{"layer":id?}"##, has_layer, |s, p| {
+            let id = layer_param(s, p)?;
+            if !s.active().and_then(|d| d.doc.layer(id)).is_some_and(|l| matches!(l.content, LayerContent::Group(_))) {
+                return Err(EngineError::Other("Merge Group needs a group".into()));
+            }
+            merge_group(s, id)
+        }),
         cmd!("layer.flattenImage", "Flatten Image", ["Layer"], None, "{}", has_doc, |s, _| {
             s.edit("Flatten Image", |doc, active| {
                 let fmt = doc.pixel_format();
@@ -1427,6 +1434,37 @@ pub(crate) fn layer_copy(doc: &Document, id: LayerId) -> Result<Layer> {
     Ok(dup)
 }
 
+/// Layer › Merge Group (⌘E with a group selected, #3832): the group's visible contents, as they
+/// show, become one pixel layer in its place, named after it. Like Photoshop, the layer keeps the
+/// group's opacity, blend mode (Pass Through becomes Normal), clipping and locks; the group's mask
+/// and style are applied to the pixels.
+fn merge_group(s: &mut Session, id: LayerId) -> Result<Value> {
+    s.edit("Merge Group", |doc, active| {
+        let group = doc.layer(id).ok_or(EngineError::NoLayer(id))?.clone();
+        if !group.visible {
+            return Err(EngineError::Other("the group is hidden".into()));
+        }
+        let fmt = doc.pixel_format();
+        let fmt = photocraft_color::PixelFormat::new(fmt.mode, fmt.sample, true);
+        let mut solo = group.clone();
+        solo.opacity = 1.0;
+        solo.blend = photocraft_doc::BlendMode::Normal;
+        solo.clipped = false;
+        let mut tmp = doc.clone();
+        tmp.layers = vec![solo];
+        let mut merged = Layer::new(group.name.clone(), LayerContent::Raster(pixels::composite_layers(&tmp, fmt, None)));
+        merged.id = group.id;
+        merged.opacity = group.opacity;
+        merged.blend = if group.blend == photocraft_doc::BlendMode::PassThrough { photocraft_doc::BlendMode::Normal } else { group.blend };
+        merged.clipped = group.clipped;
+        merged.locks = group.locks;
+        *doc.layer_mut(id).ok_or(EngineError::NoLayer(id))? = merged;
+        *active = Some(id);
+        Ok(())
+    })?;
+    Ok(json!({ "layer": id.0 }))
+}
+
 #[cfg(test)]
 mod registry_tests {
     use super::*;

crates/engine/src/layer_multi_cmds.rs

@@ -1217,6 +1217,12 @@ pub fn group_layers(s: &mut Session, p: &Value) -> Result<Value> {
 fn merge_layers(s: &mut Session) -> Result<Value> {
     let sel = selected(s);
     if sel.len() < 2 {
+        // ⌘E on a lone group is Photoshop's Merge Group (#3832); on a layer, Merge Down.
+        if let Some(&id) = sel.first()
+            && s.active().and_then(|d| d.doc.layer(id)).is_some_and(|l| matches!(l.content, LayerContent::Group(_)))
+        {
+            return s.execute("layer.mergeGroup", json!({ "layer": id.0 }));
+        }
         return s.execute("layer.mergeDown", json!({}));
     }
     let mid = s.edit("Merge Layers", |doc, active| {

crates/engine/src/tests.rs

@@ -1469,3 +1469,41 @@ fn delete_layer_preserves_an_unaffected_active_layer_and_last_layer_guard() {
     assert_eq!(s.active().unwrap().active_layer, Some(other));
     assert_eq!(s.active().unwrap().history.past_len(), before);
 }
+
+#[test]
+fn merge_down_on_a_group_merges_the_group() {
+    // #3832: with a group selected, Merge Down is Photoshop's Merge Group (⌘E): the group's
+    // contents become one layer in its place, named after it, and the layer below is untouched.
+    let mut s = session_with_doc();
+    let below = s.execute("layer.new.layer", json!({"name": "Below"})).unwrap()["layer"].as_u64().unwrap();
+    s.execute("edit.fill", json!({"color": "#00ff00"})).unwrap();
+    let a = s.execute("layer.new.layer", json!({"name": "A"})).unwrap()["layer"].as_u64().unwrap();
+    s.execute("select.rect", json!({"x": 0, "y": 0, "width": 10, "height": 48})).unwrap();
+    s.execute("edit.fill", json!({"color": "#ff0000"})).unwrap();
+    s.execute("select.deselect", json!({})).unwrap();
+    let b = s.execute("layer.new.layer", json!({"name": "B"})).unwrap()["layer"].as_u64().unwrap();
+    s.execute("select.rect", json!({"x": 20, "y": 0, "width": 10, "height": 48})).unwrap();
+    s.execute("edit.fill", json!({"color": "#0000ff"})).unwrap();
+    s.execute("select.deselect", json!({})).unwrap();
+    s.execute("layer.select", json!({"layer": b})).unwrap();
+    s.execute("layer.select", json!({"layer": a, "mode": "add"})).unwrap();
+    let group = s.execute("layer.groupLayers", json!({"name": "Badge"})).unwrap()["layer"].as_u64().unwrap();
+    s.execute("layer.setProps", json!({"layer": group, "opacity": 0.5})).ok();
+    let before = [px(&mut s, 5, 5), px(&mut s, 25, 5), px(&mut s, 50, 5)];
+    let layers = s.active().unwrap().doc.layer_count();
+    s.execute("layer.select", json!({"layer": group})).unwrap();
+    s.execute("layer.mergeLayers", json!({})).unwrap();
+    let st = s.active().unwrap();
+    let merged = st.doc.layer(st.active_layer.unwrap()).unwrap().clone();
+    assert_eq!(merged.name, "Badge");
+    assert!(matches!(merged.content, photocraft_doc::LayerContent::Raster(_)), "one pixel layer");
+    assert!(st.doc.layer(photocraft_doc::LayerId(below)).is_some(), "the layer below stays");
+    assert_eq!(st.doc.layer_count(), layers - 2, "group and its two layers became one");
+    let after = [px(&mut s, 5, 5), px(&mut s, 25, 5), px(&mut s, 50, 5)];
+    for (a, b) in before.iter().zip(&after) {
+        assert!(a.iter().zip(b).all(|(x, y)| (x - y).abs() < 1.0 / 255.0), "{before:?} -> {after:?}");
+    }
+    // Undo brings the group back.
+    s.execute("edit.undo", json!({})).unwrap();
+    assert!(s.active().unwrap().doc.layer(photocraft_doc::LayerId(group)).is_some());
+}

crates/ui-egui/src/i18n/cs.tsv

@@ -398,6 +398,7 @@
 	Select Linked Layers	Vybrat propojené vrstvy
 	Merge Layers	Sloučit vrstvy
 	Merge Down	Sloučit dolů
+	Merge Group	Sloučit skupinu
 	Merge Visible	Sloučit viditelné
 	Stamp Visible	Otisknout viditelné
 	Select Layer Above	Vybrat vrstvu nad

crates/ui-egui/src/i18n/de.tsv

@@ -394,6 +394,7 @@
 	Select Linked Layers	Verknüpfte Ebenen auswählen
 	Merge Layers	Ebenen zusammenfügen
 	Merge Down	Nach unten zusammenfügen
+	Merge Group	Gruppe zusammenfügen
 	Merge Visible	Sichtbare zusammenfügen
 	Stamp Visible	Sichtbare Ebenen stempeln
 	Select Layer Above	Ebene darüber auswählen

crates/ui-egui/src/i18n/el.tsv

@@ -1838,6 +1838,7 @@
 	New Guide Layout…	Νέα διάταξη οδηγών…
 	New Guides From Shape	Νέοι οδηγοί από σχήμα
 	Merge Down	Συγχώνευση με το υποκείμενο επίπεδο
+	Merge Group	Συγχώνευση ομάδας
 	Stamp Visible	Συνένωση ορατών σε νέο επίπεδο
 	Select Layer Above	Επιλογή επάνω επιπέδου
 	Select Layer Below	Επιλογή κάτω επιπέδου

crates/ui-egui/src/i18n/es.tsv

@@ -391,6 +391,7 @@
 	Select Linked Layers	Seleccionar capas vinculadas
 	Merge Layers	Combinar capas
 	Merge Down	Combinar hacia abajo
+	Merge Group	Combinar grupo
 	Merge Visible	Combinar visibles
 	Stamp Visible	Sellar visibles
 	Select Layer Above	Seleccionar la capa de arriba

crates/ui-egui/src/i18n/fr.tsv

@@ -387,6 +387,7 @@
 	Select Linked Layers	Sélectionner les calques liés
 	Merge Layers	Fusionner les calques
 	Merge Down	Fusionner avec le calque inférieur
+	Merge Group	Fusionner le groupe
 	Merge Visible	Fusionner les calques visibles
 	Stamp Visible	Tamponner les calques visibles
 	Stamp Down	Tamponner sur le calque inférieur

crates/ui-egui/src/i18n/id.tsv

@@ -380,6 +380,7 @@
 	Select Linked Layers	Pilih Layer Tertaut
 	Merge Layers	Gabungkan Layer
 	Merge Down	Gabung ke Bawah
+	Merge Group	Gabungkan Grup
 	Merge Visible	Gabung yang Terlihat
 	Stamp Visible	Stamp yang Terlihat
 	Stamp Down	Stamp ke Bawah

crates/ui-egui/src/i18n/it.tsv

@@ -390,6 +390,7 @@
 	Select Linked Layers	Seleziona livelli collegati
 	Merge Layers	Unisci livelli
 	Merge Down	Unisci sotto
+	Merge Group	Unisci gruppo
 	Merge Visible	Unisci visibili
 	Stamp Visible	Unisci visibili in nuovo
 	Select Layer Above	Seleziona livello sopra

crates/ui-egui/src/i18n/ja.tsv

@@ -391,6 +391,7 @@
 	Select Linked Layers	リンクしたレイヤーを選択
 	Merge Layers	レイヤーを結合
 	Merge Down	下のレイヤーと結合
+	Merge Group	グループを結合
 	Merge Visible	表示レイヤーを結合
 	Stamp Visible	表示レイヤーをスタンプ
 	Select Layer Above	上のレイヤーを選択

crates/ui-egui/src/i18n/ko.tsv

@@ -375,6 +375,7 @@
 	Select Linked Layers	연결된 레이어 선택
 	Merge Layers	레이어 병합
 	Merge Down	아래 레이어와 병합
+	Merge Group	그룹 병합
 	Merge Visible	보이는 레이어 병합
 	Stamp Visible	보이는 레이어의 병합 사본 만들기
 	Select Layer Above	위 레이어 선택

crates/ui-egui/src/i18n/nl.tsv

@@ -383,6 +383,7 @@
 	Select Linked Layers	Gekoppelde lagen selecteren
 	Merge Layers	Lagen samenvoegen
 	Merge Down	Omlaag samenvoegen
+	Merge Group	Groep samenvoegen
 	Merge Visible	Zichtbare samenvoegen
 	Stamp Visible	Zichtbare stempelen
 	Select Layer Above	Laag erboven selecteren

crates/ui-egui/src/i18n/pl.tsv

@@ -389,6 +389,7 @@
 	Select Linked Layers	Zaznacz połączone warstwy
 	Merge Layers	Scal warstwy
 	Merge Down	Scal w dół
+	Merge Group	Scal grupę
 	Merge Visible	Scal widoczne
 	Stamp Visible	Odbij widoczne
 	Select Layer Above	Zaznacz warstwę powyżej

crates/ui-egui/src/i18n/pt-br.tsv

@@ -383,6 +383,7 @@
 	Select Linked Layers	Selecionar camadas vinculadas
 	Merge Layers	Mesclar camadas
 	Merge Down	Mesclar para baixo
+	Merge Group	Mesclar grupo
 	Merge Visible	Mesclar visíveis
 	Stamp Visible	Carimbar visíveis
 	Stamp Down	Carimbar para baixo

crates/ui-egui/src/i18n/ru.tsv

@@ -1897,6 +1897,7 @@
 	Lock Layers…	Заблокировать слои…
 	Mean	Среднее
 	Merge Down	Выполнить сведение
+	Merge Group	Объединить группу
 	Merge Layers	Объединить слои
 	Merge Shape Components	Объединить компоненты фигуры
 	Merge Visible	Свести видимые

crates/ui-egui/src/i18n/uk.tsv

@@ -1876,6 +1876,7 @@
 	Lock Layers…	Заблокувати шари…
 	Mean	Середнє значення
 	Merge Down	Об'єднати з нижнім
+	Merge Group	Об'єднати групу
 	Merge Layers	Об'єднати шари
 	Merge Shape Components	Об'єднати компоненти фігури
 	Merge Visible	Об'єднати видимі

crates/ui-egui/src/i18n/vi.tsv

@@ -936,6 +936,7 @@
 	Disable Layer Mask	Tắt mặt nạ lớp
 	Release Clipping Mask	Nhả mặt nạ cắt
 	Merge Down	Gộp xuống
+	Merge Group	Gộp nhóm
 	Quick Export As PNG	Xuất nhanh dạng PNG
 	Rename Layer…	Đổi tên lớp…
 	Frame from Layers…	Frame từ các lớp…

crates/ui-egui/src/i18n/zh-hans.tsv

@@ -393,6 +393,7 @@
 	Select Linked Layers	选择链接的图层
 	Merge Layers	合并图层
 	Merge Down	向下合并
+	Merge Group	合并组
 	Merge Visible	合并可见图层
 	Stamp Visible	盖印可见图层
 	Select Layer Above	选择上方图层

crates/ui-egui/src/i18n/zh-hant.tsv

@@ -398,6 +398,7 @@
 	Select Linked Layers	選取連結的圖層
 	Merge Layers	合併圖層
 	Merge Down	向下合併圖層
+	Merge Group	合併群組
 	Merge Visible	合併可見圖層
 	Stamp Visible	蓋印可見圖層
 	Select Layer Above	選取上方圖層

crates/ui-egui/src/layer_menu_ui.rs

@@ -111,6 +111,9 @@ pub fn entries(l: &Layer, multi: bool, has_selection: bool) -> Vec<Entry> {
     v.push(None);
     if multi {
         v.push(Some((tl!("Merge Layers"), "layer.mergeLayers")));
+    } else if matches!(l.content, LayerContent::Group(_)) {
+        // Photoshop's Merge Group: a group merges itself, not into the layer below (#3832).
+        v.push(Some((tl!("Merge Group"), "layer.mergeGroup")));
     } else {
         v.push(Some((tl!("Merge Down"), "layer.mergeDown")));
     }
@@ -654,6 +657,31 @@ mod tests {
         assert!(ids.contains(&"layer.mergeLayers"));
     }
 
+    /// #3832: a group's right-click menu and the Layer menu offer Photoshop's Merge Group, which
+    /// merges the group itself (not into the layer below), and it is enabled.
+    #[test]
+    fn a_group_offers_merge_group() {
+        let mut s = photocraft_engine::Session::new();
+        s.execute("file.new", json!({"width": 10, "height": 10})).unwrap();
+        s.execute("layer.new.layer", json!({})).unwrap();
+        s.execute("layer.groupLayers", json!({"name": "G"})).unwrap();
+        let st = s.active().unwrap();
+        let g = st.doc.layer(st.active_layer.unwrap()).unwrap().clone();
+        let e: Vec<(&str, &str)> = entries(&g, false, false).into_iter().flatten().collect();
+        assert!(e.contains(&("Merge Group", "layer.mergeGroup")), "{e:?}");
+        assert!(!e.iter().any(|x| x.0 == "Merge Down"));
+        let mut app = crate::PhotocraftApp::new(s, Default::default());
+        app.sync_views();
+        let items = crate::menus::menu_items(&app);
+        let item = items.iter().find(|i| i.id == "layer.mergeLayers").unwrap();
+        assert_eq!(item.label, "Merge Group");
+        assert!(item.enabled, "Merge Group runs on a group");
+        // A plain layer keeps Merge Layers.
+        app.run("layer.new.layer", json!({})).unwrap();
+        let items = crate::menus::menu_items(&app);
+        assert_eq!(items.iter().find(|i| i.id == "layer.mergeLayers").unwrap().label, "Merge Layers");
+    }
+
     #[test]
     fn add_mask_uses_the_selection() {
         assert_eq!(add_mask_command(false, false), "layer.layerMask.revealAll");

crates/ui-egui/src/menus.rs

@@ -966,6 +966,14 @@ pub fn menu_items(app: &PhotocraftApp) -> Vec<MenuItem> {
     {
         item.label = crate::layer_menu_ui::mask_toggle_label(mask.enabled).into();
     }
+    // Layer › Merge Layers reads Merge Group with just a group selected, as in Photoshop (#3832).
+    if let Some(st) = app.session.active()
+        && st.selected_layers().len() <= 1
+        && st.active_layer.and_then(|id| st.doc.layer(id)).is_some_and(|l| matches!(l.content, photocraft_doc::LayerContent::Group(_)))
+        && let Some(item) = items.iter_mut().find(|i| i.id == "layer.mergeLayers")
+    {
+        item.label = "Merge Group".into();
+    }
     // The File quick-export command uses the format selected in Export Preferences.
     // On the web it intentionally downloads PNG until the quick-export service supports
     // the other formats; the Layer quick-export command also always produces PNG.