Give name to the builtin element's callback argument

internal/compiler/builtins.slint

@@ -126,16 +126,16 @@ export component TouchArea {
     callback clicked;
     callback double-clicked;
     callback moved;
-    callback pointer-event(PointerEvent);
-    callback scroll-event(PointerScrollEvent) -> EventResult;
+    callback pointer-event(event: PointerEvent);
+    callback scroll-event(event: PointerScrollEvent) -> EventResult;
     //-default_size_binding:expands_to_parent_geometry
 }
 
 export component FocusScope {
     in property <bool> enabled: true;
     out property <bool> has-focus;
-    callback key_pressed(KeyEvent) -> EventResult;
-    callback key_released(KeyEvent) -> EventResult;
+    callback key_pressed(event: KeyEvent) -> EventResult;
+    callback key_released(event: KeyEvent) -> EventResult;
     callback focus_changed_event();
     //-default_size_binding:expands_to_parent_geometry
     //-accepts_focus
@@ -189,8 +189,8 @@ component MenuBar {
     //-disallow_global_types_as_child_elements
     in property <[MenuEntry]> entries;
 
-    callback activated(MenuEntry);
-    callback sub-menu(MenuEntry) -> [MenuEntry];
+    callback activated(entry: MenuEntry);
+    callback sub-menu(entry: MenuEntry) -> [MenuEntry];
 
     // Currently experimental
     //-is_internal
@@ -200,8 +200,8 @@ component MenuBar {
 export component ContextMenu {
     function show() {}
     //in property <[MenuEntry]> entries;
-    callback activated(MenuEntry);
-    callback sub-menu(MenuEntry) -> [MenuEntry];
+    callback activated(entry: MenuEntry);
+    callback sub-menu(entry: MenuEntry) -> [MenuEntry];
     //-default_size_binding:expands_to_parent_geometry
 
     // Currently experimental
@@ -262,7 +262,7 @@ export component TextInput {
     callback accepted;
     callback rejected;
     callback edited;
-    callback cursor_position_changed(Point);
+    callback cursor_position_changed(position: Point);
     in property <bool> enabled: true;
     in property <bool> single-line: true;
     in property <bool> read-only: false;

tools/lsp/language/completion.rs

@@ -1552,5 +1552,23 @@ mod tests {
             res.iter().find(|ci| ci.label == "accessible-action-set-value").unwrap().insert_text,
             Some("accessible-action-set-value => {$1}".into())
         );
+        let source = r#"
+            import { StandardTableView } from "std-widgets.slint";
+            component MyTouchArea inherits TouchArea {}
+            component Foo {
+                MyTouchArea {
+                    🔺
+                }
+            }
+        "#;
+        let res = get_completions(source).unwrap();
+        assert_eq!(
+            res.iter().find(|ci| ci.label == "pointer-event").unwrap().insert_text,
+            Some("pointer-event(event) => {$1}".into())
+        );
+        assert_eq!(
+            res.iter().find(|ci| ci.label == "clicked").unwrap().insert_text,
+            Some("clicked => {$1}".into())
+        );
     }
 }

tools/lsp/language/hover.rs

@@ -142,6 +142,7 @@ export component Test {
          root.fn_loc();
       }
       property <Eee> e: Eee.E2;
+      pointer-event(aaa) => {}
   }
   Rectangle {
     background: red;
@@ -215,6 +216,11 @@ export component Test {
             // Fixme: this uses LogicalPoint instead of Point because of implementation details
             "```slint\ncallback row-pointer-event(row-index: int, event: PointerEvent, mouse-position: LogicalPosition)\n```",
         );
+        assert_tooltip(
+            get_tooltip(&mut dc, find_tk("pointer-event", 5.into())),
+            "```slint\ncallback pointer-event(event: PointerEvent)\n```",
+        );
+        // functions
         assert_tooltip(
             get_tooltip(&mut dc, find_tk("fn_glob(local-prop)", 1.into())),
             "```slint\npure function fn-glob(abc: int)\n```",