Insert Design on the ASSEMBLE panel and in the File menu (#1240) (#1405)

component.insert_design (a saved part as a linked component) had no button, so an
assembly of separately saved parts looked impossible. It is now on the ASSEMBLE panel
of every tab and in the File menu; it asks for the file, and a STEP or mesh file picked
there is inserted as Insert STEP or Insert Mesh would.

Co-authored-by: Claude Opus 5.5 <[email protected]>

crates/engine/src/cmd/component_link.rs

@@ -16,7 +16,7 @@ use crate::params::{bad, str_, vec3};
 use crate::{EngineError, Result, Session};
 
 pub static COMMANDS: &[CommandSpec] = &[
-    CommandSpec::new("component.insert_design", "Insert Design", insert_design).icon("component").params(
+    CommandSpec::new("component.insert_design", "Insert Design", insert_design).at("SOLID", "ASSEMBLE").icon("component").params(
         "path: a .solidcraft design → a new component linked to it, holding its solid bodies as placed in that design; \
          name? (default: the design's name); parent?: component id or name (default: the active one); translate?: [x,y,z]",
     ),

crates/ui-egui/src/lib.rs

@@ -679,6 +679,21 @@ impl SolveApp {
             self.pick_open_command(id, json!({}));
             return;
         }
+        if id == "component.insert_design" {
+            // Another design becomes a linked component; a STEP or mesh file picked here is
+            // inserted the way Insert STEP or Insert Mesh would (#1240).
+            self.pick_open(|app, path| {
+                let Some(path) = path else { return };
+                if is_design_path(&path) {
+                    if app.run("component.insert_design", json!({ "path": path })).is_ok() {
+                        app.fit_view();
+                    }
+                } else {
+                    app.insert_path_async(&path);
+                }
+            });
+            return;
+        }
         if matches!(id, "file.insert_step" | "file.insert_mesh") {
             self.pick_open(|app, path| {
                 if let Some(path) = path {
@@ -1419,3 +1434,10 @@ pub fn now_ms() -> f64 {
 
 #[cfg(test)]
 mod picker_test_support;
+
+/// A SolidCraft design file (`.solidcraft`, or a design saved as JSON), as opposed to a STEP or
+/// mesh file.
+fn is_design_path(path: &str) -> bool {
+    let ext = std::path::Path::new(path).extension().and_then(|e| e.to_str()).unwrap_or("").to_ascii_lowercase();
+    matches!(ext.as_str(), "solidcraft" | "solvecraft" | "json")
+}

crates/ui-egui/src/toolbar.rs

@@ -390,6 +390,10 @@ fn file_menu(app: &mut SolveApp, ctx: &egui::Context) {
                     app.start("file.insert_mesh");
                     close = true;
                 }
+                if item_if(ui, &format!("{}…", app.tr_label("Insert Design")), "", shown) {
+                    app.start("component.insert_design");
+                    close = true;
+                }
                 if item_if(ui, app.tr("ui.save"), "Ctrl+S", shown) {
                     save(app);
                     close = true;

crates/ui-egui/src/workspace.rs

@@ -11,6 +11,7 @@ const ASSEMBLE: &[&str] = &[
     "component.create",
     "joint.create",
     "joint.as_built",
+    "component.insert_design",
     "joint.origin",
     "joint.rigid_group",
     "joint.drive",
@@ -212,4 +213,36 @@ mod tests {
         assert!(ids("PLASTIC", "MODIFY").contains(&"solid.shell"));
         assert!(panels("PLASTIC").is_some_and(|p| p.first() == Some(&"SETUP")));
     }
+
+    /// #1240: a saved part reaches an assembly from the ASSEMBLE panel (and the File menu) as a
+    /// linked component, and a STEP file picked there is inserted as Insert STEP would.
+    #[test]
+    fn insert_design_is_on_the_assemble_panel_and_inserts_a_saved_part() {
+        use serde_json::json;
+        for tab in ["SOLID", "SHEET METAL", "PLASTIC"] {
+            assert!(ids(tab, "ASSEMBLE").contains(&"component.insert_design"), "{tab}");
+        }
+        assert!(!ids("SOLID", "ASSEMBLE")[..3].contains(&"component.insert_design"), "Component, Joint and As-built Joint keep the big buttons");
+        let mut h = crate::scenario::Harness::new();
+        let part = h.dir.join("part1.solidcraft");
+        let mut s = solidcraft_engine::Session::default();
+        s.execute("solid.box", &json!({"length": 10, "width": 20, "height": 30})).unwrap();
+        s.execute("file.save", &json!({"path": part})).unwrap();
+        s.execute("file.export", &json!({"path": h.dir.join("part2.step")})).unwrap();
+        h.step(&json!({"choose_file": "part1.solidcraft"})).unwrap();
+        h.step(&json!({"start": "component.insert_design"})).unwrap();
+        h.frames(3);
+        let links = h.app.session.execute("component.links", &json!({})).unwrap();
+        assert_eq!(links["links"][0]["name"], "part1", "{links}");
+        assert_eq!(h.app.session.world_state().bodies.len(), 1);
+        h.step(&json!({"choose_file": "part2.step"})).unwrap();
+        h.step(&json!({"start": "component.insert_design"})).unwrap();
+        for _ in 0..600 {
+            if h.app.session.world_state().bodies.len() == 2 {
+                break;
+            }
+            h.frames(1);
+        }
+        assert_eq!(h.app.session.world_state().bodies.len(), 2, "the STEP file's body is inserted");
+    }
 }