Fix problem using copy constructor of Box

engine/src/conversion/codegen_rs/mod.rs

@@ -581,15 +581,22 @@ impl<'a> RsCodeGenerator<'a> {
                 })],
                 ..Default::default()
             },
-            Api::RustType { path, .. } => RsCodegenResult {
-                global_items: vec![parse_quote! {
-                    use super::#path;
-                }],
-                extern_rust_mod_items: vec![parse_quote! {
-                    type #id;
-                }],
-                ..Default::default()
-            },
+            Api::RustType { path, .. } => {
+                let id = path.get_final_ident();
+                RsCodegenResult {
+                    global_items: vec![parse_quote! {
+                        use super::#path;
+                    }],
+                    extern_rust_mod_items: vec![parse_quote! {
+                        type #id;
+                    }],
+                    bindgen_mod_items: vec![parse_quote! {
+                        #[allow(unused_imports)]
+                        use super::super::#id;
+                    }],
+                    ..Default::default()
+                }
+            }
             Api::RustFn {
                 details:
                     RustFun {

engine/src/known_types.rs

@@ -244,7 +244,9 @@ impl TypeDatabase {
             .map(|td| {
                 matches!(
                     td.behavior,
-                    Behavior::CxxContainerPtr | Behavior::CxxContainerVector
+                    Behavior::CxxContainerPtr
+                        | Behavior::CxxContainerVector
+                        | Behavior::RustContainerByValueSafe
                 )
             })
             .unwrap_or(false)

integration-tests/tests/integration_test.rs

@@ -7193,7 +7193,7 @@ fn test_cpp17() {
 }
 
 #[test]
-fn test_box() {
+fn test_box_extern_rust_type() {
     let hdr = indoc! {"
         #include <cxx.h>
         struct Foo;
@@ -7220,6 +7220,47 @@ fn test_box() {
     );
 }
 
+#[test]
+fn test_box_return_placement_new() {
+    let hdr = indoc! {"
+        #include <cxx.h>
+        struct Foo;
+        struct Foo2;
+        struct Ret {};
+        inline Ret take_box(rust::Box<Foo>, rust::Box<Foo2>) {
+            return Ret{};
+        }
+    "};
+    run_test_ex(
+        "",
+        hdr,
+        quote! {
+            let _ = ffi::take_box(
+                Box::new(Foo { a: "Hello".into() }),
+                Box::new(bar::Foo2 { a: "Goodbye".into() })
+            );
+        },
+        quote! {
+            generate!("take_box")
+            extern_rust_type!(Foo)
+            generate!("Ret")
+        },
+        None,
+        None,
+        Some(quote! {
+            pub struct Foo {
+                a: String,
+            }
+            mod bar {
+                #[autocxx::extern_rust::extern_rust_type]
+                pub struct Foo2 {
+                    pub a: String,
+                }
+            }
+        }),
+    );
+}
+
 #[test]
 fn test_box_via_extern_rust() {
     let hdr = indoc! {"