Fixed generating traits by codegen.

components/script/dom/bindings/codegen/CodegenRust.py

@@ -5629,7 +5629,7 @@ def contains_unsafe_arg(arguments):
 
         if methods:
             self.cgRoot = CGWrapper(CGIndenter(CGList(methods, "")),
-                                    pre="pub trait %sMethods {\n" % descriptor.interface.identifier.name,
+                                    pre="#[must_root] pub trait %sMethods {\n" % descriptor.interface.identifier.name,
                                     post="}")
         else:
             self.cgRoot = CGGeneric("")

components/script/dom/bindings/root.rs

@@ -126,7 +126,7 @@ where
 }
 
 /// A rooted reference to a DOM object.
-pub type DomRoot<T> = Root<Dom<T>>;
+pub type DomRoot<#[must_root] T> = Root<Dom<T>>;
 
 impl<T: Castable> DomRoot<T> {
     /// Cast a DOM object root upwards to one of the interfaces it derives from.

tests/unit/script_plugins/lib.rs

@@ -7,7 +7,6 @@ pub mod unrooted_must_root {
     ```
     #![feature(plugin)]
     #![plugin(script_plugins)]
-    #![feature(generic_param_attrs)]
 
     #[derive(Clone, Debug)]  // derive should not be checked
     #[must_root] struct Foo(i32);
@@ -71,7 +70,6 @@ pub mod unrooted_must_root {
     ```compile_fail
     #![feature(plugin)]
     #![plugin(script_plugins)]
-    #![feature(generic_param_attrs)]
 
     #[must_root] struct Foo(i32);
     struct Bar<#[must_root] T>(T);
@@ -89,7 +87,6 @@ pub mod unrooted_must_root {
     ```compile_fail
     #![feature(plugin)]
     #![plugin(script_plugins)]
-    #![feature(generic_param_attrs)]
 
     fn foo<T>() { }
     fn bar<#[must_root] U>() { foo::<U>(); }
@@ -103,7 +100,6 @@ pub mod unrooted_must_root {
     ```compile_fail
     #![feature(plugin)]
     #![plugin(script_plugins)]
-    #![feature(generic_param_attrs)]
 
     fn foo<#[must_root] T>() { }
     fn bar<#[must_root] U>() {
@@ -235,7 +231,6 @@ pub mod unrooted_must_root {
     ```compile_fail
     #![feature(plugin)]
     #![plugin(script_plugins)]
-    #![feature(generic_param_attrs)]
 
     #[must_root] struct Foo(i32);
     struct SomeContainer<T>(T);
@@ -259,7 +254,6 @@ pub mod unrooted_must_root {
     ```
     #![feature(plugin)]
     #![plugin(script_plugins)]
-    #![feature(generic_param_attrs)]
 
     #[must_root] struct Foo(i32);
     #[allow_unrooted_interior] struct SomeContainer<T>(T);
@@ -280,11 +274,35 @@ pub mod unrooted_must_root {
     */
     pub fn allowing_unrooted_interior() {}
 
+    /**
+    ```
+    #![feature(plugin)]
+    #![plugin(script_plugins)]
+
+    #[must_root] struct Foo(i32);
+
+    #[must_root] //-- this is needed!
+    trait Bar {
+        fn extract(&self) -> i32;
+    }
+
+    impl Bar for Foo {
+        fn extract(&self) -> i32 { self.0 }
+    }
+
+    fn test() {
+        Foo(3).extract();
+    }
+
+    fn main() {}
+    ```
+    */
+    pub fn allow_impl_for_must_root() {}
+
     /* *
     ```
     #![feature(plugin)]
     #![plugin(script_plugins)]
-    #![feature(generic_param_attrs)]
 
     #[derive(Default)]
     #[must_root] struct Foo(i32);