crown: Check closure bodies for unrooted types and fix root TransmitBodyPromise* (#39534)

We should also check closure bodies for unrooted expressions. 

Testing: New crown tests
Fixes: #37331
Fixes (partial): #37330

---------

Signed-off-by: sagudev <16504129+sagudev@users.noreply.github.com>

components/script/body.rs

@@ -234,6 +234,7 @@ impl TransmitBodyConnectHandler {
             task!(setup_native_body_promise_handler: move || {
                 let rooted_stream = stream.root();
                 let global = rooted_stream.global();
+                let cx = GlobalScope::get_cx();
 
                 // Step 4, the result of reading a chunk from body’s stream with reader.
                 let promise = rooted_stream.read_a_chunk(CanGc::note());
@@ -241,20 +242,20 @@ impl TransmitBodyConnectHandler {
                 // Step 5, the parallel steps waiting for and handling the result of the read promise,
                 // are a combination of the promise native handler here,
                 // and the corresponding IPC route in `component::net::http_loader`.
-                let promise_handler = Box::new(TransmitBodyPromiseHandler {
+                rooted!(in(*cx) let mut promise_handler = Some(TransmitBodyPromiseHandler {
                     bytes_sender: bytes_sender.clone(),
                     stream: Dom::from_ref(&rooted_stream.clone()),
                     control_sender: control_sender.clone(),
-                });
+                }));
 
-                let rejection_handler = Box::new(TransmitBodyPromiseRejectionHandler {
+                rooted!(in(*cx) let mut rejection_handler = Some(TransmitBodyPromiseRejectionHandler {
                     bytes_sender,
                     stream: Dom::from_ref(&rooted_stream.clone()),
                     control_sender,
-                });
+                }));
 
                 let handler =
-                    PromiseNativeHandler::new(&global, Some(promise_handler), Some(rejection_handler), CanGc::note());
+                    PromiseNativeHandler::new(&global, promise_handler.take().map(|h| Box::new(h) as Box<_>), rejection_handler.take().map(|h| Box::new(h) as Box<_>), CanGc::note());
 
                 let realm = enter_realm(&*global);
                 let comp = InRealm::Entered(&realm);
@@ -278,6 +279,8 @@ struct TransmitBodyPromiseHandler {
     control_sender: IpcSender<BodyChunkRequest>,
 }
 
+impl js::gc::Rootable for TransmitBodyPromiseHandler {}
+
 impl Callback for TransmitBodyPromiseHandler {
     /// Step 5 of <https://fetch.spec.whatwg.org/#concept-request-transmit-body>
     fn callback(&self, cx: JSContext, v: HandleValue, _realm: InRealm, can_gc: CanGc) {
@@ -332,6 +335,8 @@ struct TransmitBodyPromiseRejectionHandler {
     control_sender: IpcSender<BodyChunkRequest>,
 }
 
+impl js::gc::Rootable for TransmitBodyPromiseRejectionHandler {}
+
 impl Callback for TransmitBodyPromiseRejectionHandler {
     /// <https://fetch.spec.whatwg.org/#concept-request-transmit-body>
     fn callback(&self, _cx: JSContext, _v: HandleValue, _realm: InRealm, can_gc: CanGc) {

support/crown/src/unrooted_must_root.rs

@@ -399,10 +399,10 @@ impl<'tcx> LateLintPass<'tcx> for UnrootedPass {
                     n.as_str() == "default" ||
                     n.as_str() == "Wrap"
             },
-            visit::FnKind::Closure => return,
+            visit::FnKind::Closure => false,
         };
 
-        if !in_derive_expn(span) {
+        if !in_derive_expn(span) && !matches!(kind, visit::FnKind::Closure) {
             let sig = cx.tcx.type_of(def_id).skip_binder().fn_sig(cx.tcx);
 
             for (arg, ty) in decl.inputs.iter().zip(sig.inputs().skip_binder().iter()) {

support/crown/tests/compile-fail/unrooted_must_root_body.rs

@@ -0,0 +1,14 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+//@rustc-env:RUSTC_BOOTSTRAP=1
+
+#[crown::unrooted_must_root_lint::must_root]
+struct Foo(i32);
+
+fn foo2() {
+    let foo = Foo(0);
+    //~^ ERROR: Expression of type Foo must be rooted
+}
+
+fn main() {}

support/crown/tests/compile-fail/unrooted_must_root_closure_body.rs

@@ -0,0 +1,16 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+//@rustc-env:RUSTC_BOOTSTRAP=1
+
+#[crown::unrooted_must_root_lint::must_root]
+struct Foo(i32);
+
+fn foo2() {
+    || {
+        let foo = Foo(0);
+        //~^ ERROR: Expression of type Foo must be rooted
+    };
+}
+
+fn main() {}