Support objects in WebIDL unions

Fixes #17011

1 files changed, 13 insertions, 12 deletions

diff --git a/components/script/dom/bindings/codegen/CodegenRust.py b/components/script/dom/bindings/codegen/CodegenRust.py
index d2d090f8350..55e72086f12 100644
--- a/components/script/dom/bindings/codegen/CodegenRust.py
+++ b/components/script/dom/bindings/codegen/CodegenRust.py
@@ -1075,20 +1075,24 @@ def getJSToNativeConversionInfo(type, descriptorProvider, failureCode=None,
     if type.isObject():
         assert not isEnforceRange and not isClamp
 
-        # TODO: Need to root somehow
-        # https://github.com/servo/servo/issues/6382
+        templateBody = "${val}.get().to_object()"
         default = "ptr::null_mut()"
-        templateBody = wrapObjectTemplate("${val}.get().to_object()",
-                                          default,
-                                          isDefinitelyObject, type, failureCode)
 
-        if isMember in ("Dictionary", "Union"):
+        # TODO: Do we need to do the same for dictionaries?
+        if isMember == "Union":
+            templateBody = "RootedTraceableBox::from_box(Heap::boxed(%s))" % templateBody
+            default = "RootedTraceableBox::new(Heap::default())"
+            declType = CGGeneric("RootedTraceableBox<Heap<*mut JSObject>>")
+        elif isMember == "Dictionary":
             declType = CGGeneric("Heap<*mut JSObject>")
         else:
             # TODO: Need to root somehow
             # https://github.com/servo/servo/issues/6382
             declType = CGGeneric("*mut JSObject")
 
+        templateBody = wrapObjectTemplate(templateBody, default,
+                                          isDefinitelyObject, type, failureCode)
+
         return handleOptional(templateBody, declType,
                               handleDefaultNull(default))
 
@@ -4291,11 +4295,13 @@ class CGUnionConversionStruct(CGThing):
         else:
             mozMapObject = None
 
-        hasObjectTypes = interfaceObject or arrayObject or dateObject or object or mozMapObject
+        hasObjectTypes = object or interfaceObject or arrayObject or dateObject or mozMapObject
         if hasObjectTypes:
             # "object" is not distinguishable from other types
             assert not object or not (interfaceObject or arrayObject or dateObject or callbackObject or mozMapObject)
             templateBody = CGList([], "\n")
+            if object:
+                templateBody.append(object)
             if interfaceObject:
                 templateBody.append(interfaceObject)
             if arrayObject:
@@ -4363,11 +4369,6 @@ class CGUnionConversionStruct(CGThing):
         returnType = "Result<Option<%s>, ()>" % actualType
         jsConversion = templateVars["jsConversion"]
 
-        # Any code to convert to Object is unused, since we're already converting
-        # from an Object value.
-        if t.name == 'Object':
-            return CGGeneric('')
-
         return CGWrapper(
             CGIndenter(jsConversion, 4),
             pre="unsafe fn TryConvertTo%s(cx: *mut JSContext, value: HandleValue) -> %s {\n"