Compile WebIDL return type "object" to NonZero<*mut JSObject>

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

@@ -1349,7 +1349,10 @@ def getRetvalDeclarationForType(returnType, descriptorProvider):
     if returnType.isAny():
         return CGGeneric("JSVal")
     if returnType.isObject() or returnType.isSpiderMonkeyInterface():
-        return CGGeneric("*mut JSObject")
+        result = CGGeneric("NonZero<*mut JSObject>")
+        if returnType.nullable():
+            result = CGWrapper(result, pre="Option<", post=">")
+        return result
     if returnType.isSequence():
         result = getRetvalDeclarationForType(innerSequenceType(returnType), descriptorProvider)
         result = CGWrapper(result, pre="Vec<", post=">")
@@ -5323,6 +5326,7 @@ def generate_imports(config, cgthings, descriptors, callbacks=None, dictionaries
         enums = []
 
     return CGImports(cgthings, descriptors, callbacks, dictionaries, enums, [
+        'core::nonzero::NonZero',
         'js',
         'js::JSCLASS_GLOBAL_SLOT_COUNT',
         'js::JSCLASS_IS_DOMJSCLASS',

components/script/dom/bindings/iterable.rs

@@ -6,6 +6,7 @@
 
 //! Implementation of `iterable<...>` and `iterable<..., ...>` WebIDL declarations.
 
+use core::nonzero::NonZero;
 use dom::bindings::codegen::Bindings::IterableIteratorBinding::IterableKeyAndValueResult;
 use dom::bindings::codegen::Bindings::IterableIteratorBinding::IterableKeyOrValueResult;
 use dom::bindings::error::Fallible;
@@ -95,38 +96,41 @@ impl<T: Reflectable + JSTraceable + Iterable> IterableIterator<T> {
 
     /// Return the next value from the iterable object.
     #[allow(non_snake_case)]
-    pub fn Next(&self, cx: *mut JSContext) -> Fallible<*mut JSObject> {
+    pub fn Next(&self, cx: *mut JSContext) -> Fallible<NonZero<*mut JSObject>> {
         let index = self.index.get();
         rooted!(in(cx) let mut value = UndefinedValue());
         rooted!(in(cx) let mut rval = ptr::null_mut());
-        if index >= self.iterable.get_iterable_length() {
-            return dict_return(cx, rval.handle_mut(), true, value.handle())
-                .map(|_| rval.handle().get());
-        }
-        let result = match self.type_ {
-            IteratorType::Keys => {
-                unsafe {
-                    self.iterable.get_key_at_index(index).to_jsval(cx, value.handle_mut());
+        let result = if index >= self.iterable.get_iterable_length() {
+            dict_return(cx, rval.handle_mut(), true, value.handle())
+        } else {
+            match self.type_ {
+                IteratorType::Keys => {
+                    unsafe {
+                        self.iterable.get_key_at_index(index).to_jsval(cx, value.handle_mut());
+                    }
+                    dict_return(cx, rval.handle_mut(), false, value.handle())
                 }
-                dict_return(cx, rval.handle_mut(), false, value.handle())
-            }
-            IteratorType::Values => {
-                unsafe {
-                    self.iterable.get_value_at_index(index).to_jsval(cx, value.handle_mut());
+                IteratorType::Values => {
+                    unsafe {
+                        self.iterable.get_value_at_index(index).to_jsval(cx, value.handle_mut());
+                    }
+                    dict_return(cx, rval.handle_mut(), false, value.handle())
                 }
-                dict_return(cx, rval.handle_mut(), false, value.handle())
-            }
-            IteratorType::Entries => {
-                rooted!(in(cx) let mut key = UndefinedValue());
-                unsafe {
-                    self.iterable.get_key_at_index(index).to_jsval(cx, key.handle_mut());
-                    self.iterable.get_value_at_index(index).to_jsval(cx, value.handle_mut());
+                IteratorType::Entries => {
+                    rooted!(in(cx) let mut key = UndefinedValue());
+                    unsafe {
+                        self.iterable.get_key_at_index(index).to_jsval(cx, key.handle_mut());
+                        self.iterable.get_value_at_index(index).to_jsval(cx, value.handle_mut());
+                    }
+                    key_and_value_return(cx, rval.handle_mut(), key.handle(), value.handle())
                 }
-                key_and_value_return(cx, rval.handle_mut(), key.handle(), value.handle())
             }
         };
         self.index.set(index + 1);
-        result.map(|_| rval.handle().get())
+        result.map(|_| {
+            assert!(!rval.is_null());
+            unsafe { NonZero::new(rval.get()) }
+        })
     }
 }
 

components/script/dom/crypto.rs

@@ -2,6 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+use core::nonzero::NonZero;
 use dom::bindings::cell::DOMRefCell;
 use dom::bindings::codegen::Bindings::CryptoBinding;
 use dom::bindings::codegen::Bindings::CryptoBinding::CryptoMethods;
@@ -43,7 +44,8 @@ impl CryptoMethods for Crypto {
     fn GetRandomValues(&self,
                        _cx: *mut JSContext,
                        input: *mut JSObject)
-                       -> Fallible<*mut JSObject> {
+                       -> Fallible<NonZero<*mut JSObject>> {
+        assert!(!input.is_null());
         let mut data = match unsafe { array_buffer_view_data::<u8>(input) } {
             Some(data) => data,
             None => {
@@ -62,7 +64,7 @@ impl CryptoMethods for Crypto {
 
         self.rng.borrow_mut().fill_bytes(&mut data);
 
-        Ok(input)
+        Ok(unsafe { NonZero::new(input) })
     }
 }
 

components/script/dom/document.rs

@@ -2,6 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+use core::nonzero::NonZero;
 use document_loader::{DocumentLoader, LoadType};
 use dom::activation::{ActivationSource, synthetic_click_activation};
 use dom::attr::Attr;
@@ -90,7 +91,7 @@ use euclid::point::Point2D;
 use html5ever::tree_builder::{LimitedQuirks, NoQuirks, Quirks, QuirksMode};
 use ipc_channel::ipc::{self, IpcSender};
 use js::jsapi::JS_GetRuntime;
-use js::jsapi::{JSContext, JSObject, JSRuntime};
+use js::jsapi::{JSContext, JSObject, JSRuntime, JS_NewPlainObject};
 use msg::constellation_msg::{ALT, CONTROL, SHIFT, SUPER};
 use msg::constellation_msg::{Key, KeyModifiers, KeyState};
 use msg::constellation_msg::{PipelineId, ReferrerPolicy, SubpageId};
@@ -116,7 +117,6 @@ use std::collections::hash_map::Entry::{Occupied, Vacant};
 use std::default::Default;
 use std::iter::once;
 use std::mem;
-use std::ptr;
 use std::rc::Rc;
 use std::sync::Arc;
 use string_cache::{Atom, QualName};
@@ -2689,8 +2689,10 @@ impl DocumentMethods for Document {
         self.set_body_attribute(&atom!("text"), value)
     }
 
+    #[allow(unsafe_code)]
     // https://html.spec.whatwg.org/multipage/#dom-tree-accessors:dom-document-nameditem-filter
-    fn NamedGetter(&self, _cx: *mut JSContext, name: DOMString, found: &mut bool) -> *mut JSObject {
+    fn NamedGetter(&self, cx: *mut JSContext, name: DOMString, found: &mut bool)
+                   -> NonZero<*mut JSObject> {
         #[derive(JSTraceable, HeapSizeOf)]
         struct NamedElementFilter {
             name: Atom,
@@ -2759,11 +2761,15 @@ impl DocumentMethods for Document {
                     *found = true;
                     // TODO: Step 2.
                     // Step 3.
-                    return first.reflector().get_jsobject().get();
+                    return unsafe {
+                        NonZero::new(first.reflector().get_jsobject().get())
+                    };
                 }
             } else {
                 *found = false;
-                return ptr::null_mut();
+                return unsafe {
+                    NonZero::new(JS_NewPlainObject(cx))
+                };
             }
         }
         // Step 4.
@@ -2772,7 +2778,9 @@ impl DocumentMethods for Document {
             name: name,
         };
         let collection = HTMLCollection::create(self.window(), root, box filter);
-        collection.reflector().get_jsobject().get()
+        unsafe {
+            NonZero::new(collection.reflector().get_jsobject().get())
+        }
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-tree-accessors:supported-property-names

components/script/dom/imagedata.rs

@@ -2,6 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+use core::nonzero::NonZero;
 use dom::bindings::codegen::Bindings::ImageDataBinding;
 use dom::bindings::codegen::Bindings::ImageDataBinding::ImageDataMethods;
 use dom::bindings::global::GlobalRef;
@@ -82,9 +83,10 @@ impl ImageDataMethods for ImageData {
         self.height
     }
 
+    #[allow(unsafe_code)]
     // https://html.spec.whatwg.org/multipage/#dom-imagedata-data
-    fn Data(&self, _: *mut JSContext) -> *mut JSObject {
+    fn Data(&self, _: *mut JSContext) -> NonZero<*mut JSObject> {
         assert!(!self.data.get().is_null());
-        self.data.get()
+        unsafe { NonZero::new(self.data.get()) }
     }
 }

components/script/dom/testbinding.rs

@@ -4,6 +4,7 @@
 
 // check-tidy: no specs after this line
 
+use core::nonzero::NonZero;
 use dom::bindings::codegen::Bindings::EventListenerBinding::EventListener;
 use dom::bindings::codegen::Bindings::FunctionBinding::Function;
 use dom::bindings::codegen::Bindings::TestBindingBinding;
@@ -139,21 +140,21 @@ impl TestBindingMethods for TestBinding {
     }
     fn SetUnion9Attribute(&self, _: ByteStringOrLong) {}
     #[allow(unsafe_code)]
-    fn ArrayAttribute(&self, cx: *mut JSContext) -> *mut JSObject {
+    fn ArrayAttribute(&self, cx: *mut JSContext) -> NonZero<*mut JSObject> {
         unsafe {
             rooted!(in(cx) let array = JS_NewUint8ClampedArray(cx, 16));
             assert!(!array.is_null());
-            array.get()
+            NonZero::new(array.get())
         }
     }
     fn AnyAttribute(&self, _: *mut JSContext) -> JSVal { NullValue() }
     fn SetAnyAttribute(&self, _: *mut JSContext, _: HandleValue) {}
     #[allow(unsafe_code)]
-    fn ObjectAttribute(&self, cx: *mut JSContext) -> *mut JSObject {
+    fn ObjectAttribute(&self, cx: *mut JSContext) -> NonZero<*mut JSObject> {
         unsafe {
             rooted!(in(cx) let obj = JS_NewPlainObject(cx));
             assert!(!obj.is_null());
-            obj.get()
+            NonZero::new(obj.get())
         }
     }
     fn SetObjectAttribute(&self, _: *mut JSContext, _: *mut JSObject) {}
@@ -208,7 +209,7 @@ impl TestBindingMethods for TestBinding {
     fn SetInterfaceAttributeWeak(&self, url: Option<&URL>) {
         self.url.set(url);
     }
-    fn GetObjectAttributeNullable(&self, _: *mut JSContext) -> *mut JSObject { ptr::null_mut() }
+    fn GetObjectAttributeNullable(&self, _: *mut JSContext) -> Option<NonZero<*mut JSObject>> { None }
     fn SetObjectAttributeNullable(&self, _: *mut JSContext, _: *mut JSObject) {}
     fn GetUnionAttributeNullable(&self) -> Option<HTMLElementOrLong> {
         Some(HTMLElementOrLong::Long(0))
@@ -257,7 +258,7 @@ impl TestBindingMethods for TestBinding {
         Blob::new(self.global().r(), BlobImpl::new_from_bytes(vec![]), "".to_owned())
     }
     fn ReceiveAny(&self, _: *mut JSContext) -> JSVal { NullValue() }
-    fn ReceiveObject(&self, cx: *mut JSContext) -> *mut JSObject {
+    fn ReceiveObject(&self, cx: *mut JSContext) -> NonZero<*mut JSObject> {
         self.ObjectAttribute(cx)
     }
     fn ReceiveUnion(&self) -> HTMLElementOrLong { HTMLElementOrLong::Long(0) }
@@ -300,7 +301,7 @@ impl TestBindingMethods for TestBinding {
     fn ReceiveNullableInterface(&self) -> Option<Root<Blob>> {
         Some(Blob::new(self.global().r(), BlobImpl::new_from_bytes(vec![]), "".to_owned()))
     }
-    fn ReceiveNullableObject(&self, cx: *mut JSContext) -> *mut JSObject {
+    fn ReceiveNullableObject(&self, cx: *mut JSContext) -> Option<NonZero<*mut JSObject>> {
         self.GetObjectAttributeNullable(cx)
     }
     fn ReceiveNullableUnion(&self) -> Option<HTMLElementOrLong> {

components/script/dom/textencoder.rs

@@ -2,6 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+use core::nonzero::NonZero;
 use dom::bindings::codegen::Bindings::TextEncoderBinding;
 use dom::bindings::codegen::Bindings::TextEncoderBinding::TextEncoderMethods;
 use dom::bindings::error::{Error, Fallible};
@@ -70,7 +71,7 @@ impl TextEncoderMethods for TextEncoder {
 
     #[allow(unsafe_code)]
     // https://encoding.spec.whatwg.org/#dom-textencoder-encode
-    fn Encode(&self, cx: *mut JSContext, input: USVString) -> *mut JSObject {
+    fn Encode(&self, cx: *mut JSContext, input: USVString) -> NonZero<*mut JSObject> {
         unsafe {
             let encoded = self.encoder.encode(&input.0, EncoderTrap::Strict).unwrap();
             let length = encoded.len() as u32;
@@ -80,7 +81,7 @@ impl TextEncoderMethods for TextEncoder {
             let js_object_data: *mut uint8_t = JS_GetUint8ArrayData(js_object.get(), &mut is_shared, ptr::null());
             assert!(!is_shared);
             ptr::copy_nonoverlapping(encoded.as_ptr(), js_object_data, length as usize);
-            js_object.get()
+            NonZero::new(js_object.get())
         }
     }
 }

components/script/dom/webglrenderingcontext.rs

@@ -3,6 +3,7 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 use canvas_traits::{CanvasCommonMsg, CanvasMsg, byte_swap};
+use core::nonzero::NonZero;
 use dom::bindings::codegen::Bindings::WebGLRenderingContextBinding::WebGLRenderingContextConstants as constants;
 use dom::bindings::codegen::Bindings::WebGLRenderingContextBinding::WebGLRenderingContextMethods;
 use dom::bindings::codegen::Bindings::WebGLRenderingContextBinding::{self, WebGLContextAttributes};
@@ -631,8 +632,9 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
     }
 
     // https://www.khronos.org/registry/webgl/specs/latest/1.0/#5.14.14
-    fn GetExtension(&self, _cx: *mut JSContext, _name: DOMString) -> *mut JSObject {
-        0 as *mut JSObject
+    fn GetExtension(&self, _cx: *mut JSContext, _name: DOMString)
+                    -> Option<NonZero<*mut JSObject>> {
+        None
     }
 
     // https://www.khronos.org/registry/webgl/specs/latest/1.0/#5.14.3

components/script/dom/xmldocument.rs

@@ -2,6 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+use core::nonzero::NonZero;
 use document_loader::DocumentLoader;
 use dom::bindings::codegen::Bindings::DocumentBinding::DocumentMethods;
 use dom::bindings::codegen::Bindings::XMLDocumentBinding::{self, XMLDocumentMethods};
@@ -87,7 +88,8 @@ impl XMLDocumentMethods for XMLDocument {
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-tree-accessors:dom-document-nameditem-filter
-    fn NamedGetter(&self, _cx: *mut JSContext, name: DOMString, found: &mut bool) -> *mut JSObject {
+    fn NamedGetter(&self, _cx: *mut JSContext, name: DOMString, found: &mut bool)
+                   -> NonZero<*mut JSObject> {
         self.upcast::<Document>().NamedGetter(_cx, name, found)
     }
 }