Describe non-callback interface objects with JSClass structures

JS_NewFunction doesn't allow us to set the prototype of the interface objects.

components/script/dom/bindings/interface.rs

@@ -4,17 +4,109 @@
 
 //! Machinery to initialise interface prototype objects and interface objects.
 
+use dom::bindings::codegen::PrototypeList;
+use dom::bindings::conversions::get_dom_class;
 use dom::bindings::utils::{ConstantSpec, NonNullJSNative, define_constants};
-use js::jsapi::{HandleObject, JSClass, JSContext, JSFunctionSpec};
-use js::jsapi::{JSObject, JSPropertySpec, JS_DefineProperty1, JS_DefineProperty2};
-use js::jsapi::{JS_GetFunctionObject, JS_InternString, JS_LinkConstructorAndPrototype};
-use js::jsapi::{JS_NewFunction, JS_NewObject, JS_NewObjectWithUniqueType};
-use js::jsapi::{MutableHandleObject, RootedObject, RootedString};
+use js::glue::UncheckedUnwrapObject;
+use js::jsapi::{Class, ClassExtension, ClassSpec, HandleObject, HandleValue, JSClass};
+use js::jsapi::{JSContext, JSFunctionSpec, JSObject, JSPropertySpec, JSString};
+use js::jsapi::{JS_DefineProperty1, JS_DefineProperty2, JS_DefineProperty4};
+use js::jsapi::{JS_GetFunctionObject, JS_GetPrototype, JS_InternString};
+use js::jsapi::{JS_LinkConstructorAndPrototype, JS_NewFunction, JS_NewObject};
+use js::jsapi::{JS_NewObjectWithUniqueType, MutableHandleObject, MutableHandleValue};
+use js::jsapi::{ObjectOps, RootedObject, RootedString, Value};
 use js::rust::{define_methods, define_properties};
 use js::{JSFUN_CONSTRUCTOR, JSPROP_PERMANENT, JSPROP_READONLY};
 use libc;
 use std::ptr;
 
+/// A constructor class hook.
+pub type ConstructorClassHook =
+    unsafe extern "C" fn(cx: *mut JSContext, argc: u32, vp: *mut Value) -> bool;
+
+/// A has_instance class hook.
+pub type HasInstanceClassHook =
+    unsafe extern "C" fn(cx: *mut JSContext,
+                         obj: HandleObject,
+                         vp: MutableHandleValue,
+                         bp: *mut bool)
+                         -> bool;
+
+/// A fun_to_string class hook.
+pub type FunToStringHook =
+    unsafe extern "C" fn(cx: *mut JSContext,
+                         obj: HandleObject,
+                         indent: u32)
+                         -> *mut JSString;
+
+/// The class of a non-callback interface object.
+#[derive(Copy, Clone)]
+pub struct NonCallbackInterfaceObjectClass {
+    /// The SpiderMonkey Class structure.
+    pub class: Class,
+}
+unsafe impl Sync for NonCallbackInterfaceObjectClass {}
+
+impl NonCallbackInterfaceObjectClass {
+    /// Create a new `NonCallbackInterfaceObjectClass` structure.
+    pub const fn new(
+            constructor: ConstructorClassHook,
+            has_instance: HasInstanceClassHook,
+            fun_to_string: FunToStringHook)
+            -> NonCallbackInterfaceObjectClass {
+        NonCallbackInterfaceObjectClass {
+            class: Class {
+                name: b"Function\0" as *const _ as *const libc::c_char,
+                flags: 0,
+                addProperty: None,
+                delProperty: None,
+                getProperty: None,
+                setProperty: None,
+                enumerate: None,
+                resolve: None,
+                convert: None,
+                finalize: None,
+                call: Some(constructor),
+                hasInstance: Some(has_instance),
+                construct: Some(constructor),
+                trace: None,
+                spec: ClassSpec {
+                    createConstructor: None,
+                    createPrototype: None,
+                    constructorFunctions: ptr::null(),
+                    constructorProperties: ptr::null(),
+                    prototypeFunctions: ptr::null(),
+                    prototypeProperties: ptr::null(),
+                    finishInit: None,
+                    flags: 0,
+                },
+                ext: ClassExtension {
+                    outerObject: None,
+                    innerObject: None,
+                    isWrappedNative: false,
+                    weakmapKeyDelegateOp: None,
+                    objectMovedOp: None,
+                },
+                ops: ObjectOps {
+                    lookupProperty: None,
+                    defineProperty: None,
+                    hasProperty: None,
+                    getProperty: None,
+                    setProperty: None,
+                    getOwnPropertyDescriptor: None,
+                    deleteProperty: None,
+                    watch: None,
+                    unwatch: None,
+                    getElements: None,
+                    enumerate: None,
+                    thisObject: None,
+                    funToString: Some(fun_to_string),
+                }
+            },
+        }
+    }
+}
+
 /// Create and define the interface object of a callback interface.
 pub unsafe fn create_callback_interface_object(
         cx: *mut JSContext,
@@ -45,31 +137,26 @@ pub unsafe fn create_interface_prototype_object(
 pub unsafe fn create_noncallback_interface_object(
         cx: *mut JSContext,
         receiver: HandleObject,
-        constructor_native: NonNullJSNative,
+        proto: HandleObject,
+        class: &'static NonCallbackInterfaceObjectClass,
         static_methods: Option<&'static [JSFunctionSpec]>,
         static_properties: Option<&'static [JSPropertySpec]>,
         constants: &'static [ConstantSpec],
         interface_prototype_object: HandleObject,
         name: &'static [u8],
         length: u32) {
-    assert!(!interface_prototype_object.ptr.is_null());
-
-    let interface_object =
-        RootedObject::new(cx, create_constructor(cx, constructor_native, length, name));
-    assert!(!interface_object.ptr.is_null());
-
-    if let Some(static_methods) = static_methods {
-        define_methods(cx, interface_object.handle(), static_methods).unwrap();
-    }
-
-    if let Some(static_properties) = static_properties {
-        define_properties(cx, interface_object.handle(), static_properties).unwrap();
-    }
-
-    define_constants(cx, interface_object.handle(), constants);
-
+    let mut interface_object = RootedObject::new(cx, ptr::null_mut());
+    create_object(cx,
+                  proto,
+                  &*(class as *const _ as *const JSClass),
+                  static_methods,
+                  static_properties,
+                  constants,
+                  interface_object.handle_mut());
     assert!(JS_LinkConstructorAndPrototype(cx, interface_object.handle(),
                                            interface_prototype_object));
+    define_name(cx, interface_object.handle(), name);
+    define_length(cx, interface_object.handle(), length);
     define_on_global_object(cx, receiver, name, interface_object.handle());
 }
 
@@ -99,6 +186,43 @@ pub unsafe fn create_named_constructors(
     }
 }
 
+/// Return whether a value is an instance of a given prototype.
+/// http://heycam.github.io/webidl/#es-interface-hasinstance
+pub unsafe fn has_instance(
+        cx: *mut JSContext,
+        prototype: HandleObject,
+        value: HandleValue,
+        id: PrototypeList::ID,
+        index: usize)
+        -> Result<bool, ()> {
+    if !value.is_object() {
+        // Step 1.
+        return Ok(false);
+    }
+    let mut value = RootedObject::new(cx, value.to_object());
+
+    // Steps 2-3 only concern callback interface objects.
+
+    if let Ok(dom_class) = get_dom_class(UncheckedUnwrapObject(value.ptr, /* stopAtOuter = */ 0)) {
+        if dom_class.interface_chain[index] == id {
+            // Step 4.
+            return Ok(true);
+        }
+    }
+
+    while JS_GetPrototype(cx, value.handle(), value.handle_mut()) {
+        if value.ptr.is_null() {
+            // Step 5.2.
+            return Ok(false);
+        } else if value.ptr as *const _ == prototype.ptr {
+            // Step 5.3.
+            return Ok(true);
+        }
+    }
+    // JS_GetPrototype threw an exception.
+    Err(())
+}
+
 unsafe fn create_constructor(
         cx: *mut JSContext,
         constructor_native: NonNullJSNative,
@@ -152,6 +276,15 @@ unsafe fn define_name(cx: *mut JSContext, obj: HandleObject, name: &'static [u8]
                                None, None));
 }
 
+unsafe fn define_length(cx: *mut JSContext, obj: HandleObject, length: u32) {
+    assert!(JS_DefineProperty4(cx,
+                               obj,
+                               b"length\0".as_ptr() as *const libc::c_char,
+                               length,
+                               JSPROP_READONLY,
+                               None, None));
+}
+
 unsafe fn define_on_global_object(
         cx: *mut JSContext,
         receiver: HandleObject,