Initial implementation of ownPropertyKeys proxy handler

Generates `SupportedPropertyNames` on DOM structs that should implement
it. Most of them are unimplemented now (which can be implemented in
later PRs), with the exception of `HTMLCollection`. Also added a couple
relevant WPT tests.

Closes servo#6390

Closes servo#2215

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

@@ -2472,7 +2472,7 @@ def definition_body(self):
     enter: None,
     getOwnPropertyDescriptor: Some(getOwnPropertyDescriptor),
     defineProperty: Some(%s),
-    ownPropertyKeys: Some(proxyhandler::own_property_keys),
+    ownPropertyKeys: Some(own_property_keys),
     delete_: Some(%s),
     enumerate: None,
     preventExtensions: Some(proxyhandler::prevent_extensions),
@@ -4177,6 +4177,60 @@ def definition_body(self):
         return CGGeneric(self.getBody())
 
 
+class CGDOMJSProxyHandler_ownPropertyKeys(CGAbstractExternMethod):
+    def __init__(self, descriptor):
+        args = [Argument('*mut JSContext', 'cx'),
+                Argument('HandleObject', 'proxy'),
+                Argument('*mut AutoIdVector', 'props')]
+        CGAbstractExternMethod.__init__(self, descriptor, "own_property_keys", "u8", args)
+        self.descriptor = descriptor
+
+    def getBody(self):
+        body = dedent(
+            """
+            let unwrapped_proxy = UnwrapProxy(proxy);
+            """)
+
+        if self.descriptor.operations['IndexedGetter']:
+            body += dedent(
+                """
+                for i in 0..(*unwrapped_proxy).Length() {
+                    let rooted_jsid = RootedId::new(cx, int_to_jsid(i as i32));
+                    AppendToAutoIdVector(props, rooted_jsid.handle().get());
+                }
+                """)
+
+        if self.descriptor.operations['NamedGetter']:
+            body += dedent(
+                """
+                for name in (*unwrapped_proxy).SupportedPropertyNames() {
+                    let cstring = CString::new(name).unwrap();
+                    let jsstring = JS_InternString(cx, cstring.as_ptr());
+                    let mut rooted = RootedString::new(cx, jsstring);
+                    let jsid = INTERNED_STRING_TO_JSID(cx, rooted.handle().get());
+                    let rooted_jsid = RootedId::new(cx, jsid);
+                    AppendToAutoIdVector(props, rooted_jsid.handle().get());
+                }
+                """)
+
+        body += dedent(
+            """
+            let expando = get_expando_object(proxy);
+            if !expando.is_null() {
+                let rooted_expando = RootedObject::new(cx, expando);
+                // FIXME: remove the magic hex numbers below: https://github.com/servo/servo/issues/7278
+                GetPropertyKeys(cx, rooted_expando.handle(), 0x8 | 0x10 | 0x20, props);
+            }
+
+            return JSTrue;
+            """)
+
+        return body
+
+    def definition_body(self):
+        return CGGeneric(self.getBody())
+
+
 class CGDOMJSProxyHandler_hasOwn(CGAbstractExternMethod):
     def __init__(self, descriptor):
         args = [Argument('*mut JSContext', 'cx'), Argument('HandleObject', 'proxy'),
@@ -4495,6 +4549,14 @@ def members():
                     infallible = 'infallible' in descriptor.getExtendedAttributes(operation)
                     if operation.isGetter():
                         arguments = method_arguments(descriptor, rettype, arguments, trailing=("found", "&mut bool"))
+
+                        # If this interface 'supports named properties', then we
+                        # should be able to access 'supported property names'
+                        #
+                        # WebIDL, Second Draft, section 3.2.4.5
+                        # https://heycam.github.io/webidl/#idl-named-properties
+                        if operation.isNamed():
+                            yield "SupportedPropertyNames", [], "Vec<DOMString>"
                     else:
                         arguments = method_arguments(descriptor, rettype, arguments)
                     rettype = return_type(descriptor, rettype, infallible)
@@ -4599,6 +4661,7 @@ def __init__(self, descriptor):
                 # cgThings.append(CGProxyIsProxy(descriptor))
                 cgThings.append(CGProxyUnwrap(descriptor))
                 cgThings.append(CGDOMJSProxyHandlerDOMClass(descriptor))
+                cgThings.append(CGDOMJSProxyHandler_ownPropertyKeys(descriptor))
                 cgThings.append(CGDOMJSProxyHandler_getOwnPropertyDescriptor(descriptor))
                 cgThings.append(CGDOMJSProxyHandler_className(descriptor))
                 cgThings.append(CGDOMJSProxyHandler_get(descriptor))
@@ -4962,20 +5025,22 @@ def __init__(self, config, prefix, webIDLFile):
             'js::jsapi::{JSClass, FreeOp, JSFreeOp, JSFunctionSpec, jsid}',
             'js::jsapi::{MutableHandleValue, MutableHandleObject, HandleObject, HandleValue, RootedObject}',
             'js::jsapi::{RootedValue, JSNativeWrapper, JSNative, JSObject, JSPropertyDescriptor}',
+            'js::jsapi::{RootedId, JS_InternString, RootedString, INTERNED_STRING_TO_JSID}',
             'js::jsapi::{JSPropertySpec}',
             'js::jsapi::{JSString, JSTracer, JSJitInfo, JSJitInfo_OpType, JSJitInfo_AliasSet}',
             'js::jsapi::{MutableHandle, Handle, HandleId, JSType, JSValueType}',
             'js::jsapi::{SymbolCode, ObjectOpResult, HandleValueArray}',
             'js::jsapi::{JSJitGetterCallArgs, JSJitSetterCallArgs, JSJitMethodCallArgs, CallArgs}',
             'js::jsapi::{JSAutoCompartment, JSAutoRequest, JS_ComputeThis}',
-            'js::jsapi::GetGlobalForObjectCrossCompartment',
+            'js::jsapi::{GetGlobalForObjectCrossCompartment, AutoIdVector}',
             'js::jsval::JSVal',
             'js::jsval::{ObjectValue, ObjectOrNullValue, PrivateValue}',
             'js::jsval::{NullValue, UndefinedValue}',
             'js::glue::{CallJitMethodOp, CallJitGetterOp, CallJitSetterOp, CreateProxyHandler}',
             'js::glue::{GetProxyPrivate, NewProxyObject, ProxyTraps}',
             'js::glue::{RUST_FUNCTION_VALUE_TO_JITINFO}',
-            'js::glue::{RUST_JS_NumberValue, RUST_JSID_IS_STRING}',
+            'js::glue::{RUST_JS_NumberValue, RUST_JSID_IS_STRING, int_to_jsid}',
+            'js::glue::{AppendToAutoIdVector, GetPropertyKeys}',
             'js::rust::GCMethods',
             'js::{JSTrue, JSFalse}',
             'dom::bindings',

components/script/dom/bindings/proxyhandler.rs

@@ -13,7 +13,6 @@ use js::jsapi::{JS_GetPropertyDescriptorById};
 use js::jsapi::{JS_DefinePropertyById6, JS_NewObjectWithGivenProto};
 use js::jsapi::{JS_StrictPropertyStub, JSErrNum};
 use js::jsapi::{Handle, HandleObject, HandleId, MutableHandle, RootedObject, ObjectOpResult};
-use js::jsapi::AutoIdVector;
 use js::jsapi::GetObjectProto;
 use js::jsval::ObjectValue;
 use js::glue::GetProxyExtra;
@@ -83,15 +82,6 @@ pub unsafe extern fn delete(cx: *mut JSContext, proxy: HandleObject, id: HandleI
     delete_property_by_id(cx, expando.handle(), id, bp)
 }
 
-/// Stub for ownPropertyKeys
-pub unsafe extern fn own_property_keys(_cx: *mut JSContext,
-                                       _proxy: HandleObject,
-                                       _props: *mut AutoIdVector) -> u8 {
-    // FIXME: implement this
-    // https://github.com/servo/servo/issues/6390
-    JSTrue
-}
-
 /// Controls whether the Extensible bit can be changed
 pub unsafe extern fn prevent_extensions(_cx: *mut JSContext,
                                         _proxy: HandleObject,

components/script/dom/document.rs

@@ -1912,6 +1912,12 @@ impl<'a> DocumentMethods for &'a Document {
         collection.r().reflector().get_jsobject().get()
     }
 
+    // https://html.spec.whatwg.org/#document
+    fn SupportedPropertyNames(self) -> Vec<DOMString> {
+        // FIXME: unimplemented
+        vec![]
+    }
+
     global_event_handlers!();
     event_handler!(readystatechange, GetOnreadystatechange, SetOnreadystatechange);
 }

components/script/dom/domstringmap.rs

@@ -67,5 +67,10 @@ impl<'a> DOMStringMapMethods for &'a DOMStringMap {
             }
         }
     }
-}
 
+    // https://html.spec.whatwg.org/multipage/#domstringmap
+    fn SupportedPropertyNames(self) -> Vec<DOMString> {
+        // FIXME: unimplemented
+        vec![]
+    }
+}

components/script/dom/htmlcollection.rs

@@ -227,5 +227,30 @@ impl<'a> HTMLCollectionMethods for &'a HTMLCollection {
         *found = maybe_elem.is_some();
         maybe_elem
     }
-}
 
+    // https://dom.spec.whatwg.org/#interface-htmlcollection
+    fn SupportedPropertyNames(self) -> Vec<DOMString> {
+        // Step 1
+        let mut result = vec![];
+
+        // Step 2
+        let ref filter = self.collection.1;
+        let root = self.collection.0.root();
+        let elems = HTMLCollection::traverse(root.r()).filter(|element| filter.filter(element.r(), root.r()));
+        for elem in elems {
+            // Step 2.1
+            let id_attr = elem.get_string_attribute(&atom!("id"));
+            if !id_attr.is_empty() && !result.contains(&id_attr) {
+                result.push(id_attr)
+            }
+            // Step 2.2
+            let name_attr = elem.get_string_attribute(&atom!("name"));
+            if !name_attr.is_empty() && !result.contains(&name_attr) && *elem.namespace() == ns!(HTML) {
+                result.push(name_attr)
+            }
+        }
+
+        // Step 3
+        result
+    }
+}

components/script/dom/namednodemap.rs

@@ -105,5 +105,9 @@ impl<'a> NamedNodeMapMethods for &'a NamedNodeMap {
         *found = item.is_some();
         item
     }
-}
 
+    fn SupportedPropertyNames(self) -> Vec<DOMString> {
+        // FIXME: unimplemented
+        vec![]
+    }
+}

components/script/dom/storage.rs

@@ -134,6 +134,11 @@ impl<'a> StorageMethods for &'a Storage {
     fn NamedDeleter(self, name: DOMString) {
         self.RemoveItem(name);
     }
+
+    fn SupportedPropertyNames(self) -> Vec<DOMString> {
+        // FIXME: unimplemented
+        vec![]
+    }
 }
 
 trait PrivateStorageHelpers {

components/script/dom/testbindingproxy.rs

@@ -16,7 +16,8 @@ pub struct TestBindingProxy {
 }
 
 impl<'a> TestBindingProxyMethods for &'a TestBindingProxy {
-
+    fn Length(self) -> u32 {0}
+    fn SupportedPropertyNames(self) -> Vec<DOMString> {vec![]}
     fn GetNamedItem(self, _: DOMString) -> DOMString {"".to_owned()}
     fn SetNamedItem(self, _: DOMString, _: DOMString) -> () {}
     fn GetItem(self, _: u32) -> DOMString {"".to_owned()}

components/script/dom/webidls/TestBindingProxy.webidl

@@ -13,6 +13,7 @@
 // web pages.
 
 interface TestBindingProxy : TestBinding {
+  readonly attribute unsigned long length;
 
   getter DOMString getNamedItem(DOMString name);
 

tests/wpt/metadata/MANIFEST.json

@@ -13071,6 +13071,10 @@
         "path": "dom/collections/HTMLCollection-empty-name.html",
         "url": "/dom/collections/HTMLCollection-empty-name.html"
       },
+      {
+        "path": "dom/collections/HTMLCollection-supported-property-names.html",
+        "url": "/dom/collections/HTMLCollection-supported-property-names.html"
+      },
       {
         "path": "dom/events/Event-constants.html",
         "url": "/dom/events/Event-constants.html"
@@ -18071,6 +18075,10 @@
         "path": "js/builtins/Object.prototype.freeze.html",
         "url": "/js/builtins/Object.prototype.freeze.html"
       },
+      {
+        "path": "js/builtins/Object.prototype.getOwnPropertyNames.html",
+        "url": "/js/builtins/Object.prototype.getOwnPropertyNames.html"
+      },
       {
         "path": "js/builtins/Object.prototype.hasOwnProperty-order.html",
         "url": "/js/builtins/Object.prototype.hasOwnProperty-order.html"

tests/wpt/web-platform-tests/dom/collections/HTMLCollection-supported-property-names.html

@@ -0,0 +1,56 @@
+<!doctype html>
+<meta charset=utf-8>
+<link rel=help href=https://dom.spec.whatwg.org/#interface-htmlcollection>
+<script src=/resources/testharness.js></script>
+<script src=/resources/testharnessreport.js></script>
+
+<div id=log></div>
+
+<!-- with no attribute -->
+<span></span>
+
+<!-- with `id` attribute -->
+<span id=''></span>
+<span id='some-id'></span>
+<span id='some-id'></span><!-- to ensure no duplicates -->
+
+<!-- with `name` attribute -->
+<span name=''></span>
+<span name='some-name'></span>
+<span name='some-name'></span><!-- to ensure no duplicates -->
+
+<!-- with `name` and `id` attribute -->
+<span id='another-id' name='another-name'></span>
+
+<script>
+test(function () {
+  var elements = document.getElementsByTagName("span");
+  assert_array_equals(
+    Object.getOwnPropertyNames(elements),
+    ['0', '1', '2', '3', '4', '5', '6', '7', 'some-id', 'some-name', 'another-id', 'another-name']
+  );
+}, 'Object.getOwnPropertyNames on HTMLCollection');
+
+test(function () {
+  var elem = document.createElementNS('some-random-namespace', 'foo');
+  elem.setAttribute("name", "some-name");
+  document.body.appendChild(elem);
+
+  var elements = document.getElementsByTagName("foo");
+  assert_array_equals(Object.getOwnPropertyNames(elements), ['0']);
+
+  elem.remove();
+}, 'Object.getOwnPropertyNames on HTMLCollection with non-HTML namespace');
+
+test(function () {
+  var elem = document.createElement('foo');
+  document.body.appendChild(elem);
+
+  var elements = document.getElementsByTagName("foo");
+  elements.someProperty = "some value";
+
+  assert_array_equals(Object.getOwnPropertyNames(elements), ['0', 'someProperty']);
+
+  elem.remove();
+}, 'Object.getOwnPropertyNames on HTMLCollection with expando object');
+</script>

tests/wpt/web-platform-tests/js/builtins/Object.prototype.getOwnPropertyNames.html

@@ -0,0 +1,56 @@
+<!doctype html>
+<title>Object.prototype.getOwnPropertyNames</title>
+<link rel=help href=http://es5.github.io/#x15.2.3.4>
+<script src=/resources/testharness.js></script>
+<script src=/resources/testharnessreport.js></script>
+
+<div id=log></div>
+<script>
+test(function () {
+  var obj = {0: 'a', 1: 'b', 2: 'c'};
+  assert_array_equals(
+    Object.getOwnPropertyNames(obj).sort(),
+    ['0', '1', '2']
+  );
+}, "object");
+
+test(function () {
+  var arr = ['a', 'b', 'c'];
+  assert_array_equals(
+    Object.getOwnPropertyNames(arr).sort(),
+    ['0', '1', '2', 'length']
+  );
+}, "array-like");
+
+test(function () {
+  var obj = Object.create({}, {
+    getFoo: {
+      value: function() { return this.foo; },
+      enumerable: false
+    }
+  });
+  obj.foo = 1;
+  assert_array_equals(
+    Object.getOwnPropertyNames(obj).sort(),
+    ['foo', 'getFoo']
+  );
+}, "non-enumerable property");
+
+test(function() {
+  function ParentClass() {}
+  ParentClass.prototype.inheritedMethod = function() {};
+
+  function ChildClass() {
+    this.prop = 5;
+    this.method = function() {};
+  }
+  ChildClass.prototype = new ParentClass;
+  ChildClass.prototype.prototypeMethod = function() {};
+
+  var obj = new ChildClass;
+  assert_array_equals(
+    Object.getOwnPropertyNames(obj).sort(),
+    ['method', 'prop']
+  );
+}, 'items on the prototype chain are not listed');
+</script>