Auto merge of #25446 - pshaughn:fixme11868, r=jdm

Make getOwnPropertyDescriptor hold the correct value for indexed/named properties

This is towards #25036 and #25415; it could have far-reaching implications so I want to test it in isolation and see the results on the full test suite.

A few lines of code had a FIXME(#11868) despite that issue being closed, and looking for the pattern that was marked that way, I found one other unmarked instance of it. It doesn't immediately crash, and maybe it will pass some tests or fail some tests in informative ways.

EDIT: After adding an overlooked extended attribute to HTMLFormElement, this works very well indeed and seems to be worth merging!

---
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- [X] These changes fix #25036

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8 files changed, 6 insertions, 30 deletions

diff --git a/components/script/dom/bindings/codegen/CodegenRust.py b/components/script/dom/bindings/codegen/CodegenRust.py
index e0a5df68882..d79bc073e76 100644
--- a/components/script/dom/bindings/codegen/CodegenRust.py
+++ b/components/script/dom/bindings/codegen/CodegenRust.py
@@ -5147,8 +5147,7 @@ class CGDOMJSProxyHandler_getOwnPropertyDescriptor(CGAbstractExternMethod):
             attrs = "JSPROP_ENUMERATE"
             if self.descriptor.operations['IndexedSetter'] is None:
                 attrs += " | JSPROP_READONLY"
-            # FIXME(#11868) Should assign to desc.value, desc.get() is a copy.
-            fillDescriptor = ("desc.get().value = result_root.get();\n"
+            fillDescriptor = ("desc.value = result_root.get();\n"
                               "fill_property_descriptor(MutableHandle::from_raw(desc), proxy.get(), (%s) as u32);\n"
                               "return true;" % attrs)
             templateValues = {
@@ -5173,8 +5172,7 @@ class CGDOMJSProxyHandler_getOwnPropertyDescriptor(CGAbstractExternMethod):
                 attrs = " | ".join(attrs)
             else:
                 attrs = "0"
-            # FIXME(#11868) Should assign to desc.value, desc.get() is a copy.
-            fillDescriptor = ("desc.get().value = result_root.get();\n"
+            fillDescriptor = ("desc.value = result_root.get();\n"
                               "fill_property_descriptor(MutableHandle::from_raw(desc), proxy.get(), (%s) as u32);\n"
                               "return true;" % attrs)
             templateValues = {
@@ -5221,7 +5219,7 @@ if !expando.is_null() {
     }
 }
 """ + namedGet + """\
-desc.get().obj = ptr::null_mut();
+desc.obj = ptr::null_mut();
 return true;"""
 
     def definition_body(self):
diff --git a/components/script/dom/webidls/HTMLFormElement.webidl b/components/script/dom/webidls/HTMLFormElement.webidl
index 13ffbf4dfe8..744f6d84ca9 100644
--- a/components/script/dom/webidls/HTMLFormElement.webidl
+++ b/components/script/dom/webidls/HTMLFormElement.webidl
@@ -3,7 +3,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 // https://html.spec.whatwg.org/multipage/#htmlformelement
-[Exposed=Window]
+[Exposed=Window, LegacyUnenumerableNamedProperties]
 interface HTMLFormElement : HTMLElement {
   [HTMLConstructor] constructor();
 
diff --git a/components/script/dom/webidls/Window.webidl b/components/script/dom/webidls/Window.webidl
index f2cdeeb18a5..afd5183de33 100644
--- a/components/script/dom/webidls/Window.webidl
+++ b/components/script/dom/webidls/Window.webidl
@@ -3,7 +3,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 // https://html.spec.whatwg.org/multipage/#window
-[Global=Window, Exposed=Window]
+[Global=Window, Exposed=Window /*, LegacyUnenumerableNamedProperties */]
 /*sealed*/ interface Window : GlobalScope {
   // the current browsing context
   [Unforgeable] readonly attribute WindowProxy window;
diff --git a/components/script/dom/windowproxy.rs b/components/script/dom/windowproxy.rs
index 7fea1728c12..6aa0b9244cf 100644
--- a/components/script/dom/windowproxy.rs
+++ b/components/script/dom/windowproxy.rs
@@ -822,8 +822,7 @@ unsafe extern "C" fn getOwnPropertyDescriptor(
 
     assert!(desc.obj.is_null() || desc.obj == target.get());
     if desc.obj == target.get() {
-        // FIXME(#11868) Should assign to desc.obj, desc.get() is a copy.
-        desc.get().obj = proxy.get();
+        desc.obj = proxy.get();
     }
 
     true
diff --git a/tests/wpt/metadata/WebIDL/ecmascript-binding/legacy-platform-object.html.ini b/tests/wpt/metadata/WebIDL/ecmascript-binding/legacy-platform-object.html.ini
index a2250466733..0ba8ad10aaa 100644
--- a/tests/wpt/metadata/WebIDL/ecmascript-binding/legacy-platform-object.html.ini
+++ b/tests/wpt/metadata/WebIDL/ecmascript-binding/legacy-platform-object.html.ini
@@ -1,14 +1,5 @@
 [legacy-platform-object.html]
   type: testharness
-  [[[GetOwnProperty\]\] with getters and no setters]
-    expected: FAIL
-
-  [[[GetOwnProperty\]\] with named property getters and setters]
-    expected: FAIL
-
-  [[[GetOwnProperty\]\] with indexed property getters and setters]
-    expected: FAIL
-
   [Test [[DefineOwnProperty\]\] with no indexed property setter support.]
     expected: FAIL
 
diff --git a/tests/wpt/metadata/dom/collections/HTMLCollection-supported-property-indices.html.ini b/tests/wpt/metadata/dom/collections/HTMLCollection-supported-property-indices.html.ini
index 4bf756bec94..16ea183e3c0 100644
--- a/tests/wpt/metadata/dom/collections/HTMLCollection-supported-property-indices.html.ini
+++ b/tests/wpt/metadata/dom/collections/HTMLCollection-supported-property-indices.html.ini
@@ -6,6 +6,3 @@
   [Trying to set an expando with an indexed property name past the end of the list]
     expected: FAIL
 
-  [Trying to delete an indexed property name should never work]
-    expected: FAIL
-
diff --git a/tests/wpt/metadata/html/dom/elements/global-attributes/dataset-binding.window.js.ini b/tests/wpt/metadata/html/dom/elements/global-attributes/dataset-binding.window.js.ini
index 19996050bff..1fcfb3b5887 100644
--- a/tests/wpt/metadata/html/dom/elements/global-attributes/dataset-binding.window.js.ini
+++ b/tests/wpt/metadata/html/dom/elements/global-attributes/dataset-binding.window.js.ini
@@ -5,9 +5,3 @@
   [Setting property for key 9 with accessor property on prototype]
     expected: FAIL
 
-  [Getting property descriptor for key 9]
-    expected: FAIL
-
-  [Getting property descriptor for key x]
-    expected: FAIL
-
diff --git a/tests/wpt/metadata/html/semantics/forms/the-form-element/form-nameditem.html.ini b/tests/wpt/metadata/html/semantics/forms/the-form-element/form-nameditem.html.ini
index 2fc5417441d..b33041d0dc6 100644
--- a/tests/wpt/metadata/html/semantics/forms/the-form-element/form-nameditem.html.ini
+++ b/tests/wpt/metadata/html/semantics/forms/the-form-element/form-nameditem.html.ini
@@ -1,8 +1,5 @@
 [form-nameditem.html]
   type: testharness
-  [Name for a single element should work]
-    expected: FAIL
-
   [All listed elements except input type=image should be present in the form]
     expected: FAIL