Bug 1851084 - remove javascript.options.weakrefs from Prefs r=mgaudet

Differential Revision: https://phabricator.services.mozilla.com/D236487

js/public/Prefs.h

@@ -106,26 +106,6 @@ class Prefs {
 #undef DEF_GETSET
 };
 
-/**
- * Specification for whether weak refs should be enabled and if so whether the
- * FinalizationRegistry.cleanupSome method should be present.
- */
-enum class WeakRefSpecifier {
-  Disabled,
-  EnabledWithCleanupSome,
-  EnabledWithoutCleanupSome
-};
-
-inline WeakRefSpecifier GetWeakRefsEnabled() {
-  if (!Prefs::weakrefs()) {
-    return WeakRefSpecifier::Disabled;
-  }
-  if (Prefs::experimental_weakrefs_expose_cleanupSome()) {
-    return WeakRefSpecifier::EnabledWithCleanupSome;
-  }
-  return WeakRefSpecifier::EnabledWithoutCleanupSome;
-}
-
 };  // namespace JS
 
 #endif /* js_Prefs_h */

js/src/fuzz-tests/tests.cpp

@@ -76,7 +76,6 @@ static void jsfuzz_uninit(JSContext* cx) {
 
 int main(int argc, char* argv[]) {
   // Override prefs for fuzz-tests.
-  JS::Prefs::setAtStartup_weakrefs(true);
   JS::Prefs::setAtStartup_experimental_weakrefs_expose_cleanupSome(true);
 
   if (!JS_Init()) {

js/src/jsapi-tests/tests.cpp

@@ -231,7 +231,6 @@ int main(int argc, char* argv[]) {
   }
 
   // Override prefs for jsapi-tests.
-  JS::Prefs::setAtStartup_weakrefs(true);
   JS::Prefs::setAtStartup_experimental_weakrefs_expose_cleanupSome(true);
 #ifdef NIGHTLY_BUILD
   JS::Prefs::setAtStartup_experimental_symbols_as_weakmap_keys(true);

js/src/shell/js.cpp

@@ -12427,7 +12427,6 @@ bool InitOptionParser(OptionParser& op) {
       !op.addBoolOption('\0', "less-debug-code",
                         "Emit less machine code for "
                         "checking assertions under DEBUG.") ||
-      !op.addBoolOption('\0', "disable-weak-refs", "Disable weak references") ||
       !op.addBoolOption('\0', "disable-tosource", "Disable toSource/uneval") ||
       !op.addBoolOption('\0', "disable-property-error-message-fix",
                         "Disable fix for the error message when accessing "
@@ -12933,9 +12932,6 @@ bool SetGlobalOptionsPreJSInit(const OptionParser& op) {
     JS::Prefs::set_experimental_json_parse_with_source(true);
   }
 
-  if (op.getBoolOption("disable-weak-refs")) {
-    JS::Prefs::setAtStartup_weakrefs(false);
-  }
   JS::Prefs::setAtStartup_experimental_weakrefs_expose_cleanupSome(true);
 
   if (op.getBoolOption("disable-destructuring-fuse")) {

js/src/tests/user.js

@@ -28,7 +28,6 @@ user_pref("privacy.trackingprotection.enabled", false);
 user_pref("privacy.trackingprotection.pbmode.enabled", false);
 user_pref("general.useragent.updates.enabled", false);
 user_pref("browser.webapps.checkForUpdates", 0);
-user_pref("javascript.options.weakrefs", true);
 user_pref("javascript.options.experimental.weakrefs.expose_cleanupSome", true);
 user_pref("javascript.options.experimental.iterator_helpers", true);
 user_pref("javascript.options.experimental.import_attributes", true);

js/src/vm/GlobalObject.cpp

@@ -169,6 +169,8 @@ bool GlobalObject::skipDeselectedConstructor(JSContext* cx, JSProtoKey key) {
     case JSProto_AsyncFunction:
     case JSProto_GeneratorFunction:
     case JSProto_AsyncGeneratorFunction:
+    case JSProto_WeakRef:
+    case JSProto_FinalizationRegistry:
       return false;
 
     case JSProto_WebAssembly:
@@ -230,10 +232,6 @@ bool GlobalObject::skipDeselectedConstructor(JSContext* cx, JSProtoKey key) {
     case JSProto_SharedArrayBuffer:
       return !cx->realm()->creationOptions().getSharedMemoryAndAtomicsEnabled();
 
-    case JSProto_WeakRef:
-    case JSProto_FinalizationRegistry:
-      return JS::GetWeakRefsEnabled() == JS::WeakRefSpecifier::Disabled;
-
     case JSProto_AsyncIterator:
       return !IsAsyncIteratorHelpersEnabled();
 

js/src/vm/JSObject.cpp

@@ -2221,8 +2221,7 @@ JS_PUBLIC_API bool js::ShouldIgnorePropertyDefinition(JSContext* cx,
   }
 
   if (key == JSProto_FinalizationRegistry &&
-      JS::GetWeakRefsEnabled() ==
-          JS::WeakRefSpecifier::EnabledWithoutCleanupSome &&
+      !JS::Prefs::experimental_weakrefs_expose_cleanupSome() &&
       id == NameToId(cx->names().cleanupSome)) {
     return true;
   }

js/xpconnect/tests/mochitest/mochitest.toml

@@ -44,7 +44,6 @@ support-files = [
   "shadow_realm_module.js",
 ]
 prefs = [
-  "javascript.options.weakrefs=true",
   "javascript.options.spectre.disable_for_isolated_content=true",
   "javascript.options.experimental.json_parse_with_source=true",
   "javascript.options.experimental.shadow_realms=true",

modules/libpref/init/StaticPrefList.yaml

@@ -8334,13 +8334,6 @@
   mirror: always
   set_spidermonkey_pref: startup
 
-# Support for weak references in JavaScript (WeakRef and FinalizationRegistry).
-- name: javascript.options.weakrefs
-  type: bool
-  value: true
-  mirror: always
-  set_spidermonkey_pref: startup
-
 # Whether to expose the FinalizationRegistry.prototype.cleanupSome method.
 - name: javascript.options.experimental.weakrefs.expose_cleanupSome
   type: bool