Bug 1865406 - Use JS::Prefs to add browser preference r=jandem

Even though it supports adding preferences to JS Shell, I kept the custom
`--enable-json-parse-with-source` because it makes the shell-option flags very
slightly easier in jstests.

Differential Revision: https://phabricator.services.mozilla.com/D202615

js/public/RealmOptions.h

@@ -178,14 +178,6 @@ class JS_PUBLIC_API RealmCreationOptions {
     return *this;
   }
 
-#ifdef ENABLE_JSON_PARSE_WITH_SOURCE
-  bool getJSONParseWithSource() const { return jsonParseWithSource; }
-  RealmCreationOptions& setJSONParseWithSource(bool flag) {
-    jsonParseWithSource = flag;
-    return *this;
-  }
-#endif
-
   // This flag doesn't affect JS engine behavior.  It is used by Gecko to
   // mark whether content windows and workers are "Secure Context"s. See
   // https://w3c.github.io/webappsec-secure-contexts/
@@ -246,9 +238,6 @@ class JS_PUBLIC_API RealmCreationOptions {
   bool defineSharedArrayBufferConstructor_ = true;
   bool coopAndCoep_ = false;
   bool toSource_ = false;
-#ifdef ENABLE_JSON_PARSE_WITH_SOURCE
-  bool jsonParseWithSource = false;
-#endif
 
   bool secureContext_ = false;
   bool freezeBuiltins_ = false;

js/src/builtin/JSON.cpp

@@ -24,6 +24,7 @@
 #include "js/friend/ErrorMessages.h"  // js::GetErrorMessage, JSMSG_*
 #include "js/friend/StackLimits.h"    // js::AutoCheckRecursionLimit
 #include "js/Object.h"                // JS::GetBuiltinClass
+#include "js/Prefs.h"                 // JS::Prefs
 #include "js/PropertySpec.h"
 #include "js/StableStringChars.h"
 #include "js/TypeDecls.h"
@@ -1768,7 +1769,7 @@ static bool InternalizeJSONProperty(
 #ifdef ENABLE_JSON_PARSE_WITH_SOURCE
   RootedObject context(cx);
   Rooted<UniquePtr<ParseRecordObject::EntryMap>> entries(cx);
-  if (cx->realm()->creationOptions().getJSONParseWithSource()) {
+  if (JS::Prefs::experimental_json_parse_with_source()) {
     // https://tc39.es/proposal-json-parse-with-source/#sec-internalizejsonproperty
     bool sameVal = false;
     Rooted<Value> parsedValue(cx, parseRecord.get().value);
@@ -1919,7 +1920,7 @@ static bool InternalizeJSONProperty(
 
   RootedValue keyVal(cx, StringValue(key));
 #ifdef ENABLE_JSON_PARSE_WITH_SOURCE
-  if (cx->realm()->creationOptions().getJSONParseWithSource()) {
+  if (JS::Prefs::experimental_json_parse_with_source()) {
     RootedValue contextVal(cx, ObjectValue(*context));
     return js::Call(cx, reviver, holder, keyVal, val, contextVal, vp);
   }
@@ -1940,7 +1941,7 @@ static bool Revive(JSContext* cx, HandleValue reviver,
   }
 
 #ifdef ENABLE_JSON_PARSE_WITH_SOURCE
-  MOZ_ASSERT_IF(cx->realm()->creationOptions().getJSONParseWithSource(),
+  MOZ_ASSERT_IF(JS::Prefs::experimental_json_parse_with_source(),
                 pro.get().value == vp.get());
 #endif
   Rooted<jsid> id(cx, NameToId(cx->names().empty_));
@@ -1962,8 +1963,7 @@ bool js::ParseJSONWithReviver(JSContext* cx,
   /* https://262.ecma-international.org/14.0/#sec-json.parse steps 2-10. */
   Rooted<ParseRecordObject> pro(cx);
 #ifdef ENABLE_JSON_PARSE_WITH_SOURCE
-  if (cx->realm()->creationOptions().getJSONParseWithSource() &&
-      IsCallable(reviver)) {
+  if (JS::Prefs::experimental_json_parse_with_source() && IsCallable(reviver)) {
     Rooted<JSONReviveParser<CharT>> parser(cx, cx, chars);
     if (!parser.get().parse(vp, &pro)) {
       return false;

js/src/shell/js.cpp

@@ -729,9 +729,6 @@ bool shell::enableSourcePragmas = true;
 bool shell::enableAsyncStacks = false;
 bool shell::enableAsyncStackCaptureDebuggeeOnly = false;
 bool shell::enableToSource = false;
-#ifdef ENABLE_JSON_PARSE_WITH_SOURCE
-bool shell::enableJSONParseWithSource = false;
-#endif
 bool shell::enableImportAttributes = false;
 bool shell::enableImportAttributesAssertSyntax = false;
 #ifdef JS_GC_ZEAL
@@ -4123,11 +4120,7 @@ static void SetStandardRealmOptions(JS::RealmOptions& options) {
   options.creationOptions()
       .setSharedMemoryAndAtomicsEnabled(enableSharedMemory)
       .setCoopAndCoepEnabled(false)
-      .setToSourceEnabled(enableToSource)
-#ifdef ENABLE_JSON_PARSE_WITH_SOURCE
-      .setJSONParseWithSource(enableJSONParseWithSource)
-#endif
-      ;
+      .setToSourceEnabled(enableToSource);
 }
 
 [[nodiscard]] static bool CheckRealmOptions(JSContext* cx,
@@ -12430,6 +12423,14 @@ bool SetGlobalOptionsPreJSInit(const OptionParser& op) {
     JS::Prefs::setAtStartup_experimental_uint8array_base64(true);
   }
 #endif
+#ifdef ENABLE_JSON_PARSE_WITH_SOURCE
+  JS::Prefs::setAtStartup_experimental_json_parse_with_source(
+      op.getBoolOption("enable-json-parse-with-source"));
+#else
+  if (op.getBoolOption("enable-json-parse-with-source")) {
+    fprintf(stderr, "JSON.parse with source is not enabled on this build.\n");
+  }
+#endif
 
   if (op.getBoolOption("disable-weak-refs")) {
     JS::Prefs::setAtStartup_weakrefs(false);
@@ -12649,13 +12650,6 @@ bool SetContextOptions(JSContext* cx, const OptionParser& op) {
   enableAsyncStackCaptureDebuggeeOnly =
       op.getBoolOption("async-stacks-capture-debuggee-only");
   enableToSource = !op.getBoolOption("disable-tosource");
-#ifdef ENABLE_JSON_PARSE_WITH_SOURCE
-  enableJSONParseWithSource = op.getBoolOption("enable-json-parse-with-source");
-#else
-  if (op.getBoolOption("enable-json-parse-with-source")) {
-    fprintf(stderr, "JSON.parse with source is not enabled on this build.\n");
-  }
-#endif
   enableImportAttributesAssertSyntax =
       op.getBoolOption("enable-import-assertions");
   enableImportAttributes = op.getBoolOption("enable-import-attributes") ||

js/src/shell/jsshell.h

@@ -127,9 +127,6 @@ extern bool enableWellFormedUnicodeStrings;
 extern bool enableArrayBufferTransfer;
 extern bool enableArrayBufferResizable;
 extern bool enableSymbolsAsWeakMapKeys;
-#ifdef ENABLE_JSON_PARSE_WITH_SOURCE
-extern bool enableJSONParseWithSource;
-#endif
 extern bool enableNewSetMethods;
 extern bool enableImportAttributes;
 extern bool enableImportAttributesAssertSyntax;

js/src/vm/JSObject.cpp

@@ -2260,7 +2260,7 @@ JS_PUBLIC_API bool js::ShouldIgnorePropertyDefinition(JSContext* cx,
 
 #ifdef ENABLE_JSON_PARSE_WITH_SOURCE
   if (key == JSProto_JSON &&
-      !cx->realm()->creationOptions().getJSONParseWithSource() &&
+      !JS::Prefs::experimental_json_parse_with_source() &&
       (id == NameToId(cx->names().isRawJSON) ||
        id == NameToId(cx->names().rawJSON))) {
     return true;

modules/libpref/init/StaticPrefList.yaml

@@ -7663,6 +7663,14 @@
     mirror: always
 #endif  // NIGHTLY_BUILD
 
+#ifdef ENABLE_JSON_PARSE_WITH_SOURCE
+-   name: javascript.options.experimental.json_parse_with_source
+    type: bool
+    value: false
+    mirror: always
+    set_spidermonkey_pref: startup
+#endif  // ENABLE_JSON_PARSE_WITH_SOURCE
+
 - name: javascript.options.wasm_caching
   type: bool
   value: true