js/src/jsapi.cpp
author Jeff Walden <jwalden@mit.edu>
Thu, 08 Nov 2018 18:42:48 -0800
changeset 502944 56eaf6c976d377cba4e44a302bdeda9e7420bd94
parent 500631 e6ae3beb07bb883a96bb101ed720f1e5b4d998ff
child 503047 0dc9d562a03afd2836c517b44bb80ae5526186f1
permissions -rw-r--r--
Bug 1485800 - Rename SourceBufferHolder to SourceText, and add a <typename Unit> template parameter to it so it can hold putative UTF-8 or UTF-16 source text. r=tcampbell, r=fitzgen

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 * vim: set ts=8 sts=4 et sw=4 tw=99:
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/*
 * JavaScript API.
 */

#include "jsapi.h"

#include "mozilla/FloatingPoint.h"
#include "mozilla/Maybe.h"
#include "mozilla/PodOperations.h"
#include "mozilla/Sprintf.h"

#include <ctype.h>
#ifdef __linux__
# include <dlfcn.h>
#endif
#include <stdarg.h>
#include <string.h>

#include "jsdate.h"
#include "jsexn.h"
#include "jsfriendapi.h"
#include "jsmath.h"
#include "jsnum.h"
#include "jstypes.h"
#include "jsutil.h"

#include "builtin/Array.h"
#include "builtin/AtomicsObject.h"
#include "builtin/Boolean.h"
#include "builtin/Eval.h"
#include "builtin/JSON.h"
#include "builtin/MapObject.h"
#include "builtin/Promise.h"
#include "builtin/RegExp.h"
#include "builtin/Stream.h"
#include "builtin/String.h"
#include "builtin/Symbol.h"
#ifdef ENABLE_BINARYDATA
# include "builtin/TypedObject.h"
#endif
#include "frontend/BytecodeCompiler.h"
#include "gc/FreeOp.h"
#include "gc/Marking.h"
#include "gc/Policy.h"
#include "gc/PublicIterators.h"
#include "gc/WeakMap.h"
#include "jit/JitCommon.h"
#include "jit/JitSpewer.h"
#include "js/CharacterEncoding.h"
#include "js/CompilationAndEvaluation.h"
#include "js/CompileOptions.h"
#include "js/Conversions.h"
#include "js/Date.h"
#include "js/Initialization.h"
#include "js/JSON.h"
#include "js/LocaleSensitive.h"
#include "js/Proxy.h"
#include "js/SliceBudget.h"
#include "js/SourceText.h"
#include "js/StableStringChars.h"
#include "js/StructuredClone.h"
#include "js/Utility.h"
#include "js/Wrapper.h"
#include "util/CompleteFile.h"
#include "util/StringBuffer.h"
#include "util/Text.h"
#include "vm/AsyncFunction.h"
#include "vm/AsyncIteration.h"
#include "vm/DateObject.h"
#include "vm/Debugger.h"
#include "vm/EnvironmentObject.h"
#include "vm/ErrorObject.h"
#include "vm/HelperThreads.h"
#include "vm/Interpreter.h"
#include "vm/Iteration.h"
#include "vm/JSAtom.h"
#include "vm/JSContext.h"
#include "vm/JSFunction.h"
#include "vm/JSObject.h"
#include "vm/JSScript.h"
#include "vm/RegExpStatics.h"
#include "vm/Runtime.h"
#include "vm/SavedStacks.h"
#include "vm/SelfHosting.h"
#include "vm/Shape.h"
#include "vm/StringType.h"
#include "vm/SymbolType.h"
#include "vm/WrapperObject.h"
#include "vm/Xdr.h"
#include "wasm/AsmJS.h"
#include "wasm/WasmModule.h"

#include "vm/Compartment-inl.h"
#include "vm/Interpreter-inl.h"
#include "vm/JSAtom-inl.h"
#include "vm/JSFunction-inl.h"
#include "vm/JSScript-inl.h"
#include "vm/NativeObject-inl.h"
#include "vm/SavedStacks-inl.h"
#include "vm/StringType-inl.h"

using namespace js;

using mozilla::Maybe;
using mozilla::PodCopy;
using mozilla::Some;

using JS::AutoStableStringChars;
using JS::CompileOptions;
using JS::ReadOnlyCompileOptions;
using JS::SourceText;

#ifdef HAVE_VA_LIST_AS_ARRAY
#define JS_ADDRESSOF_VA_LIST(ap) ((va_list*)(ap))
#else
#define JS_ADDRESSOF_VA_LIST(ap) (&(ap))
#endif

JS_PUBLIC_API(bool)
JS::CallArgs::requireAtLeast(JSContext* cx, const char* fnname, unsigned required) const
{
    if (length() < required) {
        char numArgsStr[40];
        SprintfLiteral(numArgsStr, "%u", required - 1);
        JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_MORE_ARGS_NEEDED,
                                  fnname, numArgsStr, required == 2 ? "" : "s");
        return false;
    }

    return true;
}

static bool
ErrorTakesArguments(unsigned msg)
{
    MOZ_ASSERT(msg < JSErr_Limit);
    unsigned argCount = js_ErrorFormatString[msg].argCount;
    MOZ_ASSERT(argCount <= 2);
    return argCount == 1 || argCount == 2;
}

static bool
ErrorTakesObjectArgument(unsigned msg)
{
    MOZ_ASSERT(msg < JSErr_Limit);
    unsigned argCount = js_ErrorFormatString[msg].argCount;
    MOZ_ASSERT(argCount <= 2);
    return argCount == 2;
}

JS_PUBLIC_API(bool)
JS::ObjectOpResult::reportStrictErrorOrWarning(JSContext* cx, HandleObject obj, HandleId id,
                                               bool strict)
{
    static_assert(unsigned(OkCode) == unsigned(JSMSG_NOT_AN_ERROR),
                  "unsigned value of OkCode must not be an error code");
    MOZ_ASSERT(code_ != Uninitialized);
    MOZ_ASSERT(!ok());
    cx->check(obj);

    unsigned flags = strict ? JSREPORT_ERROR : (JSREPORT_WARNING | JSREPORT_STRICT);
    if (code_ == JSMSG_OBJECT_NOT_EXTENSIBLE) {
        RootedValue val(cx, ObjectValue(*obj));
        return ReportValueErrorFlags(cx, flags, code_, JSDVG_IGNORE_STACK, val,
                                     nullptr, nullptr, nullptr);
    }

    if (ErrorTakesArguments(code_)) {
        UniqueChars propName = IdToPrintableUTF8(cx, id, IdToPrintableBehavior::IdIsPropertyKey);
        if (!propName) {
            return false;
        }

        if (code_ == JSMSG_SET_NON_OBJECT_RECEIVER) {
            // We know that the original receiver was a primitive, so unbox it.
            RootedValue val(cx, ObjectValue(*obj));
            if (!obj->is<ProxyObject>()) {
                if (!Unbox(cx, obj, &val)) {
                    return false;
                }
            }
            return ReportValueErrorFlags(cx, flags, code_, JSDVG_IGNORE_STACK, val,
                                         nullptr, propName.get(), nullptr);
        }

        if (ErrorTakesObjectArgument(code_)) {
            return JS_ReportErrorFlagsAndNumberUTF8(cx, flags, GetErrorMessage, nullptr, code_,
                                                    obj->getClass()->name, propName.get());
        }

        return JS_ReportErrorFlagsAndNumberUTF8(cx, flags, GetErrorMessage, nullptr, code_,
                                                propName.get());
    }
    return JS_ReportErrorFlagsAndNumberASCII(cx, flags, GetErrorMessage, nullptr, code_);
}

JS_PUBLIC_API(bool)
JS::ObjectOpResult::reportStrictErrorOrWarning(JSContext* cx, HandleObject obj, bool strict)
{
    MOZ_ASSERT(code_ != Uninitialized);
    MOZ_ASSERT(!ok());
    MOZ_ASSERT(!ErrorTakesArguments(code_));
    cx->check(obj);

    unsigned flags = strict ? JSREPORT_ERROR : (JSREPORT_WARNING | JSREPORT_STRICT);
    return JS_ReportErrorFlagsAndNumberASCII(cx, flags, GetErrorMessage, nullptr, code_);
}

JS_PUBLIC_API(bool)
JS::ObjectOpResult::failCantRedefineProp()
{
    return fail(JSMSG_CANT_REDEFINE_PROP);
}

JS_PUBLIC_API(bool)
JS::ObjectOpResult::failReadOnly()
{
    return fail(JSMSG_READ_ONLY);
}

JS_PUBLIC_API(bool)
JS::ObjectOpResult::failGetterOnly()
{
    return fail(JSMSG_GETTER_ONLY);
}

JS_PUBLIC_API(bool)
JS::ObjectOpResult::failCantDelete()
{
    return fail(JSMSG_CANT_DELETE);
}

JS_PUBLIC_API(bool)
JS::ObjectOpResult::failCantSetInterposed()
{
    return fail(JSMSG_CANT_SET_INTERPOSED);
}

JS_PUBLIC_API(bool)
JS::ObjectOpResult::failCantDefineWindowElement()
{
    return fail(JSMSG_CANT_DEFINE_WINDOW_ELEMENT);
}

JS_PUBLIC_API(bool)
JS::ObjectOpResult::failCantDeleteWindowElement()
{
    return fail(JSMSG_CANT_DELETE_WINDOW_ELEMENT);
}

JS_PUBLIC_API(bool)
JS::ObjectOpResult::failCantDeleteWindowNamedProperty()
{
    return fail(JSMSG_CANT_DELETE_WINDOW_NAMED_PROPERTY);
}

JS_PUBLIC_API(bool)
JS::ObjectOpResult::failCantPreventExtensions()
{
    return fail(JSMSG_CANT_PREVENT_EXTENSIONS);
}

JS_PUBLIC_API(bool)
JS::ObjectOpResult::failCantSetProto()
{
    return fail(JSMSG_CANT_SET_PROTO);
}

JS_PUBLIC_API(bool)
JS::ObjectOpResult::failNoNamedSetter()
{
    return fail(JSMSG_NO_NAMED_SETTER);
}

JS_PUBLIC_API(bool)
JS::ObjectOpResult::failNoIndexedSetter()
{
    return fail(JSMSG_NO_INDEXED_SETTER);
}

JS_PUBLIC_API(bool)
JS::ObjectOpResult::failNotDataDescriptor()
{
    return fail(JSMSG_NOT_DATA_DESCRIPTOR);
}

JS_PUBLIC_API(int64_t)
JS_Now()
{
    return PRMJ_Now();
}

JS_PUBLIC_API(Value)
JS_GetNaNValue(JSContext* cx)
{
    return cx->runtime()->NaNValue;
}

JS_PUBLIC_API(Value)
JS_GetNegativeInfinityValue(JSContext* cx)
{
    return cx->runtime()->negativeInfinityValue;
}

JS_PUBLIC_API(Value)
JS_GetPositiveInfinityValue(JSContext* cx)
{
    return cx->runtime()->positiveInfinityValue;
}

JS_PUBLIC_API(Value)
JS_GetEmptyStringValue(JSContext* cx)
{
    return StringValue(cx->runtime()->emptyString);
}

JS_PUBLIC_API(JSString*)
JS_GetEmptyString(JSContext* cx)
{
    MOZ_ASSERT(cx->emptyString());
    return cx->emptyString();
}

namespace js {

void
AssertHeapIsIdle()
{
    MOZ_ASSERT(!JS::RuntimeHeapIsBusy());
}

} // namespace js

static void
AssertHeapIsIdleOrIterating()
{
    MOZ_ASSERT(!JS::RuntimeHeapIsCollecting());
}

static void
AssertHeapIsIdleOrStringIsFlat(JSString* str)
{
    /*
     * We allow some functions to be called during a GC as long as the argument
     * is a flat string, since that will not cause allocation.
     */
    MOZ_ASSERT_IF(JS::RuntimeHeapIsBusy(), str->isFlat());
}

JS_PUBLIC_API(bool)
JS_ValueToObject(JSContext* cx, HandleValue value, MutableHandleObject objp)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(value);
    if (value.isNullOrUndefined()) {
        objp.set(nullptr);
        return true;
    }
    JSObject* obj = ToObject(cx, value);
    if (!obj) {
        return false;
    }
    objp.set(obj);
    return true;
}

JS_PUBLIC_API(JSFunction*)
JS_ValueToFunction(JSContext* cx, HandleValue value)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(value);
    return ReportIfNotFunction(cx, value);
}

JS_PUBLIC_API(JSFunction*)
JS_ValueToConstructor(JSContext* cx, HandleValue value)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(value);
    return ReportIfNotFunction(cx, value);
}

JS_PUBLIC_API(JSString*)
JS_ValueToSource(JSContext* cx, HandleValue value)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(value);
    return ValueToSource(cx, value);
}

JS_PUBLIC_API(bool)
JS_DoubleIsInt32(double d, int32_t* ip)
{
    return mozilla::NumberIsInt32(d, ip);
}

JS_PUBLIC_API(JSType)
JS_TypeOfValue(JSContext* cx, HandleValue value)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(value);
    return TypeOfValue(value);
}

JS_PUBLIC_API(bool)
JS_StrictlyEqual(JSContext* cx, HandleValue value1, HandleValue value2, bool* equal)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(value1, value2);
    MOZ_ASSERT(equal);
    return StrictlyEqual(cx, value1, value2, equal);
}

JS_PUBLIC_API(bool)
JS_LooselyEqual(JSContext* cx, HandleValue value1, HandleValue value2, bool* equal)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(value1, value2);
    MOZ_ASSERT(equal);
    return LooselyEqual(cx, value1, value2, equal);
}

JS_PUBLIC_API(bool)
JS_SameValue(JSContext* cx, HandleValue value1, HandleValue value2, bool* same)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(value1, value2);
    MOZ_ASSERT(same);
    return SameValue(cx, value1, value2, same);
}

JS_PUBLIC_API(bool)
JS_IsBuiltinEvalFunction(JSFunction* fun)
{
    return IsAnyBuiltinEval(fun);
}

JS_PUBLIC_API(bool)
JS_IsBuiltinFunctionConstructor(JSFunction* fun)
{
    return fun->isBuiltinFunctionConstructor();
}

JS_PUBLIC_API(bool)
JS_IsFunctionBound(JSFunction* fun)
{
    return fun->isBoundFunction();
}

JS_PUBLIC_API(JSObject*)
JS_GetBoundFunctionTarget(JSFunction* fun)
{
    return fun->isBoundFunction() ?
               fun->getBoundFunctionTarget() : nullptr;
}

/************************************************************************/

JS_PUBLIC_API(JSContext*)
JS_NewContext(uint32_t maxbytes, uint32_t maxNurseryBytes, JSRuntime* parentRuntime)
{
    MOZ_ASSERT(JS::detail::libraryInitState == JS::detail::InitState::Running,
               "must call JS_Init prior to creating any JSContexts");

    // Make sure that all parent runtimes are the topmost parent.
    while (parentRuntime && parentRuntime->parentRuntime) {
        parentRuntime = parentRuntime->parentRuntime;
    }

    return NewContext(maxbytes, maxNurseryBytes, parentRuntime);
}

JS_PUBLIC_API(JSContext*)
JS_NewCooperativeContext(JSContext* siblingContext)
{
    MOZ_CRASH("Cooperative scheduling is unsupported");
}

JS_PUBLIC_API(void)
JS_YieldCooperativeContext(JSContext* cx)
{
    MOZ_CRASH("Cooperative scheduling is unsupported");
}

JS_PUBLIC_API(void)
JS_ResumeCooperativeContext(JSContext* cx)
{
    MOZ_CRASH("Cooperative scheduling is unsupported");
}

JS_PUBLIC_API(void)
JS_DestroyContext(JSContext* cx)
{
    DestroyContext(cx);
}

JS_PUBLIC_API(void*)
JS_GetContextPrivate(JSContext* cx)
{
    return cx->data;
}

JS_PUBLIC_API(void)
JS_SetContextPrivate(JSContext* cx, void* data)
{
    cx->data = data;
}

JS_PUBLIC_API(void)
JS_SetFutexCanWait(JSContext* cx)
{
    cx->fx.setCanWait(true);
}

JS_PUBLIC_API(JSRuntime*)
JS_GetParentRuntime(JSContext* cx)
{
    return cx->runtime()->parentRuntime ? cx->runtime()->parentRuntime : cx->runtime();
}

JS_PUBLIC_API(JSRuntime*)
JS_GetRuntime(JSContext* cx)
{
    return cx->runtime();
}

JS_PUBLIC_API(JS::ContextOptions&)
JS::ContextOptionsRef(JSContext* cx)
{
    return cx->options();
}

JS_PUBLIC_API(bool)
JS::InitSelfHostedCode(JSContext* cx)
{
    MOZ_RELEASE_ASSERT(!cx->runtime()->hasInitializedSelfHosting(),
                       "JS::InitSelfHostedCode() called more than once");

    AutoNoteSingleThreadedRegion anstr;

    JSRuntime* rt = cx->runtime();

    if (!rt->initializeAtoms(cx)) {
        return false;
    }

#ifndef JS_CODEGEN_NONE
    if (!rt->getJitRuntime(cx)) {
        return false;
    }
#endif

    if (!rt->initSelfHosting(cx)) {
        return false;
    }

    if (!rt->parentRuntime && !rt->initMainAtomsTables(cx)) {
        return false;
    }

    return true;
}

JS_PUBLIC_API(const char*)
JS_GetImplementationVersion(void)
{
    return "JavaScript-C" MOZILLA_VERSION;
}

JS_PUBLIC_API(void)
JS_SetDestroyCompartmentCallback(JSContext* cx, JSDestroyCompartmentCallback callback)
{
    cx->runtime()->destroyCompartmentCallback = callback;
}

JS_PUBLIC_API(void)
JS_SetSizeOfIncludingThisCompartmentCallback(JSContext* cx,
                                             JSSizeOfIncludingThisCompartmentCallback callback)
{
    cx->runtime()->sizeOfIncludingThisCompartmentCallback = callback;
}

#if defined(NIGHTLY_BUILD)
JS_PUBLIC_API(void)
JS_SetErrorInterceptorCallback(JSRuntime* rt, JSErrorInterceptor* callback)
{
    rt->errorInterception.interceptor = callback;
}

JS_PUBLIC_API(JSErrorInterceptor*)
JS_GetErrorInterceptorCallback(JSRuntime* rt)
{
    return rt->errorInterception.interceptor;
}

JS_PUBLIC_API(Maybe<JSExnType>)
JS_GetErrorType(const JS::Value& val)
{
    // All errors are objects.
    if (!val.isObject()) {
        return mozilla::Nothing();
    }

    const JSObject& obj = val.toObject();

    // All errors are `ErrorObject`.
    if (!obj.is<js::ErrorObject>()) {
        // Not one of the primitive errors.
        return mozilla::Nothing();
    }

    const js::ErrorObject& err = obj.as<js::ErrorObject>();
    return mozilla::Some(err.type());
}

#endif // defined(NIGHTLY_BUILD)

JS_PUBLIC_API(void)
JS_SetWrapObjectCallbacks(JSContext* cx, const JSWrapObjectCallbacks* callbacks)
{
    cx->runtime()->wrapObjectCallbacks = callbacks;
}

JS_PUBLIC_API(void)
JS_SetExternalStringSizeofCallback(JSContext* cx, JSExternalStringSizeofCallback callback)
{
    cx->runtime()->externalStringSizeofCallback = callback;
}

JS_PUBLIC_API(Realm*)
JS::EnterRealm(JSContext* cx, JSObject* target)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);

    MOZ_DIAGNOSTIC_ASSERT(!js::IsCrossCompartmentWrapper(target));

    Realm* oldRealm = cx->realm();
    cx->enterRealmOf(target);
    return oldRealm;
}

JS_PUBLIC_API(void)
JS::LeaveRealm(JSContext* cx, JS::Realm* oldRealm)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->leaveRealm(oldRealm);
}

JSAutoRealm::JSAutoRealm(JSContext* cx, JSObject* target
                         MOZ_GUARD_OBJECT_NOTIFIER_PARAM_IN_IMPL)
  : cx_(cx),
    oldRealm_(cx->realm())
{
    MOZ_GUARD_OBJECT_NOTIFIER_INIT;
    MOZ_DIAGNOSTIC_ASSERT(!js::IsCrossCompartmentWrapper(target));
    AssertHeapIsIdleOrIterating();
    cx_->enterRealmOf(target);
}

JSAutoRealm::JSAutoRealm(JSContext* cx, JSScript* target
                         MOZ_GUARD_OBJECT_NOTIFIER_PARAM_IN_IMPL)
  : cx_(cx),
    oldRealm_(cx->realm())
{
    MOZ_GUARD_OBJECT_NOTIFIER_INIT;
    AssertHeapIsIdleOrIterating();
    cx_->enterRealmOf(target);
}

JSAutoRealm::~JSAutoRealm()
{
    cx_->leaveRealm(oldRealm_);
}

JSAutoNullableRealm::JSAutoNullableRealm(JSContext* cx,
                                         JSObject* targetOrNull
                                         MOZ_GUARD_OBJECT_NOTIFIER_PARAM_IN_IMPL)
  : cx_(cx),
    oldRealm_(cx->realm())
{
    MOZ_GUARD_OBJECT_NOTIFIER_INIT;
    AssertHeapIsIdleOrIterating();
    if (targetOrNull) {
        MOZ_DIAGNOSTIC_ASSERT(!js::IsCrossCompartmentWrapper(targetOrNull));
        cx_->enterRealmOf(targetOrNull);
    } else {
        cx_->enterNullRealm();
    }
}

JSAutoNullableRealm::~JSAutoNullableRealm()
{
    cx_->leaveRealm(oldRealm_);
}

JS_PUBLIC_API(void)
JS_SetCompartmentPrivate(JS::Compartment* compartment, void* data)
{
    compartment->data = data;
}

JS_PUBLIC_API(void*)
JS_GetCompartmentPrivate(JS::Compartment* compartment)
{
    return compartment->data;
}

JS_PUBLIC_API(void)
JS_MarkCrossZoneId(JSContext* cx, jsid id)
{
    cx->markId(id);
}

JS_PUBLIC_API(void)
JS_MarkCrossZoneIdValue(JSContext* cx, const Value& value)
{
    cx->markAtomValue(value);
}

JS_PUBLIC_API(void)
JS_SetZoneUserData(JS::Zone* zone, void* data)
{
    zone->data = data;
}

JS_PUBLIC_API(void*)
JS_GetZoneUserData(JS::Zone* zone)
{
    return zone->data;
}

JS_PUBLIC_API(bool)
JS_WrapObject(JSContext* cx, MutableHandleObject objp)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    if (objp) {
        JS::ExposeObjectToActiveJS(objp);
    }
    return cx->compartment()->wrap(cx, objp);
}

JS_PUBLIC_API(bool)
JS_WrapValue(JSContext* cx, MutableHandleValue vp)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    JS::ExposeValueToActiveJS(vp);
    return cx->compartment()->wrap(cx, vp);
}

static void
ReleaseAssertObjectHasNoWrappers(JSContext* cx, HandleObject target)
{
    RootedValue origv(cx, ObjectValue(*target));

    for (CompartmentsIter c(cx->runtime()); !c.done(); c.next()) {
        if (c->lookupWrapper(origv)) {
            MOZ_CRASH("wrapper found for target object");
        }
    }
}

/*
 * [SMDOC] Brain transplants.
 *
 * Not for beginners or the squeamish.
 *
 * Sometimes a web spec requires us to transplant an object from one
 * compartment to another, like when a DOM node is inserted into a document in
 * another window and thus gets "adopted". We cannot literally change the
 * `.compartment()` of a `JSObject`; that would break the compartment
 * invariants. However, as usual, we have a workaround using wrappers.
 *
 * Of all the wrapper-based workarounds we do, it's safe to say this is the
 * most spectacular and questionable.
 *
 * `JS_TransplantObject(cx, origobj, target)` changes `origobj` into a
 * simulacrum of `target`, using highly esoteric means. To JS code, the effect
 * is as if `origobj` magically "became" `target`, but most often what actually
 * happens is that `origobj` gets turned into a cross-compartment wrapper for
 * `target`. The old behavior and contents of `origobj` are overwritten or
 * discarded.
 *
 * Thus, to "transplant" an object from one compartment to another:
 *
 * 1.  Let `origobj` be the object that you want to move. First, create a
 *     clone of it, `target`, in the destination compartment.
 *
 *     In our DOM adoption example, `target` will be a Node of the same type as
 *     `origobj`, same content, but in the adopting document.  We're not done
 *     yet: the spec for DOM adoption requires that `origobj.ownerDocument`
 *     actually change. All we've done so far is make a copy.
 *
 * 2.  Call `JS_TransplantObject(cx, origobj, target)`. This typically turns
 *     `origobj` into a wrapper for `target`, so that any JS code that has a
 *     reference to `origobj` will observe it to have the behavior of `target`
 *     going forward. In addition, all existing wrappers for `origobj` are
 *     changed into wrappers for `target`, extending the illusion to those
 *     compartments as well.
 *
 * During navigation, we use the above technique to transplant the WindowProxy
 * into the new Window's compartment.
 *
 * A few rules:
 *
 * -   `origobj` and `target` must be two distinct objects of the same `JSClass`.
 *     Some classes may not support transplantation; WindowProxy objects and DOM
 *     nodes are OK.
 *
 * -   `target` should be created specifically to be passed to this function.
 *     There must be no existing cross-compartment wrappers for it; ideally
 *     there shouldn't be any pointers to it at all, except the one passed in.
 *
 * -   `target` shouldn't be used afterwards. Instead, `JS_TransplantObject`
 *     returns a pointer to the transplanted object, which might be `target`
 *     but might be some other object in the same compartment. Use that.
 *
 * The reason for this last rule is that JS_TransplantObject does very strange
 * things in some cases, like swapping `target`'s brain with that of another
 * object. Leaving `target` behaving like its former self is not a goal.
 *
 * We don't have a good way to recover from failure in this function, so
 * we intentionally crash instead.
 */

JS_PUBLIC_API(JSObject*)
JS_TransplantObject(JSContext* cx, HandleObject origobj, HandleObject target)
{
    AssertHeapIsIdle();
    MOZ_ASSERT(origobj != target);
    MOZ_ASSERT(!origobj->is<CrossCompartmentWrapperObject>());
    MOZ_ASSERT(!target->is<CrossCompartmentWrapperObject>());
    MOZ_ASSERT(origobj->getClass() == target->getClass());
    ReleaseAssertObjectHasNoWrappers(cx, target);
    MOZ_ASSERT(JS::CellIsNotGray(target));

    RootedValue origv(cx, ObjectValue(*origobj));
    RootedObject newIdentity(cx);

    // Don't allow a compacting GC to observe any intermediate state.
    AutoDisableCompactingGC nocgc(cx);

    AutoDisableProxyCheck adpc;

    JS::Compartment* destination = target->compartment();

    if (origobj->compartment() == destination) {
        // If the original object is in the same compartment as the
        // destination, then we know that we won't find a wrapper in the
        // destination's cross compartment map and that the same
        // object will continue to work.
        AutoRealmUnchecked ar(cx, origobj->nonCCWRealm());
        JSObject::swap(cx, origobj, target);
        newIdentity = origobj;
    } else if (WrapperMap::Ptr p = destination->lookupWrapper(origv)) {
        // There might already be a wrapper for the original object in
        // the new compartment. If there is, we use its identity and swap
        // in the contents of |target|.
        newIdentity = &p->value().get().toObject();

        // When we remove origv from the wrapper map, its wrapper, newIdentity,
        // must immediately cease to be a cross-compartment wrapper. Nuke it.
        destination->removeWrapper(p);
        NukeCrossCompartmentWrapper(cx, newIdentity);

        AutoRealm ar(cx, newIdentity);
        JSObject::swap(cx, newIdentity, target);
    } else {
        // Otherwise, we use |target| for the new identity object.
        newIdentity = target;
    }

    // Now, iterate through other scopes looking for references to the old
    // object, and update the relevant cross-compartment wrappers. We do this
    // even if origobj is in the same compartment as target and thus
    // `newIdentity == origobj`, because this process also clears out any
    // cached wrapper state.
    if (!RemapAllWrappersForObject(cx, origobj, newIdentity)) {
        MOZ_CRASH();
    }

    // Lastly, update the original object to point to the new one.
    if (origobj->compartment() != destination) {
        RootedObject newIdentityWrapper(cx, newIdentity);
        AutoRealmUnchecked ar(cx, origobj->nonCCWRealm());
        if (!JS_WrapObject(cx, &newIdentityWrapper)) {
            MOZ_CRASH();
        }
        MOZ_ASSERT(Wrapper::wrappedObject(newIdentityWrapper) == newIdentity);
        JSObject::swap(cx, origobj, newIdentityWrapper);
        if (!origobj->compartment()->putWrapper(cx, CrossCompartmentKey(newIdentity), origv)) {
            MOZ_CRASH();
        }
    }

    // The new identity object might be one of several things. Return it to avoid
    // ambiguity.
    MOZ_ASSERT(JS::CellIsNotGray(newIdentity));
    return newIdentity;
}

/*
 * Recompute all cross-compartment wrappers for an object, resetting state.
 * Gecko uses this to clear Xray wrappers when doing a navigation that reuses
 * the inner window and global object.
 */
JS_PUBLIC_API(bool)
JS_RefreshCrossCompartmentWrappers(JSContext* cx, HandleObject obj)
{
    return RemapAllWrappersForObject(cx, obj, obj);
}

typedef struct JSStdName {
    size_t      atomOffset;     /* offset of atom pointer in JSAtomState */
    JSProtoKey  key;
    bool isDummy() const { return key == JSProto_Null; }
    bool isSentinel() const { return key == JSProto_LIMIT; }
} JSStdName;

static const JSStdName*
LookupStdName(const JSAtomState& names, JSAtom* name, const JSStdName* table)
{
    for (unsigned i = 0; !table[i].isSentinel(); i++) {
        if (table[i].isDummy()) {
            continue;
        }
        JSAtom* atom = AtomStateOffsetToName(names, table[i].atomOffset);
        MOZ_ASSERT(atom);
        if (name == atom) {
            return &table[i];
        }
    }

    return nullptr;
}

/*
 * Table of standard classes, indexed by JSProtoKey. For entries where the
 * JSProtoKey does not correspond to a class with a meaningful constructor, we
 * insert a null entry into the table.
 */
#define STD_NAME_ENTRY(name, init, clasp) { NAME_OFFSET(name), JSProto_##name },
#define STD_DUMMY_ENTRY(name, init, dummy) { 0, JSProto_Null },
static const JSStdName standard_class_names[] = {
  JS_FOR_PROTOTYPES(STD_NAME_ENTRY, STD_DUMMY_ENTRY)
  { 0, JSProto_LIMIT }
};

/*
 * Table of top-level function and constant names and the JSProtoKey of the
 * standard class that initializes them.
 */
static const JSStdName builtin_property_names[] = {
    { NAME_OFFSET(eval), JSProto_Object },

    /* Global properties and functions defined by the Number class. */
    { NAME_OFFSET(NaN), JSProto_Number },
    { NAME_OFFSET(Infinity), JSProto_Number },
    { NAME_OFFSET(isNaN), JSProto_Number },
    { NAME_OFFSET(isFinite), JSProto_Number },
    { NAME_OFFSET(parseFloat), JSProto_Number },
    { NAME_OFFSET(parseInt), JSProto_Number },

    /* String global functions. */
    { NAME_OFFSET(escape), JSProto_String },
    { NAME_OFFSET(unescape), JSProto_String },
    { NAME_OFFSET(decodeURI), JSProto_String },
    { NAME_OFFSET(encodeURI), JSProto_String },
    { NAME_OFFSET(decodeURIComponent), JSProto_String },
    { NAME_OFFSET(encodeURIComponent), JSProto_String },
    { NAME_OFFSET(uneval), JSProto_String },

    { 0, JSProto_LIMIT }
};

JS_PUBLIC_API(bool)
JS_ResolveStandardClass(JSContext* cx, HandleObject obj, HandleId id, bool* resolved)
{
    const JSStdName* stdnm;

    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj, id);

    Handle<GlobalObject*> global = obj.as<GlobalObject>();
    *resolved = false;

    if (!JSID_IS_ATOM(id)) {
        return true;
    }

    /* Check whether we're resolving 'undefined', and define it if so. */
    JSAtom* idAtom = JSID_TO_ATOM(id);
    JSAtom* undefinedAtom = cx->names().undefined;
    if (idAtom == undefinedAtom) {
        *resolved = true;
        return DefineDataProperty(cx, global, id, UndefinedHandleValue,
                                  JSPROP_PERMANENT | JSPROP_READONLY | JSPROP_RESOLVING);
    }

    /* Try for class constructors/prototypes named by well-known atoms. */
    stdnm = LookupStdName(cx->names(), idAtom, standard_class_names);

    /* Try less frequently used top-level functions and constants. */
    if (!stdnm) {
        stdnm = LookupStdName(cx->names(), idAtom, builtin_property_names);
    }

    if (stdnm && GlobalObject::skipDeselectedConstructor(cx, stdnm->key)) {
        stdnm = nullptr;
    }

    // If this class is anonymous, then it doesn't exist as a global
    // property, so we won't resolve anything.
    JSProtoKey key = stdnm ? stdnm->key : JSProto_Null;
    if (key != JSProto_Null) {
        const Class* clasp = ProtoKeyToClass(key);
        if (!clasp || !(clasp->flags & JSCLASS_IS_ANONYMOUS)) {
            if (!GlobalObject::ensureConstructor(cx, global, key)) {
                return false;
            }

            *resolved = true;
            return true;
        }
    }

    // There is no such property to resolve. An ordinary resolve hook would
    // just return true at this point. But the global object is special in one
    // more way: its prototype chain is lazily initialized. That is,
    // global->getProto() might be null right now because we haven't created
    // Object.prototype yet. Force it now.
    return GlobalObject::getOrCreateObjectPrototype(cx, global);
}

JS_PUBLIC_API(bool)
JS_MayResolveStandardClass(const JSAtomState& names, jsid id, JSObject* maybeObj)
{
    MOZ_ASSERT_IF(maybeObj, maybeObj->is<GlobalObject>());

    // The global object's resolve hook is special: JS_ResolveStandardClass
    // initializes the prototype chain lazily. Only attempt to optimize here
    // if we know the prototype chain has been initialized.
    if (!maybeObj || !maybeObj->staticPrototype()) {
        return true;
    }

    if (!JSID_IS_ATOM(id)) {
        return false;
    }

    JSAtom* atom = JSID_TO_ATOM(id);

    // This will return true even for deselected constructors.  (To do
    // better, we need a JSContext here; it's fine as it is.)

    return atom == names.undefined ||
           LookupStdName(names, atom, standard_class_names) ||
           LookupStdName(names, atom, builtin_property_names);
}

JS_PUBLIC_API(bool)
JS_EnumerateStandardClasses(JSContext* cx, HandleObject obj)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj);
    Handle<GlobalObject*> global = obj.as<GlobalObject>();
    return GlobalObject::initStandardClasses(cx, global);
}

static bool
EnumerateStandardClassesInTable(JSContext* cx, Handle<GlobalObject*> global,
                                AutoIdVector& properties, const JSStdName* table,
                                bool includeResolved)
{
    for (unsigned i = 0; !table[i].isSentinel(); i++) {
        if (table[i].isDummy()) {
            continue;
        }

        JSProtoKey key = table[i].key;

        // If the standard class has been resolved, the properties have been
        // defined on the global so we don't need to add them here.
        if (!includeResolved && global->isStandardClassResolved(key)) {
            continue;
        }

        if (GlobalObject::skipDeselectedConstructor(cx, key)) {
            continue;
        }

        if (const Class* clasp = ProtoKeyToClass(key)) {
            if (clasp->flags & JSCLASS_IS_ANONYMOUS) {
                continue;
            }
            if (!clasp->specShouldDefineConstructor()) {
                continue;
            }
        }

        jsid id = NameToId(AtomStateOffsetToName(cx->names(), table[i].atomOffset));
        if (!properties.append(id)) {
            return false;
        }
    }

    return true;
}

static bool
EnumerateStandardClasses(JSContext* cx, JS::HandleObject obj, JS::AutoIdVector& properties,
                         bool enumerableOnly, bool includeResolved)
{
    if (enumerableOnly) {
        // There are no enumerable standard classes and "undefined" is
        // not enumerable.
        return true;
    }

    Handle<GlobalObject*> global = obj.as<GlobalObject>();

    // It's fine to always append |undefined| here, it's non-configurable and
    // the enumeration code filters duplicates.
    if (!properties.append(NameToId(cx->names().undefined))) {
        return false;
    }

    if (!EnumerateStandardClassesInTable(cx, global, properties, standard_class_names,
                                         includeResolved)) {
        return false;
    }
    if (!EnumerateStandardClassesInTable(cx, global, properties, builtin_property_names,
                                         includeResolved)) {
        return false;
    }

    return true;
}

JS_PUBLIC_API(bool)
JS_NewEnumerateStandardClasses(JSContext* cx, JS::HandleObject obj, JS::AutoIdVector& properties,
                               bool enumerableOnly)
{
    return EnumerateStandardClasses(cx, obj, properties, enumerableOnly, false);
}

JS_PUBLIC_API(bool)
JS_NewEnumerateStandardClassesIncludingResolved(JSContext* cx, JS::HandleObject obj,
                                                JS::AutoIdVector& properties,
                                                bool enumerableOnly)
{
    return EnumerateStandardClasses(cx, obj, properties, enumerableOnly, true);
}

JS_PUBLIC_API(bool)
JS_GetClassObject(JSContext* cx, JSProtoKey key, MutableHandleObject objp)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    JSObject* obj = GlobalObject::getOrCreateConstructor(cx, key);
    if (!obj) {
        return false;
    }
    objp.set(obj);
    return true;
}

JS_PUBLIC_API(bool)
JS_GetClassPrototype(JSContext* cx, JSProtoKey key, MutableHandleObject objp)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    JSObject* proto = GlobalObject::getOrCreatePrototype(cx, key);
    if (!proto) {
        return false;
    }
    objp.set(proto);
    return true;
}

namespace JS {

JS_PUBLIC_API(void)
ProtoKeyToId(JSContext* cx, JSProtoKey key, MutableHandleId idp)
{
    idp.set(NameToId(ClassName(key, cx)));
}

} /* namespace JS */

JS_PUBLIC_API(JSProtoKey)
JS_IdToProtoKey(JSContext* cx, HandleId id)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(id);

    if (!JSID_IS_ATOM(id)) {
        return JSProto_Null;
    }

    JSAtom* atom = JSID_TO_ATOM(id);
    const JSStdName* stdnm = LookupStdName(cx->names(), atom, standard_class_names);
    if (!stdnm) {
        return JSProto_Null;
    }

    if (GlobalObject::skipDeselectedConstructor(cx, stdnm->key)) {
        return JSProto_Null;
    }

    MOZ_ASSERT(MOZ_ARRAY_LENGTH(standard_class_names) == JSProto_LIMIT + 1);
    return static_cast<JSProtoKey>(stdnm - standard_class_names);
}

extern JS_PUBLIC_API(bool)
JS_IsGlobalObject(JSObject* obj)
{
    return obj->is<GlobalObject>();
}

extern JS_PUBLIC_API(JSObject*)
JS_GlobalLexicalEnvironment(JSObject* obj)
{
    return &obj->as<GlobalObject>().lexicalEnvironment();
}

extern JS_PUBLIC_API(bool)
JS_HasExtensibleLexicalEnvironment(JSObject* obj)
{
    return obj->is<GlobalObject>() || ObjectRealm::get(obj).getNonSyntacticLexicalEnvironment(obj);
}

extern JS_PUBLIC_API(JSObject*)
JS_ExtensibleLexicalEnvironment(JSObject* obj)
{
    JSObject* lexical = nullptr;
    if (obj->is<GlobalObject>()) {
        lexical = JS_GlobalLexicalEnvironment(obj);
    } else {
        lexical = ObjectRealm::get(obj).getNonSyntacticLexicalEnvironment(obj);
    }
    MOZ_ASSERT(lexical);
    return lexical;
}

JS_PUBLIC_API(JSObject*)
JS::CurrentGlobalOrNull(JSContext* cx)
{
    AssertHeapIsIdleOrIterating();
    CHECK_THREAD(cx);
    if (!cx->realm()) {
        return nullptr;
    }
    return cx->global();
}

JS_PUBLIC_API(JSObject*)
JS::GetNonCCWObjectGlobal(JSObject* obj)
{
    AssertHeapIsIdleOrIterating();
    MOZ_DIAGNOSTIC_ASSERT(!IsCrossCompartmentWrapper(obj));
    return &obj->nonCCWGlobal();
}

JS_PUBLIC_API(bool)
JS::detail::ComputeThis(JSContext* cx, Value* vp, MutableHandleObject thisObject)
{
    AssertHeapIsIdle();
    cx->check(vp[0], vp[1]);

    MutableHandleValue thisv = MutableHandleValue::fromMarkedLocation(&vp[1]);
    if (!BoxNonStrictThis(cx, thisv, thisv)) {
        return false;
    }

    thisObject.set(&thisv.toObject());
    return true;
}

static bool gProfileTimelineRecordingEnabled = false;

JS_PUBLIC_API(void)
JS::SetProfileTimelineRecordingEnabled(bool enabled)
{
    gProfileTimelineRecordingEnabled = enabled;
}

JS_PUBLIC_API(bool)
JS::IsProfileTimelineRecordingEnabled()
{
    return gProfileTimelineRecordingEnabled;
}

JS_PUBLIC_API(void*)
JS_malloc(JSContext* cx, size_t nbytes)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    return static_cast<void*>(cx->maybe_pod_malloc<uint8_t>(nbytes));
}

JS_PUBLIC_API(void*)
JS_realloc(JSContext* cx, void* p, size_t oldBytes, size_t newBytes)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    return static_cast<void*>(cx->maybe_pod_realloc<uint8_t>(static_cast<uint8_t*>(p),
                                                             oldBytes, newBytes));
}

JS_PUBLIC_API(void)
JS_free(JSContext* cx, void* p)
{
    return js_free(p);
}

JS_PUBLIC_API(void)
JS_freeop(JSFreeOp* fop, void* p)
{
    return FreeOp::get(fop)->free_(p);
}

JS_PUBLIC_API(void)
JS_updateMallocCounter(JSContext* cx, size_t nbytes)
{
    return cx->updateMallocCounter(nbytes);
}

#undef JS_AddRoot

JS_PUBLIC_API(bool)
JS_AddExtraGCRootsTracer(JSContext* cx, JSTraceDataOp traceOp, void* data)
{
    return cx->runtime()->gc.addBlackRootsTracer(traceOp, data);
}

JS_PUBLIC_API(void)
JS_RemoveExtraGCRootsTracer(JSContext* cx, JSTraceDataOp traceOp, void* data)
{
    return cx->runtime()->gc.removeBlackRootsTracer(traceOp, data);
}

JS_PUBLIC_API(bool)
JS::IsIdleGCTaskNeeded(JSRuntime* rt) {
  // Currently, we only collect nursery during idle time.
  return rt->gc.nursery().needIdleTimeCollection();
}

JS_PUBLIC_API(void)
JS::RunIdleTimeGCTask(JSRuntime* rt) {
  gc::GCRuntime& gc = rt->gc;
  if (gc.nursery().needIdleTimeCollection()) {
    gc.minorGC(JS::gcreason::IDLE_TIME_COLLECTION);
  }
}

JS_PUBLIC_API(void)
JS_GC(JSContext* cx)
{
    AssertHeapIsIdle();
    JS::PrepareForFullGC(cx);
    cx->runtime()->gc.gc(GC_NORMAL, JS::gcreason::API);
}

JS_PUBLIC_API(void)
JS_MaybeGC(JSContext* cx)
{
    gc::GCRuntime& gc = cx->runtime()->gc;
    gc.maybeGC(cx->zone());
}

JS_PUBLIC_API(void)
JS_SetGCCallback(JSContext* cx, JSGCCallback cb, void* data)
{
    AssertHeapIsIdle();
    cx->runtime()->gc.setGCCallback(cb, data);
}

JS_PUBLIC_API(void)
JS_SetObjectsTenuredCallback(JSContext* cx, JSObjectsTenuredCallback cb,
                             void* data)
{
    AssertHeapIsIdle();
    cx->runtime()->gc.setObjectsTenuredCallback(cb, data);
}

JS_PUBLIC_API(bool)
JS_AddFinalizeCallback(JSContext* cx, JSFinalizeCallback cb, void* data)
{
    AssertHeapIsIdle();
    return cx->runtime()->gc.addFinalizeCallback(cb, data);
}

JS_PUBLIC_API(void)
JS_RemoveFinalizeCallback(JSContext* cx, JSFinalizeCallback cb)
{
    cx->runtime()->gc.removeFinalizeCallback(cb);
}

JS_PUBLIC_API(bool)
JS_AddWeakPointerZonesCallback(JSContext* cx, JSWeakPointerZonesCallback cb, void* data)
{
    AssertHeapIsIdle();
    return cx->runtime()->gc.addWeakPointerZonesCallback(cb, data);
}

JS_PUBLIC_API(void)
JS_RemoveWeakPointerZonesCallback(JSContext* cx, JSWeakPointerZonesCallback cb)
{
    cx->runtime()->gc.removeWeakPointerZonesCallback(cb);
}

JS_PUBLIC_API(bool)
JS_AddWeakPointerCompartmentCallback(JSContext* cx, JSWeakPointerCompartmentCallback cb,
                                     void* data)
{
    AssertHeapIsIdle();
    return cx->runtime()->gc.addWeakPointerCompartmentCallback(cb, data);
}

JS_PUBLIC_API(void)
JS_RemoveWeakPointerCompartmentCallback(JSContext* cx, JSWeakPointerCompartmentCallback cb)
{
    cx->runtime()->gc.removeWeakPointerCompartmentCallback(cb);
}


JS_PUBLIC_API(void)
JS_UpdateWeakPointerAfterGC(JS::Heap<JSObject*>* objp)
{
    JS_UpdateWeakPointerAfterGCUnbarriered(objp->unsafeGet());
}

JS_PUBLIC_API(void)
JS_UpdateWeakPointerAfterGCUnbarriered(JSObject** objp)
{
    if (IsAboutToBeFinalizedUnbarriered(objp)) {
        *objp = nullptr;
    }
}

JS_PUBLIC_API(void)
JS_SetGCParameter(JSContext* cx, JSGCParamKey key, uint32_t value)
{
    cx->runtime()->gc.waitBackgroundSweepEnd();
    AutoLockGC lock(cx->runtime());
    MOZ_ALWAYS_TRUE(cx->runtime()->gc.setParameter(key, value, lock));
}

JS_PUBLIC_API(void)
JS_ResetGCParameter(JSContext* cx, JSGCParamKey key)
{
    cx->runtime()->gc.waitBackgroundSweepEnd();
    AutoLockGC lock(cx->runtime());
    cx->runtime()->gc.resetParameter(key, lock);
}

JS_PUBLIC_API(uint32_t)
JS_GetGCParameter(JSContext* cx, JSGCParamKey key)
{
    AutoLockGC lock(cx->runtime());
    return cx->runtime()->gc.getParameter(key, lock);
}

static const size_t NumGCConfigs = 14;
struct JSGCConfig {
    JSGCParamKey key;
    uint32_t value;
};

JS_PUBLIC_API(void)
JS_SetGCParametersBasedOnAvailableMemory(JSContext* cx, uint32_t availMem)
{
    static const JSGCConfig minimal[NumGCConfigs] = {
        {JSGC_MAX_MALLOC_BYTES, 6 * 1024 * 1024},
        {JSGC_SLICE_TIME_BUDGET, 30},
        {JSGC_HIGH_FREQUENCY_TIME_LIMIT, 1500},
        {JSGC_HIGH_FREQUENCY_HIGH_LIMIT, 40},
        {JSGC_HIGH_FREQUENCY_LOW_LIMIT, 0},
        {JSGC_HIGH_FREQUENCY_HEAP_GROWTH_MAX, 300},
        {JSGC_HIGH_FREQUENCY_HEAP_GROWTH_MIN, 120},
        {JSGC_LOW_FREQUENCY_HEAP_GROWTH, 120},
        {JSGC_HIGH_FREQUENCY_TIME_LIMIT, 1500},
        {JSGC_HIGH_FREQUENCY_TIME_LIMIT, 1500},
        {JSGC_HIGH_FREQUENCY_TIME_LIMIT, 1500},
        {JSGC_ALLOCATION_THRESHOLD, 1},
        {JSGC_MODE, JSGC_MODE_INCREMENTAL}
    };

    const JSGCConfig* config = minimal;
    if (availMem > 512) {
        static const JSGCConfig nominal[NumGCConfigs] = {
            {JSGC_MAX_MALLOC_BYTES, 6 * 1024 * 1024},
            {JSGC_SLICE_TIME_BUDGET, 30},
            {JSGC_HIGH_FREQUENCY_TIME_LIMIT, 1000},
            {JSGC_HIGH_FREQUENCY_HIGH_LIMIT, 500},
            {JSGC_HIGH_FREQUENCY_LOW_LIMIT, 100},
            {JSGC_HIGH_FREQUENCY_HEAP_GROWTH_MAX, 300},
            {JSGC_HIGH_FREQUENCY_HEAP_GROWTH_MIN, 150},
            {JSGC_LOW_FREQUENCY_HEAP_GROWTH, 150},
            {JSGC_HIGH_FREQUENCY_TIME_LIMIT, 1500},
            {JSGC_HIGH_FREQUENCY_TIME_LIMIT, 1500},
            {JSGC_HIGH_FREQUENCY_TIME_LIMIT, 1500},
            {JSGC_ALLOCATION_THRESHOLD, 30},
            {JSGC_MODE, JSGC_MODE_ZONE}
        };

        config = nominal;
    }

    for (size_t i = 0; i < NumGCConfigs; i++) {
        JS_SetGCParameter(cx, config[i].key, config[i].value);
    }
}


JS_PUBLIC_API(JSString*)
JS_NewExternalString(JSContext* cx, const char16_t* chars, size_t length,
                     const JSStringFinalizer* fin)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    JSString* s = JSExternalString::new_(cx, chars, length, fin);
    return s;
}

JS_PUBLIC_API(JSString*)
JS_NewMaybeExternalString(JSContext* cx, const char16_t* chars, size_t length,
                          const JSStringFinalizer* fin, bool* allocatedExternal)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    return NewMaybeExternalString(cx, chars, length, fin, allocatedExternal);
}

extern JS_PUBLIC_API(bool)
JS_IsExternalString(JSString* str)
{
    return str->isExternal();
}

extern JS_PUBLIC_API(const JSStringFinalizer*)
JS_GetExternalStringFinalizer(JSString* str)
{
    return str->asExternal().externalFinalizer();
}

static void
SetNativeStackQuotaAndLimit(JSContext* cx, JS::StackKind kind, size_t stackSize)
{
    cx->nativeStackQuota[kind] = stackSize;

#if JS_STACK_GROWTH_DIRECTION > 0
    if (stackSize == 0) {
        cx->nativeStackLimit[kind] = UINTPTR_MAX;
    } else {
        MOZ_ASSERT(cx->nativeStackBase <= size_t(-1) - stackSize);
        cx->nativeStackLimit[kind] = cx->nativeStackBase + stackSize - 1;
    }
#else
    if (stackSize == 0) {
        cx->nativeStackLimit[kind] = 0;
    } else {
        MOZ_ASSERT(cx->nativeStackBase >= stackSize);
        cx->nativeStackLimit[kind] = cx->nativeStackBase - (stackSize - 1);
    }
#endif
}

JS_PUBLIC_API(void)
JS_SetNativeStackQuota(JSContext* cx, size_t systemCodeStackSize, size_t trustedScriptStackSize,
                       size_t untrustedScriptStackSize)
{
    MOZ_ASSERT(!cx->activation());

    if (!trustedScriptStackSize) {
        trustedScriptStackSize = systemCodeStackSize;
    } else {
        MOZ_ASSERT(trustedScriptStackSize < systemCodeStackSize);
    }

    if (!untrustedScriptStackSize) {
        untrustedScriptStackSize = trustedScriptStackSize;
    } else {
        MOZ_ASSERT(untrustedScriptStackSize < trustedScriptStackSize);
    }

    SetNativeStackQuotaAndLimit(cx, JS::StackForSystemCode, systemCodeStackSize);
    SetNativeStackQuotaAndLimit(cx, JS::StackForTrustedScript, trustedScriptStackSize);
    SetNativeStackQuotaAndLimit(cx, JS::StackForUntrustedScript, untrustedScriptStackSize);

    if (cx->isMainThreadContext()) {
        cx->initJitStackLimit();
    }
}

/************************************************************************/

JS_PUBLIC_API(bool)
JS_ValueToId(JSContext* cx, HandleValue value, MutableHandleId idp)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(value);
    return ValueToId<CanGC>(cx, value, idp);
}

JS_PUBLIC_API(bool)
JS_StringToId(JSContext* cx, HandleString string, MutableHandleId idp)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(string);
    RootedValue value(cx, StringValue(string));
    return ValueToId<CanGC>(cx, value, idp);
}

JS_PUBLIC_API(bool)
JS_IdToValue(JSContext* cx, jsid id, MutableHandleValue vp)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(id);
    vp.set(IdToValue(id));
    cx->check(vp);
    return true;
}

JS_PUBLIC_API(bool)
JS::ToPrimitive(JSContext* cx, HandleObject obj, JSType hint, MutableHandleValue vp)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj);
    MOZ_ASSERT(obj != nullptr);
    MOZ_ASSERT(hint == JSTYPE_UNDEFINED || hint == JSTYPE_STRING || hint == JSTYPE_NUMBER);
    vp.setObject(*obj);
    return ToPrimitiveSlow(cx, hint, vp);
}

JS_PUBLIC_API(bool)
JS::GetFirstArgumentAsTypeHint(JSContext* cx, CallArgs args, JSType *result)
{
    if (!args.get(0).isString()) {
        JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_NOT_EXPECTED_TYPE,
                                  "Symbol.toPrimitive",
                                  "\"string\", \"number\", or \"default\"",
                                  InformalValueTypeName(args.get(0)));
        return false;
    }

    RootedString str(cx, args.get(0).toString());
    bool match;

    if (!EqualStrings(cx, str, cx->names().default_, &match)) {
        return false;
    }
    if (match) {
        *result = JSTYPE_UNDEFINED;
        return true;
    }

    if (!EqualStrings(cx, str, cx->names().string, &match)) {
        return false;
    }
    if (match) {
        *result = JSTYPE_STRING;
        return true;
    }

    if (!EqualStrings(cx, str, cx->names().number, &match)) {
        return false;
    }
    if (match) {
        *result = JSTYPE_NUMBER;
        return true;
    }

    UniqueChars bytes;
    const char* source = ValueToSourceForError(cx, args.get(0), bytes);
    if (!source) {
        ReportOutOfMemory(cx);
        return false;
    }

    JS_ReportErrorNumberUTF8(cx, GetErrorMessage, nullptr, JSMSG_NOT_EXPECTED_TYPE,
                             "Symbol.toPrimitive",
                             "\"string\", \"number\", or \"default\"", source);
    return false;
}

JS_PUBLIC_API(JSObject*)
JS_InitClass(JSContext* cx, HandleObject obj, HandleObject parent_proto,
             const JSClass* clasp, JSNative constructor, unsigned nargs,
             const JSPropertySpec* ps, const JSFunctionSpec* fs,
             const JSPropertySpec* static_ps, const JSFunctionSpec* static_fs)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj, parent_proto);
    return InitClass(cx, obj, parent_proto, Valueify(clasp), constructor,
                     nargs, ps, fs, static_ps, static_fs);
}

JS_PUBLIC_API(bool)
JS_LinkConstructorAndPrototype(JSContext* cx, HandleObject ctor, HandleObject proto)
{
    return LinkConstructorAndPrototype(cx, ctor, proto);
}

JS_PUBLIC_API(const JSClass*)
JS_GetClass(JSObject* obj)
{
    return obj->getJSClass();
}

JS_PUBLIC_API(bool)
JS_InstanceOf(JSContext* cx, HandleObject obj, const JSClass* clasp, CallArgs* args)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
#ifdef DEBUG
    if (args) {
        cx->check(obj);
        cx->check(args->thisv(), args->calleev());
    }
#endif
    if (!obj || obj->getJSClass() != clasp) {
        if (args) {
            ReportIncompatibleMethod(cx, *args, Valueify(clasp));
        }
        return false;
    }
    return true;
}

JS_PUBLIC_API(bool)
JS_HasInstance(JSContext* cx, HandleObject obj, HandleValue value, bool* bp)
{
    AssertHeapIsIdle();
    cx->check(obj, value);
    return HasInstance(cx, obj, value, bp);
}

JS_PUBLIC_API(void*)
JS_GetPrivate(JSObject* obj)
{
    /* This function can be called by a finalizer. */
    return obj->as<NativeObject>().getPrivate();
}

JS_PUBLIC_API(void)
JS_SetPrivate(JSObject* obj, void* data)
{
    /* This function can be called by a finalizer. */
    obj->as<NativeObject>().setPrivate(data);
}

JS_PUBLIC_API(void*)
JS_GetInstancePrivate(JSContext* cx, HandleObject obj, const JSClass* clasp, CallArgs* args)
{
    if (!JS_InstanceOf(cx, obj, clasp, args)) {
        return nullptr;
    }
    return obj->as<NativeObject>().getPrivate();
}

JS_PUBLIC_API(JSObject*)
JS_GetConstructor(JSContext* cx, HandleObject proto)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(proto);

    RootedValue cval(cx);
    if (!GetProperty(cx, proto, proto, cx->names().constructor, &cval)) {
        return nullptr;
    }
    if (!IsFunctionObject(cval)) {
        JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_NO_CONSTRUCTOR,
                                  proto->getClass()->name);
        return nullptr;
    }
    return &cval.toObject();
}

bool
JS::RealmBehaviors::extraWarnings(JSContext* cx) const
{
    return extraWarningsOverride_.get(cx->options().extraWarnings());
}

JS::RealmCreationOptions&
JS::RealmCreationOptions::setNewCompartmentInSystemZone()
{
    compSpec_ = CompartmentSpecifier::NewCompartmentInSystemZone;
    comp_ = nullptr;
    return *this;
}

JS::RealmCreationOptions&
JS::RealmCreationOptions::setNewCompartmentInExistingZone(JSObject* obj)
{
    compSpec_ = CompartmentSpecifier::NewCompartmentInExistingZone;
    zone_ = obj->zone();
    return *this;
}

JS::RealmCreationOptions&
JS::RealmCreationOptions::setExistingCompartment(JSObject* obj)
{
    compSpec_ = CompartmentSpecifier::ExistingCompartment;
    comp_ = obj->compartment();
    return *this;
}

JS::RealmCreationOptions&
JS::RealmCreationOptions::setNewCompartmentAndZone()
{
    compSpec_ = CompartmentSpecifier::NewCompartmentAndZone;
    comp_ = nullptr;
    return *this;
}

const JS::RealmCreationOptions&
JS::RealmCreationOptionsRef(Realm* realm)
{
    return realm->creationOptions();
}

const JS::RealmCreationOptions&
JS::RealmCreationOptionsRef(JSContext* cx)
{
    return cx->realm()->creationOptions();
}

bool
JS::RealmCreationOptions::getSharedMemoryAndAtomicsEnabled() const
{
#if defined(ENABLE_SHARED_ARRAY_BUFFER)
    return sharedMemoryAndAtomics_;
#else
    return false;
#endif
}

JS::RealmCreationOptions&
JS::RealmCreationOptions::setSharedMemoryAndAtomicsEnabled(bool flag)
{
#if defined(ENABLE_SHARED_ARRAY_BUFFER)
    sharedMemoryAndAtomics_ = flag;
#endif
    return *this;
}

JS::RealmBehaviors&
JS::RealmBehaviorsRef(JS::Realm* realm)
{
    return realm->behaviors();
}

JS::RealmBehaviors&
JS::RealmBehaviorsRef(JSContext* cx)
{
    return cx->realm()->behaviors();
}

JS_PUBLIC_API(JSObject*)
JS_NewGlobalObject(JSContext* cx, const JSClass* clasp, JSPrincipals* principals,
                   JS::OnNewGlobalHookOption hookOption,
                   const JS::RealmOptions& options)
{
    MOZ_RELEASE_ASSERT(cx->runtime()->hasInitializedSelfHosting(),
                       "Must call JS::InitSelfHostedCode() before creating a global");

    AssertHeapIsIdle();
    CHECK_THREAD(cx);

    return GlobalObject::new_(cx, Valueify(clasp), principals, hookOption, options);
}

JS_PUBLIC_API(void)
JS_GlobalObjectTraceHook(JSTracer* trc, JSObject* global)
{
    GlobalObject* globalObj = &global->as<GlobalObject>();
    Realm* globalRealm = globalObj->realm();

    // Off thread parsing and compilation tasks create a dummy global which is
    // then merged back into the host realm. Since it used to be a global, it
    // will still have this trace hook, but it does not have a meaning relative
    // to its new realm. We can safely skip it.
    //
    // Similarly, if we GC when creating the global, we may not have set that
    // global's realm's global pointer yet. In this case, the realm will not yet
    // contain anything that needs to be traced.
    if (globalRealm->unsafeUnbarrieredMaybeGlobal() != globalObj) {
        return;
    }

    // Trace the realm for any GC things that should only stick around if we
    // know the global is live.
    globalRealm->traceGlobal(trc);

    if (JSTraceOp trace = globalRealm->creationOptions().getTrace()) {
        trace(trc, global);
    }
}

JS_PUBLIC_API(void)
JS_FireOnNewGlobalObject(JSContext* cx, JS::HandleObject global)
{
    // This hook is infallible, because we don't really want arbitrary script
    // to be able to throw errors during delicate global creation routines.
    // This infallibility will eat OOM and slow script, but if that happens
    // we'll likely run up into them again soon in a fallible context.
    cx->check(global);
    Rooted<js::GlobalObject*> globalObject(cx, &global->as<GlobalObject>());
    Debugger::onNewGlobalObject(cx, globalObject);
}

JS_PUBLIC_API(JSObject*)
JS_NewObject(JSContext* cx, const JSClass* jsclasp)
{
    MOZ_ASSERT(!cx->zone()->isAtomsZone());
    AssertHeapIsIdle();
    CHECK_THREAD(cx);

    const Class* clasp = Valueify(jsclasp);
    if (!clasp) {
        clasp = &PlainObject::class_;    /* default class is Object */
    }

    MOZ_ASSERT(clasp != &JSFunction::class_);
    MOZ_ASSERT(!(clasp->flags & JSCLASS_IS_GLOBAL));

    return NewBuiltinClassInstance(cx, clasp);
}

JS_PUBLIC_API(JSObject*)
JS_NewObjectWithGivenProto(JSContext* cx, const JSClass* jsclasp, HandleObject proto)
{
    MOZ_ASSERT(!cx->zone()->isAtomsZone());
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(proto);

    const Class* clasp = Valueify(jsclasp);
    if (!clasp) {
        clasp = &PlainObject::class_;    /* default class is Object */
    }

    MOZ_ASSERT(clasp != &JSFunction::class_);
    MOZ_ASSERT(!(clasp->flags & JSCLASS_IS_GLOBAL));

    return NewObjectWithGivenProto(cx, clasp, proto);
}

JS_PUBLIC_API(JSObject*)
JS_NewPlainObject(JSContext* cx)
{
    MOZ_ASSERT(!cx->zone()->isAtomsZone());
    AssertHeapIsIdle();
    CHECK_THREAD(cx);

    return NewBuiltinClassInstance<PlainObject>(cx);
}

JS_PUBLIC_API(JSObject*)
JS_NewObjectForConstructor(JSContext* cx, const JSClass* clasp, const CallArgs& args)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);

    Value callee = args.calleev();
    cx->check(callee);
    RootedObject obj(cx, &callee.toObject());
    return CreateThis(cx, Valueify(clasp), obj);
}

JS_PUBLIC_API(bool)
JS_IsNative(JSObject* obj)
{
    return obj->isNative();
}

JS_PUBLIC_API(void)
JS::AssertObjectBelongsToCurrentThread(JSObject* obj)
{
    JSRuntime* rt = obj->compartment()->runtimeFromAnyThread();
    MOZ_RELEASE_ASSERT(CurrentThreadCanAccessRuntime(rt));
}


/*** Standard internal methods *******************************************************************/

JS_PUBLIC_API(bool)
JS_GetPrototype(JSContext* cx, HandleObject obj, MutableHandleObject result)
{
    cx->check(obj);
    return GetPrototype(cx, obj, result);
}

JS_PUBLIC_API(bool)
JS_SetPrototype(JSContext* cx, HandleObject obj, HandleObject proto)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj, proto);

    return SetPrototype(cx, obj, proto);
}

JS_PUBLIC_API(bool)
JS_GetPrototypeIfOrdinary(JSContext* cx, HandleObject obj, bool* isOrdinary,
                          MutableHandleObject result)
{
    cx->check(obj);
    return GetPrototypeIfOrdinary(cx, obj, isOrdinary, result);
}

JS_PUBLIC_API(bool)
JS_IsExtensible(JSContext* cx, HandleObject obj, bool* extensible)
{
    cx->check(obj);
    return IsExtensible(cx, obj, extensible);
}

JS_PUBLIC_API(bool)
JS_PreventExtensions(JSContext* cx, JS::HandleObject obj, ObjectOpResult& result)
{
    cx->check(obj);
    return PreventExtensions(cx, obj, result);
}

JS_PUBLIC_API(bool)
JS_SetImmutablePrototype(JSContext *cx, JS::HandleObject obj, bool *succeeded)
{
    cx->check(obj);
    return SetImmutablePrototype(cx, obj, succeeded);
}

JS_PUBLIC_API(bool)
JS_GetOwnPropertyDescriptorById(JSContext* cx, HandleObject obj, HandleId id,
                                MutableHandle<PropertyDescriptor> desc)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj, id);

    return GetOwnPropertyDescriptor(cx, obj, id, desc);
}

JS_PUBLIC_API(bool)
JS_GetOwnPropertyDescriptor(JSContext* cx, HandleObject obj, const char* name,
                            MutableHandle<PropertyDescriptor> desc)
{
    JSAtom* atom = Atomize(cx, name, strlen(name));
    if (!atom) {
        return false;
    }
    RootedId id(cx, AtomToId(atom));
    return JS_GetOwnPropertyDescriptorById(cx, obj, id, desc);
}

JS_PUBLIC_API(bool)
JS_GetOwnUCPropertyDescriptor(JSContext* cx, HandleObject obj, const char16_t* name, size_t namelen,
                              MutableHandle<PropertyDescriptor> desc)
{
    JSAtom* atom = AtomizeChars(cx, name, namelen);
    if (!atom) {
        return false;
    }
    RootedId id(cx, AtomToId(atom));
    return JS_GetOwnPropertyDescriptorById(cx, obj, id, desc);
}

JS_PUBLIC_API(bool)
JS_GetPropertyDescriptorById(JSContext* cx, HandleObject obj, HandleId id,
                             MutableHandle<PropertyDescriptor> desc)
{
    cx->check(obj, id);
    return GetPropertyDescriptor(cx, obj, id, desc);
}

JS_PUBLIC_API(bool)
JS_GetPropertyDescriptor(JSContext* cx, HandleObject obj, const char* name,
                         MutableHandle<PropertyDescriptor> desc)
{
    JSAtom* atom = Atomize(cx, name, strlen(name));
    if (!atom) {
        return false;
    }
    RootedId id(cx, AtomToId(atom));
    return JS_GetPropertyDescriptorById(cx, obj, id, desc);
}

JS_PUBLIC_API(bool)
JS_GetUCPropertyDescriptor(JSContext* cx, HandleObject obj, const char16_t* name, size_t namelen,
                           MutableHandle<PropertyDescriptor> desc)
{
    JSAtom* atom = AtomizeChars(cx, name, namelen);
    if (!atom) {
        return false;
    }
    RootedId id(cx, AtomToId(atom));
    return JS_GetPropertyDescriptorById(cx, obj, id, desc);
}

static bool
DefinePropertyByDescriptor(JSContext* cx, HandleObject obj, HandleId id,
                           Handle<PropertyDescriptor> desc, ObjectOpResult& result)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj, id, desc);
    return DefineProperty(cx, obj, id, desc, result);
}

JS_PUBLIC_API(bool)
JS_DefinePropertyById(JSContext* cx, HandleObject obj, HandleId id,
                      Handle<PropertyDescriptor> desc, ObjectOpResult& result)
{
    return DefinePropertyByDescriptor(cx, obj, id, desc, result);
}

JS_PUBLIC_API(bool)
JS_DefinePropertyById(JSContext* cx, HandleObject obj, HandleId id,
                      Handle<PropertyDescriptor> desc)
{
    ObjectOpResult result;
    return DefinePropertyByDescriptor(cx, obj, id, desc, result) &&
           result.checkStrict(cx, obj, id);
}

static bool
DefineAccessorPropertyById(JSContext* cx, HandleObject obj, HandleId id,
                           HandleObject getter, HandleObject setter, unsigned attrs)
{
    MOZ_ASSERT_IF(getter, attrs & JSPROP_GETTER);
    MOZ_ASSERT_IF(setter, attrs & JSPROP_SETTER);

    // JSPROP_READONLY has no meaning when accessors are involved. Ideally we'd
    // throw if this happens, but we've accepted it for long enough that it's
    // not worth trying to make callers change their ways. Just flip it off on
    // its way through the API layer so that we can enforce this internally.
    if (attrs & (JSPROP_GETTER | JSPROP_SETTER)) {
        attrs &= ~JSPROP_READONLY;
    }

    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj, id, getter, setter);

    return js::DefineAccessorProperty(cx, obj, id, getter, setter, attrs);
}

static bool
DefineAccessorPropertyById(JSContext* cx, HandleObject obj, HandleId id,
                           const JSNativeWrapper& get, const JSNativeWrapper& set,
                           unsigned attrs)
{
    // Getter/setter are both possibly-null JSNatives. Wrap them in JSFunctions.

    MOZ_ASSERT(!(attrs & (JSPROP_GETTER | JSPROP_SETTER)));

    RootedFunction getter(cx);
    if (get.op) {
        RootedAtom atom(cx, IdToFunctionName(cx, id, FunctionPrefixKind::Get));
        if (!atom) {
            return false;
        }
        getter = NewNativeFunction(cx, get.op, 0, atom);
        if (!getter) {
            return false;
        }

        if (get.info) {
            getter->setJitInfo(get.info);
        }

        attrs |= JSPROP_GETTER;
    }

    RootedFunction setter(cx);
    if (set.op) {
        RootedAtom atom(cx, IdToFunctionName(cx, id, FunctionPrefixKind::Set));
        if (!atom) {
            return false;
        }
        setter = NewNativeFunction(cx, set.op, 1, atom);
        if (!setter) {
            return false;
        }

        if (set.info) {
            setter->setJitInfo(set.info);
        }

        attrs |= JSPROP_SETTER;
    }

    return DefineAccessorPropertyById(cx, obj, id, getter, setter, attrs);
}


static bool
DefineDataPropertyById(JSContext* cx, HandleObject obj, HandleId id, HandleValue value,
                       unsigned attrs)
{
    MOZ_ASSERT(!(attrs & (JSPROP_GETTER | JSPROP_SETTER)));

    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj, id, value);

    return js::DefineDataProperty(cx, obj, id, value, attrs);
}

/*
 * Wrapper functions to create wrappers with no corresponding JSJitInfo from API
 * function arguments.
 */
static JSNativeWrapper
NativeOpWrapper(Native native)
{
    JSNativeWrapper ret;
    ret.op = native;
    ret.info = nullptr;
    return ret;
}

JS_PUBLIC_API(bool)
JS_DefinePropertyById(JSContext* cx, HandleObject obj, HandleId id, HandleValue value,
                      unsigned attrs)
{
    return DefineDataPropertyById(cx, obj, id, value, attrs);
}

JS_PUBLIC_API(bool)
JS_DefinePropertyById(JSContext* cx, HandleObject obj, HandleId id, Native getter, Native setter,
                      unsigned attrs)
{
    return DefineAccessorPropertyById(cx, obj, id,
                                      NativeOpWrapper(getter), NativeOpWrapper(setter),
                                      attrs);
}

JS_PUBLIC_API(bool)
JS_DefinePropertyById(JSContext* cx, HandleObject obj, HandleId id, HandleObject getter,
                      HandleObject setter, unsigned attrs)
{
    return DefineAccessorPropertyById(cx, obj, id, getter, setter, attrs);
}

JS_PUBLIC_API(bool)
JS_DefinePropertyById(JSContext* cx, HandleObject obj, HandleId id, HandleObject valueArg,
                      unsigned attrs)
{
    RootedValue value(cx, ObjectValue(*valueArg));
    return DefineDataPropertyById(cx, obj, id, value, attrs);
}

JS_PUBLIC_API(bool)
JS_DefinePropertyById(JSContext* cx, HandleObject obj, HandleId id, HandleString valueArg,
                      unsigned attrs)
{
    RootedValue value(cx, StringValue(valueArg));
    return DefineDataPropertyById(cx, obj, id, value, attrs);
}

JS_PUBLIC_API(bool)
JS_DefinePropertyById(JSContext* cx, HandleObject obj, HandleId id, int32_t valueArg,
                      unsigned attrs)
{
    Value value = Int32Value(valueArg);
    return DefineDataPropertyById(cx, obj, id, HandleValue::fromMarkedLocation(&value), attrs);
}

JS_PUBLIC_API(bool)
JS_DefinePropertyById(JSContext* cx, HandleObject obj, HandleId id, uint32_t valueArg,
                      unsigned attrs)
{
    Value value = NumberValue(valueArg);
    return DefineDataPropertyById(cx, obj, id, HandleValue::fromMarkedLocation(&value), attrs);
}

JS_PUBLIC_API(bool)
JS_DefinePropertyById(JSContext* cx, HandleObject obj, HandleId id, double valueArg,
                      unsigned attrs)
{
    Value value = NumberValue(valueArg);
    return DefineDataPropertyById(cx, obj, id, HandleValue::fromMarkedLocation(&value), attrs);
}

static bool
DefineDataProperty(JSContext* cx, HandleObject obj, const char* name, HandleValue value,
                   unsigned attrs)
{
    JSAtom* atom = Atomize(cx, name, strlen(name));
    if (!atom) {
        return false;
    }
    RootedId id(cx, AtomToId(atom));

    return DefineDataPropertyById(cx, obj, id, value, attrs);
}

JS_PUBLIC_API(bool)
JS_DefineProperty(JSContext* cx, HandleObject obj, const char* name, HandleValue value,
                  unsigned attrs)
{
    return DefineDataProperty(cx, obj, name, value, attrs);
}

JS_PUBLIC_API(bool)
JS_DefineProperty(JSContext* cx, HandleObject obj, const char* name, Native getter, Native setter,
                  unsigned attrs)
{
    JSAtom* atom = Atomize(cx, name, strlen(name));
    if (!atom) {
        return false;
    }
    RootedId id(cx, AtomToId(atom));
    return DefineAccessorPropertyById(cx, obj, id, NativeOpWrapper(getter),
                                      NativeOpWrapper(setter), attrs);
}

JS_PUBLIC_API(bool)
JS_DefineProperty(JSContext* cx, HandleObject obj, const char* name, HandleObject getter,
                  HandleObject setter, unsigned attrs)
{
    JSAtom* atom = Atomize(cx, name, strlen(name));
    if (!atom) {
        return false;
    }
    RootedId id(cx, AtomToId(atom));

    return DefineAccessorPropertyById(cx, obj, id, getter, setter, attrs);
}

JS_PUBLIC_API(bool)
JS_DefineProperty(JSContext* cx, HandleObject obj, const char* name, HandleObject valueArg,
                  unsigned attrs)
{
    RootedValue value(cx, ObjectValue(*valueArg));
    return DefineDataProperty(cx, obj, name, value, attrs);
}

JS_PUBLIC_API(bool)
JS_DefineProperty(JSContext* cx, HandleObject obj, const char* name, HandleString valueArg,
                  unsigned attrs)
{
    RootedValue value(cx, StringValue(valueArg));
    return DefineDataProperty(cx, obj, name, value, attrs);
}

JS_PUBLIC_API(bool)
JS_DefineProperty(JSContext* cx, HandleObject obj, const char* name, int32_t valueArg,
                  unsigned attrs)
{
    Value value = Int32Value(valueArg);
    return DefineDataProperty(cx, obj, name, HandleValue::fromMarkedLocation(&value), attrs);
}

JS_PUBLIC_API(bool)
JS_DefineProperty(JSContext* cx, HandleObject obj, const char* name, uint32_t valueArg,
                  unsigned attrs)
{
    Value value = NumberValue(valueArg);
    return DefineDataProperty(cx, obj, name, HandleValue::fromMarkedLocation(&value), attrs);
}

JS_PUBLIC_API(bool)
JS_DefineProperty(JSContext* cx, HandleObject obj, const char* name, double valueArg,
                  unsigned attrs)
{
    Value value = NumberValue(valueArg);
    return DefineDataProperty(cx, obj, name, HandleValue::fromMarkedLocation(&value), attrs);
}

#define AUTO_NAMELEN(s,n)   (((n) == (size_t)-1) ? js_strlen(s) : (n))

JS_PUBLIC_API(bool)
JS_DefineUCProperty(JSContext* cx, HandleObject obj, const char16_t* name, size_t namelen,
                    Handle<PropertyDescriptor> desc,
                    ObjectOpResult& result)
{
    JSAtom* atom = AtomizeChars(cx, name, AUTO_NAMELEN(name, namelen));
    if (!atom) {
        return false;
    }
    RootedId id(cx, AtomToId(atom));
    return DefinePropertyByDescriptor(cx, obj, id, desc, result);
}

JS_PUBLIC_API(bool)
JS_DefineUCProperty(JSContext* cx, HandleObject obj, const char16_t* name, size_t namelen,
                    Handle<PropertyDescriptor> desc)
{
    JSAtom* atom = AtomizeChars(cx, name, AUTO_NAMELEN(name, namelen));
    if (!atom) {
        return false;
    }
    RootedId id(cx, AtomToId(atom));
    ObjectOpResult result;
    return DefinePropertyByDescriptor(cx, obj, id, desc, result) &&
           result.checkStrict(cx, obj, id);
}

static bool
DefineUCDataProperty(JSContext* cx, HandleObject obj, const char16_t* name, size_t namelen,
                     HandleValue value, unsigned attrs)
{
    JSAtom* atom = AtomizeChars(cx, name, AUTO_NAMELEN(name, namelen));
    if (!atom) {
        return false;
    }
    RootedId id(cx, AtomToId(atom));
    return DefineDataPropertyById(cx, obj, id, value, attrs);
}

JS_PUBLIC_API(bool)
JS_DefineUCProperty(JSContext* cx, HandleObject obj, const char16_t* name, size_t namelen,
                    HandleValue value, unsigned attrs)
{
    return DefineUCDataProperty(cx, obj, name, namelen, value, attrs);
}

JS_PUBLIC_API(bool)
JS_DefineUCProperty(JSContext* cx, HandleObject obj, const char16_t* name, size_t namelen,
                    HandleObject getter, HandleObject setter, unsigned attrs)
{
    JSAtom* atom = AtomizeChars(cx, name, AUTO_NAMELEN(name, namelen));
    if (!atom) {
        return false;
    }
    RootedId id(cx, AtomToId(atom));
    return DefineAccessorPropertyById(cx, obj, id, getter, setter, attrs);
}

JS_PUBLIC_API(bool)
JS_DefineUCProperty(JSContext* cx, HandleObject obj, const char16_t* name, size_t namelen,
                    HandleObject valueArg, unsigned attrs)
{
    RootedValue value(cx, ObjectValue(*valueArg));
    return DefineUCDataProperty(cx, obj, name, namelen, value, attrs);
}

JS_PUBLIC_API(bool)
JS_DefineUCProperty(JSContext* cx, HandleObject obj, const char16_t* name, size_t namelen,
                    HandleString valueArg, unsigned attrs)
{
    RootedValue value(cx, StringValue(valueArg));
    return DefineUCDataProperty(cx, obj, name, namelen, value, attrs);
}

JS_PUBLIC_API(bool)
JS_DefineUCProperty(JSContext* cx, HandleObject obj, const char16_t* name, size_t namelen,
                    int32_t valueArg, unsigned attrs)
{
    Value value = Int32Value(valueArg);
    return DefineUCDataProperty(cx, obj, name, namelen, HandleValue::fromMarkedLocation(&value),
                                attrs);
}

JS_PUBLIC_API(bool)
JS_DefineUCProperty(JSContext* cx, HandleObject obj, const char16_t* name, size_t namelen,
                    uint32_t valueArg, unsigned attrs)
{
    Value value = NumberValue(valueArg);
    return DefineUCDataProperty(cx, obj, name, namelen, HandleValue::fromMarkedLocation(&value),
                                attrs);
}

JS_PUBLIC_API(bool)
JS_DefineUCProperty(JSContext* cx, HandleObject obj, const char16_t* name, size_t namelen,
                    double valueArg, unsigned attrs)
{
    Value value = NumberValue(valueArg);
    return DefineUCDataProperty(cx, obj, name, namelen, HandleValue::fromMarkedLocation(&value),
                                attrs);
}

static bool
DefineDataElement(JSContext* cx, HandleObject obj, uint32_t index, HandleValue value,
                  unsigned attrs)
{
    cx->check(obj, value);
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    RootedId id(cx);
    if (!IndexToId(cx, index, &id)) {
        return false;
    }
    return DefineDataPropertyById(cx, obj, id, value, attrs);
}

JS_PUBLIC_API(bool)
JS_DefineElement(JSContext* cx, HandleObject obj, uint32_t index, HandleValue value,
                 unsigned attrs)
{
    return ::DefineDataElement(cx, obj, index, value, attrs);
}

JS_PUBLIC_API(bool)
JS_DefineElement(JSContext* cx, HandleObject obj, uint32_t index, HandleObject getter,
                 HandleObject setter, unsigned attrs)
{
    RootedId id(cx);
    if (!IndexToId(cx, index, &id)) {
        return false;
    }
    return DefineAccessorPropertyById(cx, obj, id, getter, setter, attrs);
}

JS_PUBLIC_API(bool)
JS_DefineElement(JSContext* cx, HandleObject obj, uint32_t index, HandleObject valueArg,
                 unsigned attrs)
{
    RootedValue value(cx, ObjectValue(*valueArg));
    return ::DefineDataElement(cx, obj, index, value, attrs);
}

JS_PUBLIC_API(bool)
JS_DefineElement(JSContext* cx, HandleObject obj, uint32_t index, HandleString valueArg,
                 unsigned attrs)
{
    RootedValue value(cx, StringValue(valueArg));
    return ::DefineDataElement(cx, obj, index, value, attrs);
}

JS_PUBLIC_API(bool)
JS_DefineElement(JSContext* cx, HandleObject obj, uint32_t index, int32_t valueArg,
                 unsigned attrs)
{
    Value value = Int32Value(valueArg);
    return ::DefineDataElement(cx, obj, index, HandleValue::fromMarkedLocation(&value), attrs);
}

JS_PUBLIC_API(bool)
JS_DefineElement(JSContext* cx, HandleObject obj, uint32_t index, uint32_t valueArg,
                 unsigned attrs)
{
    Value value = NumberValue(valueArg);
    return ::DefineDataElement(cx, obj, index, HandleValue::fromMarkedLocation(&value), attrs);
}

JS_PUBLIC_API(bool)
JS_DefineElement(JSContext* cx, HandleObject obj, uint32_t index, double valueArg,
                 unsigned attrs)
{
    Value value = NumberValue(valueArg);
    return ::DefineDataElement(cx, obj, index, HandleValue::fromMarkedLocation(&value), attrs);
}

JS_PUBLIC_API(bool)
JS_HasPropertyById(JSContext* cx, HandleObject obj, HandleId id, bool* foundp)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj, id);

    return HasProperty(cx, obj, id, foundp);
}

JS_PUBLIC_API(bool)
JS_HasProperty(JSContext* cx, HandleObject obj, const char* name, bool* foundp)
{
    JSAtom* atom = Atomize(cx, name, strlen(name));
    if (!atom) {
        return false;
    }
    RootedId id(cx, AtomToId(atom));
    return JS_HasPropertyById(cx, obj, id, foundp);
}

JS_PUBLIC_API(bool)
JS_HasUCProperty(JSContext* cx, HandleObject obj, const char16_t* name, size_t namelen, bool* foundp)
{
    JSAtom* atom = AtomizeChars(cx, name, AUTO_NAMELEN(name, namelen));
    if (!atom) {
        return false;
    }
    RootedId id(cx, AtomToId(atom));
    return JS_HasPropertyById(cx, obj, id, foundp);
}

JS_PUBLIC_API(bool)
JS_HasElement(JSContext* cx, HandleObject obj, uint32_t index, bool* foundp)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    RootedId id(cx);
    if (!IndexToId(cx, index, &id)) {
        return false;
    }
    return JS_HasPropertyById(cx, obj, id, foundp);
}

JS_PUBLIC_API(bool)
JS_HasOwnPropertyById(JSContext* cx, HandleObject obj, HandleId id, bool* foundp)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj, id);

    return HasOwnProperty(cx, obj, id, foundp);
}

JS_PUBLIC_API(bool)
JS_HasOwnProperty(JSContext* cx, HandleObject obj, const char* name, bool* foundp)
{
    JSAtom* atom = Atomize(cx, name, strlen(name));
    if (!atom) {
        return false;
    }
    RootedId id(cx, AtomToId(atom));
    return JS_HasOwnPropertyById(cx, obj, id, foundp);
}

JS_PUBLIC_API(bool)
JS_ForwardGetPropertyTo(JSContext* cx, HandleObject obj, HandleId id, HandleValue receiver,
                        MutableHandleValue vp)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj, id, receiver);

    return GetProperty(cx, obj, receiver, id, vp);
}

JS_PUBLIC_API(bool)
JS_ForwardGetElementTo(JSContext* cx, HandleObject obj, uint32_t index, HandleObject receiver,
                       MutableHandleValue vp)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj);

    return GetElement(cx, obj, receiver, index, vp);
}

JS_PUBLIC_API(bool)
JS_GetPropertyById(JSContext* cx, HandleObject obj, HandleId id, MutableHandleValue vp)
{
    RootedValue receiver(cx, ObjectValue(*obj));
    return JS_ForwardGetPropertyTo(cx, obj, id, receiver, vp);
}

JS_PUBLIC_API(bool)
JS_GetProperty(JSContext* cx, HandleObject obj, const char* name, MutableHandleValue vp)
{
    JSAtom* atom = Atomize(cx, name, strlen(name));
    if (!atom) {
        return false;
    }
    RootedId id(cx, AtomToId(atom));
    return JS_GetPropertyById(cx, obj, id, vp);
}

JS_PUBLIC_API(bool)
JS_GetUCProperty(JSContext* cx, HandleObject obj, const char16_t* name, size_t namelen,
                 MutableHandleValue vp)
{
    JSAtom* atom = AtomizeChars(cx, name, AUTO_NAMELEN(name, namelen));
    if (!atom) {
        return false;
    }
    RootedId id(cx, AtomToId(atom));
    return JS_GetPropertyById(cx, obj, id, vp);
}

JS_PUBLIC_API(bool)
JS_GetElement(JSContext* cx, HandleObject objArg, uint32_t index, MutableHandleValue vp)
{
    return JS_ForwardGetElementTo(cx, objArg, index, objArg, vp);
}

JS_PUBLIC_API(bool)
JS_ForwardSetPropertyTo(JSContext* cx, HandleObject obj, HandleId id, HandleValue v,
                        HandleValue receiver, ObjectOpResult& result)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj, id, v, receiver);

    return SetProperty(cx, obj, id, v, receiver, result);
}

JS_PUBLIC_API(bool)
JS_SetPropertyById(JSContext* cx, HandleObject obj, HandleId id, HandleValue v)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj, id, v);

    RootedValue receiver(cx, ObjectValue(*obj));
    ObjectOpResult ignored;
    return SetProperty(cx, obj, id, v, receiver, ignored);
}

JS_PUBLIC_API(bool)
JS_SetProperty(JSContext* cx, HandleObject obj, const char* name, HandleValue v)
{
    JSAtom* atom = Atomize(cx, name, strlen(name));
    if (!atom) {
        return false;
    }
    RootedId id(cx, AtomToId(atom));
    return JS_SetPropertyById(cx, obj, id, v);
}

JS_PUBLIC_API(bool)
JS_SetUCProperty(JSContext* cx, HandleObject obj, const char16_t* name, size_t namelen,
                 HandleValue v)
{
    JSAtom* atom = AtomizeChars(cx, name, AUTO_NAMELEN(name, namelen));
    if (!atom) {
        return false;
    }
    RootedId id(cx, AtomToId(atom));
    return JS_SetPropertyById(cx, obj, id, v);
}

static bool
SetElement(JSContext* cx, HandleObject obj, uint32_t index, HandleValue v)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj, v);

    RootedValue receiver(cx, ObjectValue(*obj));
    ObjectOpResult ignored;
    return SetElement(cx, obj, index, v, receiver, ignored);
}

JS_PUBLIC_API(bool)
JS_SetElement(JSContext* cx, HandleObject obj, uint32_t index, HandleValue v)
{
    return SetElement(cx, obj, index, v);
}

JS_PUBLIC_API(bool)
JS_SetElement(JSContext* cx, HandleObject obj, uint32_t index, HandleObject v)
{
    RootedValue value(cx, ObjectOrNullValue(v));
    return SetElement(cx, obj, index, value);
}

JS_PUBLIC_API(bool)
JS_SetElement(JSContext* cx, HandleObject obj, uint32_t index, HandleString v)
{
    RootedValue value(cx, StringValue(v));
    return SetElement(cx, obj, index, value);
}

JS_PUBLIC_API(bool)
JS_SetElement(JSContext* cx, HandleObject obj, uint32_t index, int32_t v)
{
    RootedValue value(cx, NumberValue(v));
    return SetElement(cx, obj, index, value);
}

JS_PUBLIC_API(bool)
JS_SetElement(JSContext* cx, HandleObject obj, uint32_t index, uint32_t v)
{
    RootedValue value(cx, NumberValue(v));
    return SetElement(cx, obj, index, value);
}

JS_PUBLIC_API(bool)
JS_SetElement(JSContext* cx, HandleObject obj, uint32_t index, double v)
{
    RootedValue value(cx, NumberValue(v));
    return SetElement(cx, obj, index, value);
}

JS_PUBLIC_API(bool)
JS_DeletePropertyById(JSContext* cx, HandleObject obj, HandleId id, ObjectOpResult& result)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj, id);

    return DeleteProperty(cx, obj, id, result);
}

JS_PUBLIC_API(bool)
JS_DeleteProperty(JSContext* cx, HandleObject obj, const char* name, ObjectOpResult& result)
{
    CHECK_THREAD(cx);
    cx->check(obj);

    JSAtom* atom = Atomize(cx, name, strlen(name));
    if (!atom) {
        return false;
    }
    RootedId id(cx, AtomToId(atom));
    return DeleteProperty(cx, obj, id, result);
}

JS_PUBLIC_API(bool)
JS_DeleteUCProperty(JSContext* cx, HandleObject obj, const char16_t* name, size_t namelen,
                    ObjectOpResult& result)
{
    CHECK_THREAD(cx);
    cx->check(obj);

    JSAtom* atom = AtomizeChars(cx, name, AUTO_NAMELEN(name, namelen));
    if (!atom) {
        return false;
    }
    RootedId id(cx, AtomToId(atom));
    return DeleteProperty(cx, obj, id, result);
}

JS_PUBLIC_API(bool)
JS_DeleteElement(JSContext* cx, HandleObject obj, uint32_t index, ObjectOpResult& result)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj);

    return DeleteElement(cx, obj, index, result);
}

JS_PUBLIC_API(bool)
JS_DeletePropertyById(JSContext* cx, HandleObject obj, HandleId id)
{
    ObjectOpResult ignored;
    return JS_DeletePropertyById(cx, obj, id, ignored);
}

JS_PUBLIC_API(bool)
JS_DeleteProperty(JSContext* cx, HandleObject obj, const char* name)
{
    ObjectOpResult ignored;
    return JS_DeleteProperty(cx, obj, name, ignored);
}

JS_PUBLIC_API(bool)
JS_DeleteElement(JSContext* cx, HandleObject obj, uint32_t index)
{
    ObjectOpResult ignored;
    return JS_DeleteElement(cx, obj, index, ignored);
}

JS_PUBLIC_API(bool)
JS_Enumerate(JSContext* cx, HandleObject obj, JS::MutableHandle<IdVector> props)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj, props);
    MOZ_ASSERT(props.empty());

    AutoIdVector ids(cx);
    if (!GetPropertyKeys(cx, obj, JSITER_OWNONLY, &ids)) {
        return false;
    }

    return props.append(ids.begin(), ids.end());
}

JS_PUBLIC_API(bool)
JS::IsCallable(JSObject* obj)
{
    return obj->isCallable();
}

JS_PUBLIC_API(bool)
JS::IsConstructor(JSObject* obj)
{
    return obj->isConstructor();
}

JS_PUBLIC_API(bool)
JS_CallFunctionValue(JSContext* cx, HandleObject obj, HandleValue fval, const HandleValueArray& args,
                     MutableHandleValue rval)
{
    MOZ_ASSERT(!cx->zone()->isAtomsZone());
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj, fval, args);

    InvokeArgs iargs(cx);
    if (!FillArgumentsFromArraylike(cx, iargs, args)) {
        return false;
    }

    RootedValue thisv(cx, ObjectOrNullValue(obj));
    return Call(cx, fval, thisv, iargs, rval);
}

JS_PUBLIC_API(bool)
JS_CallFunction(JSContext* cx, HandleObject obj, HandleFunction fun, const HandleValueArray& args,
                MutableHandleValue rval)
{
    MOZ_ASSERT(!cx->zone()->isAtomsZone());
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj, fun, args);

    InvokeArgs iargs(cx);
    if (!FillArgumentsFromArraylike(cx, iargs, args)) {
        return false;
    }

    RootedValue fval(cx, ObjectValue(*fun));
    RootedValue thisv(cx, ObjectOrNullValue(obj));
    return Call(cx, fval, thisv, iargs, rval);
}

JS_PUBLIC_API(bool)
JS_CallFunctionName(JSContext* cx, HandleObject obj, const char* name, const HandleValueArray& args,
                    MutableHandleValue rval)
{
    MOZ_ASSERT(!cx->zone()->isAtomsZone());
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj, args);

    JSAtom* atom = Atomize(cx, name, strlen(name));
    if (!atom) {
        return false;
    }

    RootedValue fval(cx);
    RootedId id(cx, AtomToId(atom));
    if (!GetProperty(cx, obj, obj, id, &fval)) {
        return false;
    }

    InvokeArgs iargs(cx);
    if (!FillArgumentsFromArraylike(cx, iargs, args)) {
        return false;
    }

    RootedValue thisv(cx, ObjectOrNullValue(obj));
    return Call(cx, fval, thisv, iargs, rval);
}

JS_PUBLIC_API(bool)
JS::Call(JSContext* cx, HandleValue thisv, HandleValue fval, const JS::HandleValueArray& args,
         MutableHandleValue rval)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(thisv, fval, args);

    InvokeArgs iargs(cx);
    if (!FillArgumentsFromArraylike(cx, iargs, args)) {
        return false;
    }

    return Call(cx, fval, thisv, iargs, rval);
}

JS_PUBLIC_API(bool)
JS::Construct(JSContext* cx, HandleValue fval, HandleObject newTarget, const JS::HandleValueArray& args,
              MutableHandleObject objp)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(fval, newTarget, args);

    if (!IsConstructor(fval)) {
        ReportValueError(cx, JSMSG_NOT_CONSTRUCTOR, JSDVG_IGNORE_STACK, fval, nullptr);
        return false;
    }

    RootedValue newTargetVal(cx, ObjectValue(*newTarget));
    if (!IsConstructor(newTargetVal)) {
        ReportValueError(cx, JSMSG_NOT_CONSTRUCTOR, JSDVG_IGNORE_STACK, newTargetVal, nullptr);
        return false;
    }

    ConstructArgs cargs(cx);
    if (!FillArgumentsFromArraylike(cx, cargs, args)) {
        return false;
    }

    return js::Construct(cx, fval, cargs, newTargetVal, objp);
}

JS_PUBLIC_API(bool)
JS::Construct(JSContext* cx, HandleValue fval, const JS::HandleValueArray& args,
              MutableHandleObject objp)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(fval, args);

    if (!IsConstructor(fval)) {
        ReportValueError(cx, JSMSG_NOT_CONSTRUCTOR, JSDVG_IGNORE_STACK, fval, nullptr);
        return false;
    }

    ConstructArgs cargs(cx);
    if (!FillArgumentsFromArraylike(cx, cargs, args)) {
        return false;
    }

    return js::Construct(cx, fval, cargs, fval, objp);
}


/* * */

JS_PUBLIC_API(bool)
JS_AlreadyHasOwnPropertyById(JSContext* cx, HandleObject obj, HandleId id, bool* foundp)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj, id);

    if (!obj->isNative()) {
        return js::HasOwnProperty(cx, obj, id, foundp);
    }

    RootedNativeObject nativeObj(cx, &obj->as<NativeObject>());
    Rooted<PropertyResult> prop(cx);
    NativeLookupOwnPropertyNoResolve(cx, nativeObj, id, &prop);
    *foundp = prop.isFound();
    return true;
}

JS_PUBLIC_API(bool)
JS_AlreadyHasOwnProperty(JSContext* cx, HandleObject obj, const char* name, bool* foundp)
{
    JSAtom* atom = Atomize(cx, name, strlen(name));
    if (!atom) {
        return false;
    }
    RootedId id(cx, AtomToId(atom));
    return JS_AlreadyHasOwnPropertyById(cx, obj, id, foundp);
}

JS_PUBLIC_API(bool)
JS_AlreadyHasOwnUCProperty(JSContext* cx, HandleObject obj, const char16_t* name, size_t namelen,
                           bool* foundp)
{
    JSAtom* atom = AtomizeChars(cx, name, AUTO_NAMELEN(name, namelen));
    if (!atom) {
        return false;
    }
    RootedId id(cx, AtomToId(atom));
    return JS_AlreadyHasOwnPropertyById(cx, obj, id, foundp);
}

JS_PUBLIC_API(bool)
JS_AlreadyHasOwnElement(JSContext* cx, HandleObject obj, uint32_t index, bool* foundp)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    RootedId id(cx);
    if (!IndexToId(cx, index, &id)) {
        return false;
    }
    return JS_AlreadyHasOwnPropertyById(cx, obj, id, foundp);
}

JS_PUBLIC_API(bool)
JS_FreezeObject(JSContext* cx, HandleObject obj)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj);
    return FreezeObject(cx, obj);
}

static bool
DeepFreezeSlot(JSContext* cx, const Value& v)
{
    if (v.isPrimitive()) {
        return true;
    }
    RootedObject obj(cx, &v.toObject());
    return JS_DeepFreezeObject(cx, obj);
}

JS_PUBLIC_API(bool)
JS_DeepFreezeObject(JSContext* cx, HandleObject obj)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj);

    /* Assume that non-extensible objects are already deep-frozen, to avoid divergence. */
    bool extensible;
    if (!IsExtensible(cx, obj, &extensible)) {
        return false;
    }
    if (!extensible) {
        return true;
    }

    if (!FreezeObject(cx, obj)) {
        return false;
    }

    /* Walk slots in obj and if any value is a non-null object, seal it. */
    if (obj->isNative()) {
        RootedNativeObject nobj(cx, &obj->as<NativeObject>());
        for (uint32_t i = 0, n = nobj->slotSpan(); i < n; ++i) {
            if (!DeepFreezeSlot(cx, nobj->getSlot(i))) {
                return false;
            }
        }
        for (uint32_t i = 0, n = nobj->getDenseInitializedLength(); i < n; ++i) {
            if (!DeepFreezeSlot(cx, nobj->getDenseElement(i))) {
                return false;
            }
        }
    }

    return true;
}

static bool
DefineSelfHostedProperty(JSContext* cx, HandleObject obj, HandleId id,
                         const char* getterName, const char* setterName,
                         unsigned attrs)
{
    JSAtom* getterNameAtom = Atomize(cx, getterName, strlen(getterName));
    if (!getterNameAtom) {
        return false;
    }
    RootedPropertyName getterNameName(cx, getterNameAtom->asPropertyName());

    RootedAtom name(cx, IdToFunctionName(cx, id));
    if (!name) {
        return false;
    }

    RootedValue getterValue(cx);
    if (!GlobalObject::getSelfHostedFunction(cx, cx->global(), getterNameName, name, 0,
                                             &getterValue))
    {
        return false;
    }
    MOZ_ASSERT(getterValue.isObject() && getterValue.toObject().is<JSFunction>());
    RootedFunction getterFunc(cx, &getterValue.toObject().as<JSFunction>());

    RootedFunction setterFunc(cx);
    if (setterName) {
        JSAtom* setterNameAtom = Atomize(cx, setterName, strlen(setterName));
        if (!setterNameAtom) {
            return false;
        }
        RootedPropertyName setterNameName(cx, setterNameAtom->asPropertyName());

        RootedValue setterValue(cx);
        if (!GlobalObject::getSelfHostedFunction(cx, cx->global(), setterNameName, name, 0,
                                                 &setterValue))
        {
            return false;
        }
        MOZ_ASSERT(setterValue.isObject() && setterValue.toObject().is<JSFunction>());
        setterFunc = &setterValue.toObject().as<JSFunction>();
    }

    return DefineAccessorPropertyById(cx, obj, id, getterFunc, setterFunc, attrs);
}

JS_PUBLIC_API(JSObject*)
JS_DefineObject(JSContext* cx, HandleObject obj, const char* name, const JSClass* jsclasp,
                unsigned attrs)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj);

    const Class* clasp = Valueify(jsclasp);
    if (!clasp) {
        clasp = &PlainObject::class_;    /* default class is Object */
    }

    RootedObject nobj(cx, NewBuiltinClassInstance(cx, clasp));
    if (!nobj) {
        return nullptr;
    }

    RootedValue nobjValue(cx, ObjectValue(*nobj));
    if (!DefineDataProperty(cx, obj, name, nobjValue, attrs)) {
        return nullptr;
    }

    return nobj;
}

static inline Value
ValueFromScalar(double x)
{
    return DoubleValue(x);
}
static inline Value
ValueFromScalar(int32_t x)
{
    return Int32Value(x);
}

template<typename T>
static bool
DefineConstScalar(JSContext* cx, HandleObject obj, const JSConstScalarSpec<T>* cds)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    unsigned attrs = JSPROP_READONLY | JSPROP_PERMANENT;
    for (; cds->name; cds++) {
        RootedValue value(cx, ValueFromScalar(cds->val));
        if (!DefineDataProperty(cx, obj, cds->name, value, attrs)) {
            return false;
        }
    }
    return true;
}

JS_PUBLIC_API(bool)
JS_DefineConstDoubles(JSContext* cx, HandleObject obj, const JSConstDoubleSpec* cds)
{
    return DefineConstScalar(cx, obj, cds);
}
JS_PUBLIC_API(bool)
JS_DefineConstIntegers(JSContext* cx, HandleObject obj, const JSConstIntegerSpec* cis)
{
    return DefineConstScalar(cx, obj, cis);
}

JS_PUBLIC_API(bool)
JSPropertySpec::getValue(JSContext* cx, MutableHandleValue vp) const
{
    MOZ_ASSERT(!isAccessor());

    if (value.type == JSVAL_TYPE_STRING) {
        RootedAtom atom(cx, Atomize(cx, value.string, strlen(value.string)));
        if (!atom) {
            return false;
        }
        vp.setString(atom);
    } else {
        MOZ_ASSERT(value.type == JSVAL_TYPE_INT32);
        vp.setInt32(value.int32);
    }

    return true;
}

static JS::SymbolCode
PropertySpecNameToSymbolCode(const char* name)
{
    MOZ_ASSERT(JS::PropertySpecNameIsSymbol(name));
    uintptr_t u = reinterpret_cast<uintptr_t>(name);
    return JS::SymbolCode(u - 1);
}

bool
PropertySpecNameToId(JSContext* cx, const char* name, MutableHandleId id,
                     js::PinningBehavior pin = js::DoNotPinAtom)
{
    if (JS::PropertySpecNameIsSymbol(name)) {
        JS::SymbolCode which = PropertySpecNameToSymbolCode(name);
        id.set(SYMBOL_TO_JSID(cx->wellKnownSymbols().get(which)));
    } else {
        JSAtom* atom = Atomize(cx, name, strlen(name), pin);
        if (!atom) {
            return false;
        }
        id.set(AtomToId(atom));
    }
    return true;
}

JS_PUBLIC_API(bool)
JS::PropertySpecNameToPermanentId(JSContext* cx, const char* name, jsid* idp)
{
    // We are calling fromMarkedLocation(idp) even though idp points to a
    // location that will never be marked. This is OK because the whole point
    // of this API is to populate *idp with a jsid that does not need to be
    // marked.
    return PropertySpecNameToId(cx, name, MutableHandleId::fromMarkedLocation(idp),
                                js::PinAtom);
}

JS_PUBLIC_API(bool)
JS_DefineProperties(JSContext* cx, HandleObject obj, const JSPropertySpec* ps)
{
    RootedId id(cx);

    for (; ps->name; ps++) {
        if (!PropertySpecNameToId(cx, ps->name, &id)) {
            return false;
        }

        if (ps->isAccessor()) {
            if (ps->isSelfHosted()) {
                if (!DefineSelfHostedProperty(cx, obj, id,
                                              ps->accessors.getter.selfHosted.funname,
                                              ps->accessors.setter.selfHosted.funname,
                                              ps->flags))
                {
                    return false;
                }
            } else {
                if (!DefineAccessorPropertyById(cx, obj, id,
                                                ps->accessors.getter.native,
                                                ps->accessors.setter.native,
                                                ps->flags))
                {
                    return false;
                }
            }
        } else {
            RootedValue v(cx);
            if (!ps->getValue(cx, &v)) {
                return false;
            }

            if (!DefineDataPropertyById(cx, obj, id, v, ps->flags & ~JSPROP_INTERNAL_USE_BIT)) {
                return false;
            }
        }
    }
    return true;
}

JS_PUBLIC_API(bool)
JS::ObjectToCompletePropertyDescriptor(JSContext* cx,
                                       HandleObject obj,
                                       HandleValue descObj,
                                       MutableHandle<PropertyDescriptor> desc)
{
    // |obj| can be in a different compartment here. The caller is responsible
    // for wrapping it (see JS_WrapPropertyDescriptor).
    cx->check(descObj);
    if (!ToPropertyDescriptor(cx, descObj, true, desc)) {
        return false;
    }
    CompletePropertyDescriptor(desc);
    desc.object().set(obj);
    return true;
}

JS_PUBLIC_API(void)
JS_SetAllNonReservedSlotsToUndefined(JSContext* cx, JSObject* objArg)
{
    RootedObject obj(cx, objArg);
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj);

    if (!obj->isNative()) {
        return;
    }

    const Class* clasp = obj->getClass();
    unsigned numReserved = JSCLASS_RESERVED_SLOTS(clasp);
    unsigned numSlots = obj->as<NativeObject>().slotSpan();
    for (unsigned i = numReserved; i < numSlots; i++) {
        obj->as<NativeObject>().setSlot(i, UndefinedValue());
    }
}

JS_PUBLIC_API(Value)
JS_GetReservedSlot(JSObject* obj, uint32_t index)
{
    return obj->as<NativeObject>().getReservedSlot(index);
}

JS_PUBLIC_API(void)
JS_SetReservedSlot(JSObject* obj, uint32_t index, const Value& value)
{
    obj->as<NativeObject>().setReservedSlot(index, value);
}

JS_PUBLIC_API(JSObject*)
JS_NewArrayObject(JSContext* cx, const JS::HandleValueArray& contents)
{
    MOZ_ASSERT(!cx->zone()->isAtomsZone());
    AssertHeapIsIdle();
    CHECK_THREAD(cx);

    cx->check(contents);
    return NewDenseCopiedArray(cx, contents.length(), contents.begin());
}

JS_PUBLIC_API(JSObject*)
JS_NewArrayObject(JSContext* cx, size_t length)
{
    MOZ_ASSERT(!cx->zone()->isAtomsZone());
    AssertHeapIsIdle();
    CHECK_THREAD(cx);

    return NewDenseFullyAllocatedArray(cx, length);
}

inline bool
IsGivenTypeObject(JSContext* cx, JS::HandleObject obj, const ESClass& typeClass, bool* isType)
{
    cx->check(obj);

    ESClass cls;
    if (!GetBuiltinClass(cx, obj, &cls)) {
        return false;
    }

    *isType = cls == typeClass;
    return true;
}

JS_PUBLIC_API(bool)
JS_IsArrayObject(JSContext* cx, JS::HandleObject obj, bool* isArray)
{
    return IsGivenTypeObject(cx, obj, ESClass::Array, isArray);
}

JS_PUBLIC_API(bool)
JS_IsArrayObject(JSContext* cx, JS::HandleValue value, bool* isArray)
{
    if (!value.isObject()) {
        *isArray = false;
        return true;
    }

    RootedObject obj(cx, &value.toObject());
    return JS_IsArrayObject(cx, obj, isArray);
}

JS_PUBLIC_API(bool)
JS_GetArrayLength(JSContext* cx, HandleObject obj, uint32_t* lengthp)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj);
    return GetLengthProperty(cx, obj, lengthp);
}

JS_PUBLIC_API(bool)
JS_SetArrayLength(JSContext* cx, HandleObject obj, uint32_t length)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj);
    return SetLengthProperty(cx, obj, length);
}

JS_PUBLIC_API(bool)
JS::IsMapObject(JSContext* cx, JS::HandleObject obj, bool* isMap)
{
    return IsGivenTypeObject(cx, obj, ESClass::Map, isMap);
}

JS_PUBLIC_API(bool)
JS::IsSetObject(JSContext* cx, JS::HandleObject obj, bool* isSet)
{
    return IsGivenTypeObject(cx, obj, ESClass::Set, isSet);
}

JS_PUBLIC_API(void)
JS_HoldPrincipals(JSPrincipals* principals)
{
    ++principals->refcount;
}

JS_PUBLIC_API(void)
JS_DropPrincipals(JSContext* cx, JSPrincipals* principals)
{
    int rc = --principals->refcount;
    if (rc == 0) {
        JS::AutoSuppressGCAnalysis nogc;
        cx->runtime()->destroyPrincipals(principals);
    }
}

JS_PUBLIC_API(void)
JS_SetSecurityCallbacks(JSContext* cx, const JSSecurityCallbacks* scb)
{
    MOZ_ASSERT(scb != &NullSecurityCallbacks);
    cx->runtime()->securityCallbacks = scb ? scb : &NullSecurityCallbacks;
}

JS_PUBLIC_API(const JSSecurityCallbacks*)
JS_GetSecurityCallbacks(JSContext* cx)
{
    return (cx->runtime()->securityCallbacks != &NullSecurityCallbacks)
           ? cx->runtime()->securityCallbacks.ref()
           : nullptr;
}

JS_PUBLIC_API(void)
JS_SetTrustedPrincipals(JSContext* cx, JSPrincipals* prin)
{
    cx->runtime()->setTrustedPrincipals(prin);
}

extern JS_PUBLIC_API(void)
JS_InitDestroyPrincipalsCallback(JSContext* cx, JSDestroyPrincipalsOp destroyPrincipals)
{
    MOZ_ASSERT(destroyPrincipals);
    MOZ_ASSERT(!cx->runtime()->destroyPrincipals);
    cx->runtime()->destroyPrincipals = destroyPrincipals;
}

extern JS_PUBLIC_API(void)
JS_InitReadPrincipalsCallback(JSContext* cx, JSReadPrincipalsOp read)
{
    MOZ_ASSERT(read);
    MOZ_ASSERT(!cx->runtime()->readPrincipals);
    cx->runtime()->readPrincipals = read;
}

JS_PUBLIC_API(JSFunction*)
JS_NewFunction(JSContext* cx, JSNative native, unsigned nargs, unsigned flags,
               const char* name)
{
    MOZ_ASSERT(!cx->zone()->isAtomsZone());

    AssertHeapIsIdle();
    CHECK_THREAD(cx);

    RootedAtom atom(cx);
    if (name) {
        atom = Atomize(cx, name, strlen(name));
        if (!atom) {
            return nullptr;
        }
    }

    return (flags & JSFUN_CONSTRUCTOR)
           ? NewNativeConstructor(cx, native, nargs, atom)
           : NewNativeFunction(cx, native, nargs, atom);
}

JS_PUBLIC_API(JSFunction*)
JS::GetSelfHostedFunction(JSContext* cx, const char* selfHostedName, HandleId id, unsigned nargs)
{
    MOZ_ASSERT(!cx->zone()->isAtomsZone());
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(id);

    RootedAtom name(cx, IdToFunctionName(cx, id));
    if (!name) {
        return nullptr;
    }

    JSAtom* shAtom = Atomize(cx, selfHostedName, strlen(selfHostedName));
    if (!shAtom) {
        return nullptr;
    }
    RootedPropertyName shName(cx, shAtom->asPropertyName());
    RootedValue funVal(cx);
    if (!GlobalObject::getSelfHostedFunction(cx, cx->global(), shName, name, nargs, &funVal)) {
        return nullptr;
    }
    return &funVal.toObject().as<JSFunction>();
}

JS_PUBLIC_API(JSFunction*)
JS::NewFunctionFromSpec(JSContext* cx, const JSFunctionSpec* fs, HandleId id)
{
    cx->check(id);

    // Delay cloning self-hosted functions until they are called. This is
    // achieved by passing DefineFunction a nullptr JSNative which produces an
    // interpreted JSFunction where !hasScript. Interpreted call paths then
    // call InitializeLazyFunctionScript if !hasScript.
    if (fs->selfHostedName) {
        MOZ_ASSERT(!fs->call.op);
        MOZ_ASSERT(!fs->call.info);

        JSAtom* shAtom = Atomize(cx, fs->selfHostedName, strlen(fs->selfHostedName));
        if (!shAtom) {
            return nullptr;
        }
        RootedPropertyName shName(cx, shAtom->asPropertyName());
        RootedAtom name(cx, IdToFunctionName(cx, id));
        if (!name) {
            return nullptr;
        }
        RootedValue funVal(cx);
        if (!GlobalObject::getSelfHostedFunction(cx, cx->global(), shName, name, fs->nargs,
                                                 &funVal))
        {
            return nullptr;
        }
        return &funVal.toObject().as<JSFunction>();
    }

    RootedAtom atom(cx, IdToFunctionName(cx, id));
    if (!atom) {
        return nullptr;
    }

    JSFunction* fun;
    if (!fs->call.op) {
        fun = NewScriptedFunction(cx, fs->nargs, JSFunction::INTERPRETED_LAZY, atom);
    } else if (fs->flags & JSFUN_CONSTRUCTOR) {
        fun = NewNativeConstructor(cx, fs->call.op, fs->nargs, atom);
    } else {
        fun = NewNativeFunction(cx, fs->call.op, fs->nargs, atom);
    }
    if (!fun) {
        return nullptr;
    }

    if (fs->call.info) {
        fun->setJitInfo(fs->call.info);
    }
    return fun;
}

static bool
IsFunctionCloneable(HandleFunction fun)
{
    // If a function was compiled with non-global syntactic environments on
    // the environment chain, we could have baked in EnvironmentCoordinates
    // into the script. We cannot clone it without breaking the compiler's
    // assumptions.
    for (ScopeIter si(fun->nonLazyScript()->enclosingScope()); si; si++) {
        if (si.scope()->is<GlobalScope>()) {
            return true;
        }
        if (si.hasSyntacticEnvironment()) {
            return false;
        }
    }

    return true;
}

static JSObject*
CloneFunctionObject(JSContext* cx, HandleObject funobj, HandleObject env, HandleScope scope)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(env);
    MOZ_ASSERT(env);
    // Note that funobj can be in a different compartment.

    if (!funobj->is<JSFunction>()) {
        MOZ_RELEASE_ASSERT(!IsCrossCompartmentWrapper(funobj));
        AutoRealm ar(cx, funobj);
        RootedValue v(cx, ObjectValue(*funobj));
        ReportIsNotFunction(cx, v);
        return nullptr;
    }

    RootedFunction fun(cx, &funobj->as<JSFunction>());
    if (fun->isInterpretedLazy()) {
        AutoRealm ar(cx, fun);
        if (!JSFunction::getOrCreateScript(cx, fun)) {
            return nullptr;
        }
    }

    // Only allow cloning normal, interpreted functions.
    if (fun->isNative() ||
        fun->isBoundFunction() ||
        fun->kind() != JSFunction::NormalFunction ||
        fun->isExtended())
    {
        JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_CANT_CLONE_OBJECT);
        return nullptr;
    }

    if (!IsFunctionCloneable(fun)) {
        JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_BAD_CLONE_FUNOBJ_SCOPE);
        return nullptr;
    }

    if (CanReuseScriptForClone(cx->realm(), fun, env)) {
        // If the script is to be reused, either the script can already handle
        // non-syntactic scopes, or there is only the standard global lexical
        // scope.
#ifdef DEBUG
        // Fail here if we OOM during debug asserting.
        // CloneFunctionReuseScript will delazify the script anyways, so we
        // are not creating an extra failure condition for DEBUG builds.
        if (!JSFunction::getOrCreateScript(cx, fun)) {
            return nullptr;
        }
        MOZ_ASSERT(scope->as<GlobalScope>().isSyntactic() ||
                   fun->nonLazyScript()->hasNonSyntacticScope());
#endif
        return CloneFunctionReuseScript(cx, fun, env, fun->getAllocKind());
    }

    JSFunction* clone = CloneFunctionAndScript(cx, fun, env, scope, fun->getAllocKind());

#ifdef DEBUG
    // The cloned function should itself be cloneable.
    RootedFunction cloneRoot(cx, clone);
    MOZ_ASSERT_IF(cloneRoot, IsFunctionCloneable(cloneRoot));
#endif

    return clone;
}

JS_PUBLIC_API(JSObject*)
JS::CloneFunctionObject(JSContext* cx, HandleObject funobj)
{
    RootedObject globalLexical(cx, &cx->global()->lexicalEnvironment());
    RootedScope emptyGlobalScope(cx, &cx->global()->emptyGlobalScope());
    return CloneFunctionObject(cx, funobj, globalLexical, emptyGlobalScope);
}

extern JS_PUBLIC_API(JSObject*)
JS::CloneFunctionObject(JSContext* cx, HandleObject funobj, AutoObjectVector& envChain)
{
    RootedObject env(cx);
    RootedScope scope(cx);
    if (!CreateNonSyntacticEnvironmentChain(cx, envChain, &env, &scope)) {
        return nullptr;
    }
    return CloneFunctionObject(cx, funobj, env, scope);
}

JS_PUBLIC_API(JSObject*)
JS_GetFunctionObject(JSFunction* fun)
{
    return fun;
}

JS_PUBLIC_API(JSString*)
JS_GetFunctionId(JSFunction* fun)
{
    return fun->explicitName();
}

JS_PUBLIC_API(JSString*)
JS_GetFunctionDisplayId(JSFunction* fun)
{
    return fun->displayAtom();
}

JS_PUBLIC_API(uint16_t)
JS_GetFunctionArity(JSFunction* fun)
{
    return fun->nargs();
}

JS_PUBLIC_API(bool)
JS_GetFunctionLength(JSContext* cx, HandleFunction fun, uint16_t* length)
{
    cx->check(fun);
    return JSFunction::getLength(cx, fun, length);
}

JS_PUBLIC_API(bool)
JS_ObjectIsFunction(JSContext* cx, JSObject* obj)
{
    return obj->is<JSFunction>();
}

JS_PUBLIC_API(bool)
JS_IsNativeFunction(JSObject* funobj, JSNative call)
{
    if (!funobj->is<JSFunction>()) {
        return false;
    }
    JSFunction* fun = &funobj->as<JSFunction>();
    return fun->isNative() && fun->native() == call;
}

extern JS_PUBLIC_API(bool)
JS_IsConstructor(JSFunction* fun)
{
    return fun->isConstructor();
}

JS_PUBLIC_API(bool)
JS_DefineFunctions(JSContext* cx, HandleObject obj, const JSFunctionSpec* fs)
{
    MOZ_ASSERT(!cx->zone()->isAtomsZone());
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj);

    return DefineFunctions(cx, obj, fs, NotIntrinsic);
}

JS_PUBLIC_API(JSFunction*)
JS_DefineFunction(JSContext* cx, HandleObject obj, const char* name, JSNative call,
                  unsigned nargs, unsigned attrs)
{
    MOZ_ASSERT(!cx->zone()->isAtomsZone());
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj);
    JSAtom* atom = Atomize(cx, name, strlen(name));
    if (!atom) {
        return nullptr;
    }
    Rooted<jsid> id(cx, AtomToId(atom));
    return DefineFunction(cx, obj, id, call, nargs, attrs);
}

JS_PUBLIC_API(JSFunction*)
JS_DefineUCFunction(JSContext* cx, HandleObject obj,
                    const char16_t* name, size_t namelen, JSNative call,
                    unsigned nargs, unsigned attrs)
{
    MOZ_ASSERT(!cx->zone()->isAtomsZone());
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj);
    JSAtom* atom = AtomizeChars(cx, name, AUTO_NAMELEN(name, namelen));
    if (!atom) {
        return nullptr;
    }
    Rooted<jsid> id(cx, AtomToId(atom));
    return DefineFunction(cx, obj, id, call, nargs, attrs);
}

extern JS_PUBLIC_API(JSFunction*)
JS_DefineFunctionById(JSContext* cx, HandleObject obj, HandleId id, JSNative call,
                      unsigned nargs, unsigned attrs)
{
    MOZ_ASSERT(!cx->zone()->isAtomsZone());
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(obj, id);
    return DefineFunction(cx, obj, id, call, nargs, attrs);
}

void
JS::TransitiveCompileOptions::copyPODTransitiveOptions(const TransitiveCompileOptions& rhs)
{
    mutedErrors_ = rhs.mutedErrors_;
    selfHostingMode = rhs.selfHostingMode;
    canLazilyParse = rhs.canLazilyParse;
    strictOption = rhs.strictOption;
    extraWarningsOption = rhs.extraWarningsOption;
    werrorOption = rhs.werrorOption;
    asmJSOption = rhs.asmJSOption;
    throwOnAsmJSValidationFailureOption = rhs.throwOnAsmJSValidationFailureOption;
    forceAsync = rhs.forceAsync;
    sourceIsLazy = rhs.sourceIsLazy;
    introductionType = rhs.introductionType;
    introductionLineno = rhs.introductionLineno;
    introductionOffset = rhs.introductionOffset;
    hasIntroductionInfo = rhs.hasIntroductionInfo;
    isProbablySystemCode = rhs.isProbablySystemCode;
    hideScriptFromDebugger = rhs.hideScriptFromDebugger;
};

void
JS::ReadOnlyCompileOptions::copyPODOptions(const ReadOnlyCompileOptions& rhs)
{
    copyPODTransitiveOptions(rhs);
    lineno = rhs.lineno;
    column = rhs.column;
    scriptSourceOffset = rhs.scriptSourceOffset;
    isRunOnce = rhs.isRunOnce;
    noScriptRval = rhs.noScriptRval;
    nonSyntacticScope = rhs.nonSyntacticScope;
}

JS::OwningCompileOptions::OwningCompileOptions(JSContext* cx)
    : ReadOnlyCompileOptions(),
      elementRoot(cx),
      elementAttributeNameRoot(cx),
      introductionScriptRoot(cx)
{
}

JS::OwningCompileOptions::~OwningCompileOptions()
{
    // OwningCompileOptions always owns these, so these casts are okay.
    js_free(const_cast<char*>(filename_));
    js_free(const_cast<char16_t*>(sourceMapURL_));
    js_free(const_cast<char*>(introducerFilename_));
}

size_t
JS::OwningCompileOptions::sizeOfExcludingThis(mozilla::MallocSizeOf mallocSizeOf) const
{
    return mallocSizeOf(filename_) +
           mallocSizeOf(sourceMapURL_) +
           mallocSizeOf(introducerFilename_);
}

bool
JS::OwningCompileOptions::copy(JSContext* cx, const ReadOnlyCompileOptions& rhs)
{
    copyPODOptions(rhs);

    setElement(rhs.element());
    setElementAttributeName(rhs.elementAttributeName());
    setIntroductionScript(rhs.introductionScript());

    return setFileAndLine(cx, rhs.filename(), rhs.lineno) &&
           setSourceMapURL(cx, rhs.sourceMapURL()) &&
           setIntroducerFilename(cx, rhs.introducerFilename());
}

bool
JS::OwningCompileOptions::setFile(JSContext* cx, const char* f)
{
    char* copy = nullptr;
    if (f) {
        copy = DuplicateString(cx, f).release();
        if (!copy) {
            return false;
        }
    }

    // OwningCompileOptions always owns filename_, so this cast is okay.
    js_free(const_cast<char*>(filename_));

    filename_ = copy;
    return true;
}

bool
JS::OwningCompileOptions::setFileAndLine(JSContext* cx, const char* f, unsigned l)
{
    if (!setFile(cx, f)) {
        return false;
    }

    lineno = l;
    return true;
}

bool
JS::OwningCompileOptions::setSourceMapURL(JSContext* cx, const char16_t* s)
{
    UniqueTwoByteChars copy;
    if (s) {
        copy = DuplicateString(cx, s);
        if (!copy) {
            return false;
        }
    }

    // OwningCompileOptions always owns sourceMapURL_, so this cast is okay.
    js_free(const_cast<char16_t*>(sourceMapURL_));

    sourceMapURL_ = copy.release();
    return true;
}

bool
JS::OwningCompileOptions::setIntroducerFilename(JSContext* cx, const char* s)
{
    char* copy = nullptr;
    if (s) {
        copy = DuplicateString(cx, s).release();
        if (!copy) {
            return false;
        }
    }

    // OwningCompileOptions always owns introducerFilename_, so this cast is okay.
    js_free(const_cast<char*>(introducerFilename_));

    introducerFilename_ = copy;
    return true;
}

JS::CompileOptions::CompileOptions(JSContext* cx)
    : ReadOnlyCompileOptions(), elementRoot(cx), elementAttributeNameRoot(cx),
      introductionScriptRoot(cx)
{
    strictOption = cx->options().strictMode();
    extraWarningsOption = cx->realm()->behaviors().extraWarnings(cx);
    isProbablySystemCode = cx->realm()->isProbablySystemCode();
    werrorOption = cx->options().werror();
    if (!cx->options().asmJS()) {
        asmJSOption = AsmJSOption::Disabled;
    } else if (cx->realm()->debuggerObservesAsmJS()) {
        asmJSOption = AsmJSOption::DisabledByDebugger;
    } else {
        asmJSOption = AsmJSOption::Enabled;
    }
    throwOnAsmJSValidationFailureOption = cx->options().throwOnAsmJSValidationFailure();
}

#if defined(JS_BUILD_BINAST)

JSScript*
JS::DecodeBinAST(JSContext* cx, const ReadOnlyCompileOptions& options,
                 const uint8_t* buf, size_t length)
{
    MOZ_ASSERT(!cx->zone()->isAtomsZone());
    AssertHeapIsIdle();
    CHECK_THREAD(cx);

    return frontend::CompileGlobalBinASTScript(cx, cx->tempLifoAlloc(), options, buf, length);
}

JSScript*
JS::DecodeBinAST(JSContext* cx, const ReadOnlyCompileOptions& options, FILE* file)
{
    FileContents fileContents(cx);
    if (!ReadCompleteFile(cx, file, fileContents)) {
        return nullptr;
    }

    return DecodeBinAST(cx, options, fileContents.begin(), fileContents.length());
}

JS_PUBLIC_API(bool)
JS::DecodeBinASTOffThread(JSContext* cx, const ReadOnlyCompileOptions& options,
                          const uint8_t* buf, size_t length,
                          OffThreadCompileCallback callback, void* callbackData)
{
    return StartOffThreadDecodeBinAST(cx, options, buf, length, callback, callbackData);
}

JS_PUBLIC_API(JSScript*)
JS::FinishOffThreadBinASTDecode(JSContext* cx, JS::OffThreadToken* token)
{
    MOZ_ASSERT(cx);
    MOZ_ASSERT(CurrentThreadCanAccessRuntime(cx->runtime()));
    return HelperThreadState().finishBinASTDecodeTask(cx, token);
}
#endif

JS_PUBLIC_API(JSObject*)
JS_GetGlobalFromScript(JSScript* script)
{
    MOZ_ASSERT(!script->isCachedEval());
    return &script->global();
}

JS_PUBLIC_API(const char*)
JS_GetScriptFilename(JSScript* script)
{
    // This is called from ThreadStackHelper which can be called from another
    // thread or inside a signal hander, so we need to be careful in case a
    // copmacting GC is currently moving things around.
    return script->maybeForwardedFilename();
}

JS_PUBLIC_API(unsigned)
JS_GetScriptBaseLineNumber(JSContext* cx, JSScript* script)
{
    return script->lineno();
}

JS_PUBLIC_API(JSScript*)
JS_GetFunctionScript(JSContext* cx, HandleFunction fun)
{
    if (fun->isNative()) {
        return nullptr;
    }
    if (fun->isInterpretedLazy()) {
        AutoRealm ar(cx, fun);
        JSScript* script = JSFunction::getOrCreateScript(cx, fun);
        if (!script) {
            MOZ_CRASH();
        }
        return script;
    }
    return fun->nonLazyScript();
}

JS_PUBLIC_API(JSString*)
JS_DecompileScript(JSContext* cx, HandleScript script)
{
    MOZ_ASSERT(!cx->zone()->isAtomsZone());

    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    script->ensureNonLazyCanonicalFunction();
    RootedFunction fun(cx, script->functionNonDelazifying());
    if (fun) {
        return JS_DecompileFunction(cx, fun);
    }
    bool haveSource = script->scriptSource()->hasSourceText();
    if (!haveSource && !JSScript::loadSource(cx, script->scriptSource(), &haveSource)) {
        return nullptr;
    }
    return haveSource ? JSScript::sourceData(cx, script)
                      : NewStringCopyZ<CanGC>(cx, "[no source]");
}

JS_PUBLIC_API(JSString*)
JS_DecompileFunction(JSContext* cx, HandleFunction fun)
{
    MOZ_ASSERT(!cx->zone()->isAtomsZone());
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(fun);
    return FunctionToString(cx, fun, /* isToSource = */ false);
}

JS_PUBLIC_API(JS::ModuleResolveHook)
JS::GetModuleResolveHook(JSRuntime* rt)
{
    AssertHeapIsIdle();
    return rt->moduleResolveHook;
}

JS_PUBLIC_API(void)
JS::SetModuleResolveHook(JSRuntime* rt, JS::ModuleResolveHook func)
{
    AssertHeapIsIdle();
    rt->moduleResolveHook = func;
}

JS_PUBLIC_API(JS::ModuleMetadataHook)
JS::GetModuleMetadataHook(JSRuntime* rt)
{
    AssertHeapIsIdle();
    return rt->moduleMetadataHook;
}

JS_PUBLIC_API(void)
JS::SetModuleMetadataHook(JSRuntime* rt, JS::ModuleMetadataHook func)
{
    AssertHeapIsIdle();
    rt->moduleMetadataHook = func;
}

JS_PUBLIC_API(JS::ModuleDynamicImportHook)
JS::GetModuleDynamicImportHook(JSRuntime* rt)
{
    AssertHeapIsIdle();
    return rt->moduleDynamicImportHook;
}

JS_PUBLIC_API(void)
JS::SetModuleDynamicImportHook(JSRuntime* rt, JS::ModuleDynamicImportHook func)
{
    AssertHeapIsIdle();
    rt->moduleDynamicImportHook = func;
}

JS_PUBLIC_API(bool)
JS::FinishDynamicModuleImport(JSContext* cx, HandleValue referencingPrivate, HandleString specifier,
                              HandleObject promise)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(referencingPrivate, promise);

    return js::FinishDynamicModuleImport(cx, referencingPrivate, specifier, promise);
}

JS_PUBLIC_API(bool)
JS::CompileModule(JSContext* cx, const ReadOnlyCompileOptions& options,
                  SourceText<char16_t>& srcBuf, JS::MutableHandleObject module)
{
    MOZ_ASSERT(!cx->zone()->isAtomsZone());
    AssertHeapIsIdle();
    CHECK_THREAD(cx);

    module.set(frontend::CompileModule(cx, options, srcBuf));
    return !!module;
}

JS_PUBLIC_API(void)
JS::SetModulePrivate(JSObject* module, const JS::Value& value)
{
    module->as<ModuleObject>().scriptSourceObject()->setPrivate(value);
}

JS_PUBLIC_API(JS::Value)
JS::GetModulePrivate(JSObject* module)
{
    return module->as<ModuleObject>().scriptSourceObject()->getPrivate();
}

JS_PUBLIC_API(void)
JS::SetScriptPrivate(JSScript* script, const JS::Value& value)
{
    script->scriptSourceUnwrap().setPrivate(value);
}

JS_PUBLIC_API(JS::Value)
JS::GetScriptPrivate(JSScript* script)
{
    return script->scriptSourceUnwrap().getPrivate();
}

JS_PUBLIC_API(bool)
JS::ModuleInstantiate(JSContext* cx, JS::HandleObject moduleArg)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(moduleArg);
    return ModuleObject::Instantiate(cx, moduleArg.as<ModuleObject>());
}

JS_PUBLIC_API(bool)
JS::ModuleEvaluate(JSContext* cx, JS::HandleObject moduleArg)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(moduleArg);
    return ModuleObject::Evaluate(cx, moduleArg.as<ModuleObject>());
}

JS_PUBLIC_API(JSObject*)
JS::GetRequestedModules(JSContext* cx, JS::HandleObject moduleArg)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(moduleArg);
    return &moduleArg->as<ModuleObject>().requestedModules();
}

JS_PUBLIC_API(JSString*)
JS::GetRequestedModuleSpecifier(JSContext* cx, JS::HandleValue value)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(value);
    JSObject* obj = &value.toObject();
    return obj->as<RequestedModuleObject>().moduleSpecifier();
}

JS_PUBLIC_API(void)
JS::GetRequestedModuleSourcePos(JSContext* cx, JS::HandleValue value,
                                uint32_t* lineNumber, uint32_t* columnNumber)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(value);
    MOZ_ASSERT(lineNumber);
    MOZ_ASSERT(columnNumber);
    auto& requested = value.toObject().as<RequestedModuleObject>();
    *lineNumber = requested.lineNumber();
    *columnNumber = requested.columnNumber();
}

JS_PUBLIC_API(JSScript*)
JS::GetModuleScript(JS::HandleObject moduleRecord)
{
    AssertHeapIsIdle();
    return moduleRecord->as<ModuleObject>().script();
}

JS_PUBLIC_API(JSObject*)
JS_New(JSContext* cx, HandleObject ctor, const JS::HandleValueArray& inputArgs)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(ctor, inputArgs);

    RootedValue ctorVal(cx, ObjectValue(*ctor));
    if (!IsConstructor(ctorVal)) {
        ReportValueError(cx, JSMSG_NOT_CONSTRUCTOR, JSDVG_IGNORE_STACK, ctorVal, nullptr);
        return nullptr;
    }

    ConstructArgs args(cx);
    if (!FillArgumentsFromArraylike(cx, args, inputArgs)) {
        return nullptr;
    }

    RootedObject obj(cx);
    if (!js::Construct(cx, ctorVal, args, ctorVal, &obj)) {
        return nullptr;
    }

    return obj;
}

JS_PUBLIC_API(bool)
JS_CheckForInterrupt(JSContext* cx)
{
    return js::CheckForInterrupt(cx);
}

JS_PUBLIC_API(bool)
JS_AddInterruptCallback(JSContext* cx, JSInterruptCallback callback)
{
    return cx->interruptCallbacks().append(callback);
}

JS_PUBLIC_API(bool)
JS_DisableInterruptCallback(JSContext* cx)
{
    bool result = cx->interruptCallbackDisabled;
    cx->interruptCallbackDisabled = true;
    return result;
}

JS_PUBLIC_API(void)
JS_ResetInterruptCallback(JSContext* cx, bool enable)
{
    cx->interruptCallbackDisabled = enable;
}

/************************************************************************/

/*
 * Promises.
 */
JS_PUBLIC_API(void)
JS::SetGetIncumbentGlobalCallback(JSContext* cx, JSGetIncumbentGlobalCallback callback)
{
    cx->getIncumbentGlobalCallback = callback;
}

JS_PUBLIC_API(void)
JS::SetEnqueuePromiseJobCallback(JSContext* cx, JSEnqueuePromiseJobCallback callback,
                                 void* data /* = nullptr */)
{
    cx->enqueuePromiseJobCallback = callback;
    cx->enqueuePromiseJobCallbackData = data;
}

extern JS_PUBLIC_API(void)
JS::SetPromiseRejectionTrackerCallback(JSContext* cx, JSPromiseRejectionTrackerCallback callback,
                                       void* data /* = nullptr */)
{
    cx->promiseRejectionTrackerCallback = callback;
    cx->promiseRejectionTrackerCallbackData = data;
}

extern JS_PUBLIC_API(void)
JS::JobQueueIsEmpty(JSContext* cx)
{
    cx->canSkipEnqueuingJobs = true;
}

extern JS_PUBLIC_API(void)
JS::JobQueueMayNotBeEmpty(JSContext* cx)
{
    cx->canSkipEnqueuingJobs = false;
}

JS_PUBLIC_API(JSObject*)
JS::NewPromiseObject(JSContext* cx, HandleObject executor, HandleObject proto /* = nullptr */)
{
    MOZ_ASSERT(!cx->zone()->isAtomsZone());
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(executor, proto);

    if (!executor) {
        return PromiseObject::createSkippingExecutor(cx);
    }

    MOZ_ASSERT(IsCallable(executor));
    return PromiseObject::create(cx, executor, proto);
}

JS_PUBLIC_API(bool)
JS::IsPromiseObject(JS::HandleObject obj)
{
    return obj->is<PromiseObject>();
}

JS_PUBLIC_API(JSObject*)
JS::GetPromiseConstructor(JSContext* cx)
{
    CHECK_THREAD(cx);
    Rooted<GlobalObject*> global(cx, cx->global());
    return GlobalObject::getOrCreatePromiseConstructor(cx, global);
}

JS_PUBLIC_API(JSObject*)
JS::GetPromisePrototype(JSContext* cx)
{
    CHECK_THREAD(cx);
    Rooted<GlobalObject*> global(cx, cx->global());
    return GlobalObject::getOrCreatePromisePrototype(cx, global);
}

JS_PUBLIC_API(JS::PromiseState)
JS::GetPromiseState(JS::HandleObject promiseObj_)
{
    JSObject* promiseObj = CheckedUnwrap(promiseObj_);
    if (!promiseObj || !promiseObj->is<PromiseObject>()) {
        return JS::PromiseState::Pending;
    }

    return promiseObj->as<PromiseObject>().state();
}

JS_PUBLIC_API(uint64_t)
JS::GetPromiseID(JS::HandleObject promise)
{
    return promise->as<PromiseObject>().getID();
}

JS_PUBLIC_API(JS::Value)
JS::GetPromiseResult(JS::HandleObject promiseObj)
{
    PromiseObject* promise = &promiseObj->as<PromiseObject>();
    MOZ_ASSERT(promise->state() != JS::PromiseState::Pending);
    return promise->state() == JS::PromiseState::Fulfilled ? promise->value() : promise->reason();
}

JS_PUBLIC_API(JSObject*)
JS::GetPromiseAllocationSite(JS::HandleObject promise)
{
    return promise->as<PromiseObject>().allocationSite();
}

JS_PUBLIC_API(JSObject*)
JS::GetPromiseResolutionSite(JS::HandleObject promise)
{
    return promise->as<PromiseObject>().resolutionSite();
}

#ifdef DEBUG
JS_PUBLIC_API(void)
JS::DumpPromiseAllocationSite(JSContext* cx, JS::HandleObject promise)
{
    RootedObject stack(cx, promise->as<PromiseObject>().allocationSite());
    JSPrincipals* principals = cx->realm()->principals();
    UniqueChars stackStr = BuildUTF8StackString(cx, principals, stack);
    if (stackStr) {
        fputs(stackStr.get(), stderr);
    }
}

JS_PUBLIC_API(void)
JS::DumpPromiseResolutionSite(JSContext* cx, JS::HandleObject promise)
{
    RootedObject stack(cx, promise->as<PromiseObject>().resolutionSite());
    JSPrincipals* principals = cx->realm()->principals();
    UniqueChars stackStr = BuildUTF8StackString(cx, principals, stack);
    if (stackStr) {
        fputs(stackStr.get(), stderr);
    }
}
#endif

JS_PUBLIC_API(JSObject*)
JS::CallOriginalPromiseResolve(JSContext* cx, JS::HandleValue resolutionValue)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(resolutionValue);

    RootedObject promise(cx, PromiseObject::unforgeableResolve(cx, resolutionValue));
    MOZ_ASSERT_IF(promise, CheckedUnwrap(promise)->is<PromiseObject>());
    return promise;
}

JS_PUBLIC_API(JSObject*)
JS::CallOriginalPromiseReject(JSContext* cx, JS::HandleValue rejectionValue)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(rejectionValue);

    RootedObject promise(cx, PromiseObject::unforgeableReject(cx, rejectionValue));
    MOZ_ASSERT_IF(promise, CheckedUnwrap(promise)->is<PromiseObject>());
    return promise;
}

static bool
ResolveOrRejectPromise(JSContext* cx, JS::HandleObject promiseObj, JS::HandleValue resultOrReason_,
                       bool reject)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(promiseObj, resultOrReason_);

    mozilla::Maybe<AutoRealm> ar;
    Rooted<PromiseObject*> promise(cx);
    RootedValue resultOrReason(cx, resultOrReason_);
    if (IsWrapper(promiseObj)) {
        JSObject* unwrappedPromiseObj = CheckedUnwrap(promiseObj);
        if (!unwrappedPromiseObj) {
            ReportAccessDenied(cx);
            return false;
        }
        promise = &unwrappedPromiseObj->as<PromiseObject>();
        ar.emplace(cx, promise);
        if (!cx->compartment()->wrap(cx, &resultOrReason)) {
            return false;
        }
    } else {
        promise = promiseObj.as<PromiseObject>();
    }

    return reject
           ? PromiseObject::reject(cx, promise, resultOrReason)
           : PromiseObject::resolve(cx, promise, resultOrReason);
}

JS_PUBLIC_API(bool)
JS::ResolvePromise(JSContext* cx, JS::HandleObject promiseObj, JS::HandleValue resolutionValue)
{
    return ResolveOrRejectPromise(cx, promiseObj, resolutionValue, false);
}

JS_PUBLIC_API(bool)
JS::RejectPromise(JSContext* cx, JS::HandleObject promiseObj, JS::HandleValue rejectionValue)
{
    return ResolveOrRejectPromise(cx, promiseObj, rejectionValue, true);
}

static bool
CallOriginalPromiseThenImpl(JSContext* cx, JS::HandleObject promiseObj,
                            JS::HandleObject onResolvedObj_, JS::HandleObject onRejectedObj_,
                            JS::MutableHandleObject resultObj,
                            CreateDependentPromise createDependent)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(promiseObj, onResolvedObj_, onRejectedObj_);

    MOZ_ASSERT_IF(onResolvedObj_, IsCallable(onResolvedObj_));
    MOZ_ASSERT_IF(onRejectedObj_, IsCallable(onRejectedObj_));
    RootedObject onResolvedObj(cx, onResolvedObj_);
    RootedObject onRejectedObj(cx, onRejectedObj_);

    if (IsWrapper(promiseObj) && !CheckedUnwrap(promiseObj)) {
        ReportAccessDenied(cx);
        return false;
    }
    MOZ_ASSERT(CheckedUnwrap(promiseObj)->is<PromiseObject>());

    RootedValue onFulfilled(cx, ObjectOrNullValue(onResolvedObj));
    RootedValue onRejected(cx, ObjectOrNullValue(onRejectedObj));
    return OriginalPromiseThen(cx, promiseObj, onFulfilled, onRejected, resultObj, createDependent);
}

JS_PUBLIC_API(JSObject*)
JS::CallOriginalPromiseThen(JSContext* cx, JS::HandleObject promiseObj,
                            JS::HandleObject onResolvedObj, JS::HandleObject onRejectedObj)
{
    RootedObject resultPromise(cx);
    if (!CallOriginalPromiseThenImpl(cx, promiseObj, onResolvedObj, onRejectedObj, &resultPromise,
                                     CreateDependentPromise::Always))
    {
        return nullptr;
    }
    return resultPromise;
}

JS_PUBLIC_API(bool)
JS::AddPromiseReactions(JSContext* cx, JS::HandleObject promiseObj,
                        JS::HandleObject onResolvedObj, JS::HandleObject onRejectedObj)
{
    RootedObject resultPromise(cx);
    bool result = CallOriginalPromiseThenImpl(cx, promiseObj, onResolvedObj, onRejectedObj,
                                              &resultPromise, CreateDependentPromise::Never);
    MOZ_ASSERT(!resultPromise);
    return result;
}

JS_PUBLIC_API(JS::PromiseUserInputEventHandlingState)
JS::GetPromiseUserInputEventHandlingState(JS::HandleObject promiseObj_)
{
    JSObject* promiseObj = CheckedUnwrap(promiseObj_);
    if (!promiseObj || !promiseObj->is<PromiseObject>()) {
        return JS::PromiseUserInputEventHandlingState::DontCare;
    }

    auto& promise = promiseObj->as<PromiseObject>();
    if (!promise.requiresUserInteractionHandling()) {
      return JS::PromiseUserInputEventHandlingState::DontCare;
    }
    if (promise.hadUserInteractionUponCreation()) {
      return JS::PromiseUserInputEventHandlingState::HadUserInteractionAtCreation;
    }
    return JS::PromiseUserInputEventHandlingState::DidntHaveUserInteractionAtCreation;
}

JS_PUBLIC_API(bool)
JS::SetPromiseUserInputEventHandlingState(JS::HandleObject promiseObj_,
                                          JS::PromiseUserInputEventHandlingState state)
{
    JSObject* promiseObj = CheckedUnwrap(promiseObj_);
    if (!promiseObj || !promiseObj->is<PromiseObject>()) {
        return false;
    }

    auto& promise = promiseObj->as<PromiseObject>();

    switch (state) {
      case JS::PromiseUserInputEventHandlingState::DontCare:
        promise.setRequiresUserInteractionHandling(false);
        break;
      case JS::PromiseUserInputEventHandlingState::HadUserInteractionAtCreation:
        promise.setRequiresUserInteractionHandling(true);
        promise.setHadUserInteractionUponCreation(true);
        break;
      case JS::PromiseUserInputEventHandlingState::DidntHaveUserInteractionAtCreation:
        promise.setRequiresUserInteractionHandling(true);
        promise.setHadUserInteractionUponCreation(false);
        break;
      default:
        MOZ_ASSERT_UNREACHABLE("Invalid PromiseUserInputEventHandlingState enum value");
        return false;
    }
    return true;
}

/**
 * Unforgeable version of Promise.all for internal use.
 *
 * Takes a dense array of Promise objects and returns a promise that's
 * resolved with an array of resolution values when all those promises ahve
 * been resolved, or rejected with the rejection value of the first rejected
 * promise.
 *
 * Asserts that the array is dense and all entries are Promise objects.
 */
JS_PUBLIC_API(JSObject*)
JS::GetWaitForAllPromise(JSContext* cx, const JS::AutoObjectVector& promises)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);

    return js::GetWaitForAllPromise(cx, promises);
}

JS_PUBLIC_API(void)
JS::InitDispatchToEventLoop(JSContext* cx, JS::DispatchToEventLoopCallback callback, void* closure)
{
    cx->runtime()->offThreadPromiseState.ref().init(callback, closure);
}

JS_PUBLIC_API(void)
JS::ShutdownAsyncTasks(JSContext* cx)
{
    cx->runtime()->offThreadPromiseState.ref().shutdown(cx);
}

JS_PUBLIC_API(bool)
JS::GetOptimizedEncodingBuildId(JS::BuildIdCharVector* buildId)
{
    return wasm::GetOptimizedEncodingBuildId(buildId);
}

JS_PUBLIC_API(void)
JS::InitConsumeStreamCallback(JSContext* cx, ConsumeStreamCallback callback)
{
    cx->runtime()->consumeStreamCallback = callback;
}

JS_PUBLIC_API(void)
JS_RequestInterruptCallback(JSContext* cx)
{
    cx->requestInterrupt(InterruptReason::CallbackUrgent);
}

JS_PUBLIC_API(void)
JS_RequestInterruptCallbackCanWait(JSContext* cx)
{
    cx->requestInterrupt(InterruptReason::CallbackCanWait);
}

JS::AutoSetAsyncStackForNewCalls::AutoSetAsyncStackForNewCalls(
  JSContext* cx, HandleObject stack, const char* asyncCause,
  JS::AutoSetAsyncStackForNewCalls::AsyncCallKind kind)
  : cx(cx),
    oldAsyncStack(cx, cx->asyncStackForNewActivations()),
    oldAsyncCause(cx->asyncCauseForNewActivations),
    oldAsyncCallIsExplicit(cx->asyncCallIsExplicit)
{
    CHECK_THREAD(cx);

    // The option determines whether we actually use the new values at this
    // point. It will not affect restoring the previous values when the object
    // is destroyed, so if the option changes it won't cause consistency issues.
    if (!cx->options().asyncStack()) {
        return;
    }

    SavedFrame* asyncStack = &stack->as<SavedFrame>();

    cx->asyncStackForNewActivations() = asyncStack;
    cx->asyncCauseForNewActivations = asyncCause;
    cx->asyncCallIsExplicit = kind == AsyncCallKind::EXPLICIT;
}

JS::AutoSetAsyncStackForNewCalls::~AutoSetAsyncStackForNewCalls()
{
    cx->asyncCauseForNewActivations = oldAsyncCause;
    cx->asyncStackForNewActivations() =
      oldAsyncStack ? &oldAsyncStack->as<SavedFrame>() : nullptr;
    cx->asyncCallIsExplicit = oldAsyncCallIsExplicit;
}

/************************************************************************/
JS_PUBLIC_API(JSString*)
JS_NewStringCopyN(JSContext* cx, const char* s, size_t n)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    return NewStringCopyN<CanGC>(cx, s, n);
}

JS_PUBLIC_API(JSString*)
JS_NewStringCopyZ(JSContext* cx, const char* s)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    if (!s) {
        return cx->runtime()->emptyString;
    }
    return NewStringCopyZ<CanGC>(cx, s);
}

JS_PUBLIC_API(JSString*)
JS_NewStringCopyUTF8Z(JSContext* cx, const JS::ConstUTF8CharsZ s)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    return NewStringCopyUTF8Z<CanGC>(cx, s);
}

JS_PUBLIC_API(JSString*)
JS_NewStringCopyUTF8N(JSContext* cx, const JS::UTF8Chars s)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    return NewStringCopyUTF8N<CanGC>(cx, s);
}

JS_PUBLIC_API(bool)
JS_StringHasBeenPinned(JSContext* cx, JSString* str)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);

    if (!str->isAtom()) {
        return false;
    }

    return str->asAtom().isPinned();
}

JS_PUBLIC_API(jsid)
INTERNED_STRING_TO_JSID(JSContext* cx, JSString* str)
{
    MOZ_ASSERT(str);
    MOZ_ASSERT(((size_t)str & JSID_TYPE_MASK) == 0);
    MOZ_ASSERT_IF(cx, JS_StringHasBeenPinned(cx, str));
    return AtomToId(&str->asAtom());
}

JS_PUBLIC_API(JSString*)
JS_AtomizeAndPinJSString(JSContext* cx, HandleString str)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    JSAtom* atom = AtomizeString(cx, str, PinAtom);
    MOZ_ASSERT_IF(atom, JS_StringHasBeenPinned(cx, atom));
    return atom;
}

JS_PUBLIC_API(JSString*)
JS_AtomizeString(JSContext* cx, const char* s)
{
    return JS_AtomizeStringN(cx, s, strlen(s));
}

JS_PUBLIC_API(JSString*)
JS_AtomizeStringN(JSContext* cx, const char* s, size_t length)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    return Atomize(cx, s, length, DoNotPinAtom);
}

JS_PUBLIC_API(JSString*)
JS_AtomizeAndPinString(JSContext* cx, const char* s)
{
    return JS_AtomizeAndPinStringN(cx, s, strlen(s));
}

JS_PUBLIC_API(JSString*)
JS_AtomizeAndPinStringN(JSContext* cx, const char* s, size_t length)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    JSAtom* atom = Atomize(cx, s, length, PinAtom);
    MOZ_ASSERT_IF(atom, JS_StringHasBeenPinned(cx, atom));
    return atom;
}

JS_PUBLIC_API(JSString*)
JS_NewLatin1String(JSContext* cx, JS::Latin1Char* chars, size_t length)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    return NewString(cx, chars, length);
}

JS_PUBLIC_API(JSString*)
JS_NewUCString(JSContext* cx, char16_t* chars, size_t length)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    return NewString(cx, chars, length);
}

JS_PUBLIC_API(JSString*)
JS_NewUCStringDontDeflate(JSContext* cx, char16_t* chars, size_t length)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    return NewStringDontDeflate(cx, chars, length);
}

JS_PUBLIC_API(JSString*)
JS_NewUCStringCopyN(JSContext* cx, const char16_t* s, size_t n)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    if (!n) {
        return cx->names().empty;
    }
    return NewStringCopyN<CanGC>(cx, s, n);
}

JS_PUBLIC_API(JSString*)
JS_NewUCStringCopyZ(JSContext* cx, const char16_t* s)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    if (!s) {
        return cx->runtime()->emptyString;
    }
    return NewStringCopyZ<CanGC>(cx, s);
}

JS_PUBLIC_API(JSString*)
JS_AtomizeUCString(JSContext* cx, const char16_t* s)
{
    return JS_AtomizeUCStringN(cx, s, js_strlen(s));
}

JS_PUBLIC_API(JSString*)
JS_AtomizeUCStringN(JSContext* cx, const char16_t* s, size_t length)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    return AtomizeChars(cx, s, length, DoNotPinAtom);
}

JS_PUBLIC_API(JSString*)
JS_AtomizeAndPinUCStringN(JSContext* cx, const char16_t* s, size_t length)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    JSAtom* atom = AtomizeChars(cx, s, length, PinAtom);
    MOZ_ASSERT_IF(atom, JS_StringHasBeenPinned(cx, atom));
    return atom;
}

JS_PUBLIC_API(JSString*)
JS_AtomizeAndPinUCString(JSContext* cx, const char16_t* s)
{
    return JS_AtomizeAndPinUCStringN(cx, s, js_strlen(s));
}

JS_PUBLIC_API(size_t)
JS_GetStringLength(JSString* str)
{
    return str->length();
}

JS_PUBLIC_API(bool)
JS_StringIsFlat(JSString* str)
{
    return str->isFlat();
}

JS_PUBLIC_API(bool)
JS_StringHasLatin1Chars(JSString* str)
{
    return str->hasLatin1Chars();
}

JS_PUBLIC_API(const JS::Latin1Char*)
JS_GetLatin1StringCharsAndLength(JSContext* cx, const JS::AutoRequireNoGC& nogc, JSString* str,
                                 size_t* plength)
{
    MOZ_ASSERT(plength);
    AssertHeapIsIdleOrStringIsFlat(str);
    CHECK_THREAD(cx);
    cx->check(str);
    JSLinearString* linear = str->ensureLinear(cx);
    if (!linear) {
        return nullptr;
    }
    *plength = linear->length();
    return linear->latin1Chars(nogc);
}

JS_PUBLIC_API(const char16_t*)
JS_GetTwoByteStringCharsAndLength(JSContext* cx, const JS::AutoRequireNoGC& nogc, JSString* str,
                                  size_t* plength)
{
    MOZ_ASSERT(plength);
    AssertHeapIsIdleOrStringIsFlat(str);
    CHECK_THREAD(cx);
    cx->check(str);
    JSLinearString* linear = str->ensureLinear(cx);
    if (!linear) {
        return nullptr;
    }
    *plength = linear->length();
    return linear->twoByteChars(nogc);
}

JS_PUBLIC_API(const char16_t*)
JS_GetTwoByteExternalStringChars(JSString* str)
{
    return str->asExternal().twoByteChars();
}

JS_PUBLIC_API(bool)
JS_GetStringCharAt(JSContext* cx, JSString* str, size_t index, char16_t* res)
{
    AssertHeapIsIdleOrStringIsFlat(str);
    CHECK_THREAD(cx);
    cx->check(str);

    JSLinearString* linear = str->ensureLinear(cx);
    if (!linear) {
        return false;
    }

    *res = linear->latin1OrTwoByteChar(index);
    return true;
}

JS_PUBLIC_API(char16_t)
JS_GetFlatStringCharAt(JSFlatString* str, size_t index)
{
    return str->latin1OrTwoByteChar(index);
}

JS_PUBLIC_API(bool)
JS_CopyStringChars(JSContext* cx, mozilla::Range<char16_t> dest, JSString* str)
{
    AssertHeapIsIdleOrStringIsFlat(str);
    CHECK_THREAD(cx);
    cx->check(str);

    JSLinearString* linear = str->ensureLinear(cx);
    if (!linear) {
        return false;
    }

    MOZ_ASSERT(linear->length() <= dest.length());
    CopyChars(dest.begin().get(), *linear);
    return true;
}

JS_PUBLIC_API(const Latin1Char*)
JS_GetLatin1InternedStringChars(const JS::AutoRequireNoGC& nogc, JSString* str)
{
    MOZ_ASSERT(str->isAtom());
    JSFlatString* flat = str->ensureFlat(nullptr);
    if (!flat) {
        return nullptr;
    }
    return flat->latin1Chars(nogc);
}

JS_PUBLIC_API(const char16_t*)
JS_GetTwoByteInternedStringChars(const JS::AutoRequireNoGC& nogc, JSString* str)
{
    MOZ_ASSERT(str->isAtom());
    JSFlatString* flat = str->ensureFlat(nullptr);
    if (!flat) {
        return nullptr;
    }
    return flat->twoByteChars(nogc);
}

extern JS_PUBLIC_API(JSFlatString*)
JS_FlattenString(JSContext* cx, JSString* str)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(str);
    JSFlatString* flat = str->ensureFlat(cx);
    if (!flat) {
        return nullptr;
    }
    return flat;
}

extern JS_PUBLIC_API(const Latin1Char*)
JS_GetLatin1FlatStringChars(const JS::AutoRequireNoGC& nogc, JSFlatString* str)
{
    return str->latin1Chars(nogc);
}

extern JS_PUBLIC_API(const char16_t*)
JS_GetTwoByteFlatStringChars(const JS::AutoRequireNoGC& nogc, JSFlatString* str)
{
    return str->twoByteChars(nogc);
}

JS_PUBLIC_API(bool)
JS_CompareStrings(JSContext* cx, JSString* str1, JSString* str2, int32_t* result)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);

    return CompareStrings(cx, str1, str2, result);
}

JS_PUBLIC_API(bool)
JS_StringEqualsAscii(JSContext* cx, JSString* str, const char* asciiBytes, bool* match)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);

    JSLinearString* linearStr = str->ensureLinear(cx);
    if (!linearStr) {
        return false;
    }
    *match = StringEqualsAscii(linearStr, asciiBytes);
    return true;
}

JS_PUBLIC_API(bool)
JS_FlatStringEqualsAscii(JSFlatString* str, const char* asciiBytes)
{
    return StringEqualsAscii(str, asciiBytes);
}

JS_PUBLIC_API(size_t)
JS_PutEscapedFlatString(char* buffer, size_t size, JSFlatString* str, char quote)
{
    return PutEscapedString(buffer, size, str, quote);
}

JS_PUBLIC_API(size_t)
JS_PutEscapedString(JSContext* cx, char* buffer, size_t size, JSString* str, char quote)
{
    AssertHeapIsIdle();
    JSLinearString* linearStr = str->ensureLinear(cx);
    if (!linearStr) {
        return size_t(-1);
    }
    return PutEscapedString(buffer, size, linearStr, quote);
}

JS_PUBLIC_API(JSString*)
JS_NewDependentString(JSContext* cx, HandleString str, size_t start, size_t length)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    return NewDependentString(cx, str, start, length);
}

JS_PUBLIC_API(JSString*)
JS_ConcatStrings(JSContext* cx, HandleString left, HandleString right)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    return ConcatStrings<CanGC>(cx, left, right);
}

JS_PUBLIC_API(bool)
JS_DecodeBytes(JSContext* cx, const char* src, size_t srclen, char16_t* dst, size_t* dstlenp)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);

    if (!dst) {
        *dstlenp = srclen;
        return true;
    }

    size_t dstlen = *dstlenp;

    if (srclen > dstlen) {
        CopyAndInflateChars(dst, src, dstlen);

        gc::AutoSuppressGC suppress(cx);
        JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_BUFFER_TOO_SMALL);
        return false;
    }

    CopyAndInflateChars(dst, src, srclen);
    *dstlenp = srclen;
    return true;
}

JS_PUBLIC_API(JS::UniqueChars)
JS_EncodeStringToASCII(JSContext* cx, JSString* str)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);

    return js::EncodeAscii(cx, str);
}

JS_PUBLIC_API(JS::UniqueChars)
JS_EncodeStringToLatin1(JSContext* cx, JSString* str)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);

    return js::EncodeLatin1(cx, str);
}

JS_PUBLIC_API(JS::UniqueChars)
JS_EncodeStringToUTF8(JSContext* cx, HandleString str)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);

    return StringToNewUTF8CharsZ(cx, *str);
}

JS_PUBLIC_API(size_t)
JS_GetStringEncodingLength(JSContext* cx, JSString* str)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);

    if (!str->ensureLinear(cx)) {
        return size_t(-1);
    }
    return str->length();
}

JS_PUBLIC_API(bool)
JS_EncodeStringToBuffer(JSContext* cx, JSString* str, char* buffer, size_t length)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);

    JSLinearString* linear = str->ensureLinear(cx);
    if (!linear) {
        return false;
    }

    JS::AutoCheckCannotGC nogc;
    size_t writeLength = Min(linear->length(), length);
    if (linear->hasLatin1Chars()) {
        mozilla::PodCopy(reinterpret_cast<Latin1Char*>(buffer), linear->latin1Chars(nogc),
                         writeLength);
    } else {
        const char16_t* src = linear->twoByteChars(nogc);
        for (size_t i = 0; i < writeLength; i++) {
            buffer[i] = char(src[i]);
        }
    }
    return true;
}

JS_PUBLIC_API(JS::Symbol*)
JS::NewSymbol(JSContext* cx, HandleString description)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    if (description) {
        cx->check(description);
    }

    return Symbol::new_(cx, SymbolCode::UniqueSymbol, description);
}

JS_PUBLIC_API(JS::Symbol*)
JS::GetSymbolFor(JSContext* cx, HandleString key)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(key);

    return Symbol::for_(cx, key);
}

JS_PUBLIC_API(JSString*)
JS::GetSymbolDescription(HandleSymbol symbol)
{
    return symbol->description();
}

JS_PUBLIC_API(JS::SymbolCode)
JS::GetSymbolCode(Handle<Symbol*> symbol)
{
    return symbol->code();
}

JS_PUBLIC_API(JS::Symbol*)
JS::GetWellKnownSymbol(JSContext* cx, JS::SymbolCode which)
{
    return cx->wellKnownSymbols().get(which);
}

#ifdef DEBUG
static bool
PropertySpecNameIsDigits(const char* s) {
    if (JS::PropertySpecNameIsSymbol(s)) {
        return false;
    }
    if (!*s) {
        return false;
    }
    for (; *s; s++) {
        if (*s < '0' || *s > '9') {
            return false;
        }
    }
    return true;
}
#endif // DEBUG

JS_PUBLIC_API(bool)
JS::PropertySpecNameEqualsId(const char* name, HandleId id)
{
    if (JS::PropertySpecNameIsSymbol(name)) {
        if (!JSID_IS_SYMBOL(id)) {
            return false;
        }
        Symbol* sym = JSID_TO_SYMBOL(id);
        return sym->isWellKnownSymbol() && sym->code() == PropertySpecNameToSymbolCode(name);
    }

    MOZ_ASSERT(!PropertySpecNameIsDigits(name));
    return JSID_IS_ATOM(id) && JS_FlatStringEqualsAscii(JSID_TO_ATOM(id), name);
}

JS_PUBLIC_API(bool)
JS_Stringify(JSContext* cx, MutableHandleValue vp, HandleObject replacer,
             HandleValue space, JSONWriteCallback callback, void* data)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(replacer, space);
    StringBuffer sb(cx);
    if (!sb.ensureTwoByteChars()) {
        return false;
    }
    if (!Stringify(cx, vp, replacer, space, sb, StringifyBehavior::Normal)) {
        return false;
    }
    if (sb.empty() && !sb.append(cx->names().null)) {
        return false;
    }
    return callback(sb.rawTwoByteBegin(), sb.length(), data);
}

JS_PUBLIC_API(bool)
JS::ToJSONMaybeSafely(JSContext* cx, JS::HandleObject input,
                      JSONWriteCallback callback, void* data)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(input);

    StringBuffer sb(cx);
    if (!sb.ensureTwoByteChars()) {
        return false;
    }

    RootedValue inputValue(cx, ObjectValue(*input));
    if (!Stringify(cx, &inputValue, nullptr, NullHandleValue, sb,
                   StringifyBehavior::RestrictedSafe))
        return false;

    if (sb.empty() && !sb.append(cx->names().null)) {
        return false;
    }

    return callback(sb.rawTwoByteBegin(), sb.length(), data);
}

JS_PUBLIC_API(bool)
JS_ParseJSON(JSContext* cx, const char16_t* chars, uint32_t len, MutableHandleValue vp)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    return ParseJSONWithReviver(cx, mozilla::Range<const char16_t>(chars, len), NullHandleValue, vp);
}

JS_PUBLIC_API(bool)
JS_ParseJSON(JSContext* cx, HandleString str, MutableHandleValue vp)
{
    return JS_ParseJSONWithReviver(cx, str, NullHandleValue, vp);
}

JS_PUBLIC_API(bool)
JS_ParseJSONWithReviver(JSContext* cx, const char16_t* chars, uint32_t len, HandleValue reviver, MutableHandleValue vp)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    return ParseJSONWithReviver(cx, mozilla::Range<const char16_t>(chars, len), reviver, vp);
}

JS_PUBLIC_API(bool)
JS_ParseJSONWithReviver(JSContext* cx, HandleString str, HandleValue reviver, MutableHandleValue vp)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(str);

    AutoStableStringChars stableChars(cx);
    if (!stableChars.init(cx, str)) {
        return false;
    }

    return stableChars.isLatin1()
           ? ParseJSONWithReviver(cx, stableChars.latin1Range(), reviver, vp)
           : ParseJSONWithReviver(cx, stableChars.twoByteRange(), reviver, vp);
}

/************************************************************************/

JS_PUBLIC_API(void)
JS_ReportErrorASCII(JSContext* cx, const char* format, ...)
{
    va_list ap;

    AssertHeapIsIdle();
    va_start(ap, format);
    ReportErrorVA(cx, JSREPORT_ERROR, format, ArgumentsAreASCII, ap);
    va_end(ap);
}

JS_PUBLIC_API(void)
JS_ReportErrorLatin1(JSContext* cx, const char* format, ...)
{
    va_list ap;

    AssertHeapIsIdle();
    va_start(ap, format);
    ReportErrorVA(cx, JSREPORT_ERROR, format, ArgumentsAreLatin1, ap);
    va_end(ap);
}

JS_PUBLIC_API(void)
JS_ReportErrorUTF8(JSContext* cx, const char* format, ...)
{
    va_list ap;

    AssertHeapIsIdle();
    va_start(ap, format);
    ReportErrorVA(cx, JSREPORT_ERROR, format, ArgumentsAreUTF8, ap);
    va_end(ap);
}

JS_PUBLIC_API(void)
JS_ReportErrorNumberASCII(JSContext* cx, JSErrorCallback errorCallback,
                          void* userRef, const unsigned errorNumber, ...)
{
    va_list ap;
    va_start(ap, errorNumber);
    JS_ReportErrorNumberASCIIVA(cx, errorCallback, userRef, errorNumber, ap);
    va_end(ap);
}

JS_PUBLIC_API(void)
JS_ReportErrorNumberASCIIVA(JSContext* cx, JSErrorCallback errorCallback,
                            void* userRef, const unsigned errorNumber,
                            va_list ap)
{
    AssertHeapIsIdle();
    ReportErrorNumberVA(cx, JSREPORT_ERROR, errorCallback, userRef,
                        errorNumber, ArgumentsAreASCII, ap);
}

JS_PUBLIC_API(void)
JS_ReportErrorNumberLatin1(JSContext* cx, JSErrorCallback errorCallback,
                           void* userRef, const unsigned errorNumber, ...)
{
    va_list ap;
    va_start(ap, errorNumber);
    JS_ReportErrorNumberLatin1VA(cx, errorCallback, userRef, errorNumber, ap);
    va_end(ap);
}

JS_PUBLIC_API(void)
JS_ReportErrorNumberLatin1VA(JSContext* cx, JSErrorCallback errorCallback,
                             void* userRef, const unsigned errorNumber,
                             va_list ap)
{
    AssertHeapIsIdle();
    ReportErrorNumberVA(cx, JSREPORT_ERROR, errorCallback, userRef,
                        errorNumber, ArgumentsAreLatin1, ap);
}

JS_PUBLIC_API(void)
JS_ReportErrorNumberUTF8(JSContext* cx, JSErrorCallback errorCallback,
                         void* userRef, const unsigned errorNumber, ...)
{
    va_list ap;
    va_start(ap, errorNumber);
    JS_ReportErrorNumberUTF8VA(cx, errorCallback, userRef, errorNumber, ap);
    va_end(ap);
}

JS_PUBLIC_API(void)
JS_ReportErrorNumberUTF8VA(JSContext* cx, JSErrorCallback errorCallback,
                           void* userRef, const unsigned errorNumber,
                           va_list ap)
{
    AssertHeapIsIdle();
    ReportErrorNumberVA(cx, JSREPORT_ERROR, errorCallback, userRef,
                        errorNumber, ArgumentsAreUTF8, ap);
}

JS_PUBLIC_API(void)
JS_ReportErrorNumberUC(JSContext* cx, JSErrorCallback errorCallback,
                       void* userRef, const unsigned errorNumber, ...)
{
    va_list ap;

    AssertHeapIsIdle();
    va_start(ap, errorNumber);
    ReportErrorNumberVA(cx, JSREPORT_ERROR, errorCallback, userRef,
                        errorNumber, ArgumentsAreUnicode, ap);
    va_end(ap);
}

JS_PUBLIC_API(void)
JS_ReportErrorNumberUCArray(JSContext* cx, JSErrorCallback errorCallback,
                            void* userRef, const unsigned errorNumber,
                            const char16_t** args)
{
    AssertHeapIsIdle();
    ReportErrorNumberUCArray(cx, JSREPORT_ERROR, errorCallback, userRef,
                             errorNumber, args);
}

JS_PUBLIC_API(bool)
JS_ReportWarningASCII(JSContext* cx, const char* format, ...)
{
    va_list ap;
    bool ok;

    AssertHeapIsIdle();
    va_start(ap, format);
    ok = ReportErrorVA(cx, JSREPORT_WARNING, format, ArgumentsAreASCII, ap);
    va_end(ap);
    return ok;
}

JS_PUBLIC_API(bool)
JS_ReportWarningLatin1(JSContext* cx, const char* format, ...)
{
    va_list ap;
    bool ok;

    AssertHeapIsIdle();
    va_start(ap, format);
    ok = ReportErrorVA(cx, JSREPORT_WARNING, format, ArgumentsAreLatin1, ap);
    va_end(ap);
    return ok;
}

JS_PUBLIC_API(bool)
JS_ReportWarningUTF8(JSContext* cx, const char* format, ...)
{
    va_list ap;
    bool ok;

    AssertHeapIsIdle();
    va_start(ap, format);
    ok = ReportErrorVA(cx, JSREPORT_WARNING, format, ArgumentsAreUTF8, ap);
    va_end(ap);
    return ok;
}

JS_PUBLIC_API(bool)
JS_ReportErrorFlagsAndNumberASCII(JSContext* cx, unsigned flags,
                                  JSErrorCallback errorCallback, void* userRef,
                                  const unsigned errorNumber, ...)
{
    va_list ap;
    bool ok;

    AssertHeapIsIdle();
    va_start(ap, errorNumber);
    ok = ReportErrorNumberVA(cx, flags, errorCallback, userRef,
                             errorNumber, ArgumentsAreASCII, ap);
    va_end(ap);
    return ok;
}

JS_PUBLIC_API(bool)
JS_ReportErrorFlagsAndNumberLatin1(JSContext* cx, unsigned flags,
                                   JSErrorCallback errorCallback, void* userRef,
                                   const unsigned errorNumber, ...)
{
    va_list ap;
    bool ok;

    AssertHeapIsIdle();
    va_start(ap, errorNumber);
    ok = ReportErrorNumberVA(cx, flags, errorCallback, userRef,
                             errorNumber, ArgumentsAreLatin1, ap);
    va_end(ap);
    return ok;
}

JS_PUBLIC_API(bool)
JS_ReportErrorFlagsAndNumberUTF8(JSContext* cx, unsigned flags,
                                 JSErrorCallback errorCallback, void* userRef,
                                 const unsigned errorNumber, ...)
{
    va_list ap;
    bool ok;

    AssertHeapIsIdle();
    va_start(ap, errorNumber);
    ok = ReportErrorNumberVA(cx, flags, errorCallback, userRef,
                             errorNumber, ArgumentsAreUTF8, ap);
    va_end(ap);
    return ok;
}

JS_PUBLIC_API(bool)
JS_ReportErrorFlagsAndNumberUC(JSContext* cx, unsigned flags,
                               JSErrorCallback errorCallback, void* userRef,
                               const unsigned errorNumber, ...)
{
    va_list ap;
    bool ok;

    AssertHeapIsIdle();
    va_start(ap, errorNumber);
    ok = ReportErrorNumberVA(cx, flags, errorCallback, userRef,
                             errorNumber, ArgumentsAreUnicode, ap);
    va_end(ap);
    return ok;
}

JS_PUBLIC_API(void)
JS_ReportOutOfMemory(JSContext* cx)
{
    ReportOutOfMemory(cx);
}

JS_PUBLIC_API(void)
JS_ReportAllocationOverflow(JSContext* cx)
{
    ReportAllocationOverflow(cx);
}

JS_PUBLIC_API(JS::WarningReporter)
JS::GetWarningReporter(JSContext* cx)
{
    return cx->runtime()->warningReporter;
}

JS_PUBLIC_API(JS::WarningReporter)
JS::SetWarningReporter(JSContext* cx, JS::WarningReporter reporter)
{
    WarningReporter older = cx->runtime()->warningReporter;
    cx->runtime()->warningReporter = reporter;
    return older;
}

/************************************************************************/

/*
 * Dates.
 */
JS_PUBLIC_API(JSObject*)
JS_NewDateObject(JSContext* cx, int year, int mon, int mday, int hour, int min, int sec)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    return NewDateObject(cx, year, mon, mday, hour, min, sec);
}

JS_PUBLIC_API(JSObject*)
JS::NewDateObject(JSContext* cx, JS::ClippedTime time)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    return NewDateObjectMsec(cx, time);
}

JS_PUBLIC_API(bool)
JS_ObjectIsDate(JSContext* cx, HandleObject obj, bool* isDate)
{
    cx->check(obj);

    ESClass cls;
    if (!GetBuiltinClass(cx, obj, &cls)) {
        return false;
    }

    *isDate = cls == ESClass::Date;
    return true;
}

/************************************************************************/

/*
 * Regular Expressions.
 */
JS_PUBLIC_API(JSObject*)
JS_NewRegExpObject(JSContext* cx, const char* bytes, size_t length, unsigned flags)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);

    UniqueTwoByteChars chars(InflateString(cx, bytes, length));
    if (!chars) {
        return nullptr;
    }

    return RegExpObject::create(cx, chars.get(), length, RegExpFlag(flags), GenericObject);
}

JS_PUBLIC_API(JSObject*)
JS_NewUCRegExpObject(JSContext* cx, const char16_t* chars, size_t length, unsigned flags)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);

    return RegExpObject::create(cx, chars, length, RegExpFlag(flags), GenericObject);
}

JS_PUBLIC_API(bool)
JS_SetRegExpInput(JSContext* cx, HandleObject obj, HandleString input)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(input);

    Handle<GlobalObject*> global = obj.as<GlobalObject>();
    RegExpStatics* res = GlobalObject::getRegExpStatics(cx, global);
    if (!res) {
        return false;
    }

    res->reset(input);
    return true;
}

JS_PUBLIC_API(bool)
JS_ClearRegExpStatics(JSContext* cx, HandleObject obj)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    MOZ_ASSERT(obj);

    Handle<GlobalObject*> global = obj.as<GlobalObject>();
    RegExpStatics* res = GlobalObject::getRegExpStatics(cx, global);
    if (!res) {
        return false;
    }

    res->clear();
    return true;
}

JS_PUBLIC_API(bool)
JS_ExecuteRegExp(JSContext* cx, HandleObject obj, HandleObject reobj, char16_t* chars,
                 size_t length, size_t* indexp, bool test, MutableHandleValue rval)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);

    Handle<GlobalObject*> global = obj.as<GlobalObject>();
    RegExpStatics* res = GlobalObject::getRegExpStatics(cx, global);
    if (!res) {
        return false;
    }

    RootedLinearString input(cx, NewStringCopyN<CanGC>(cx, chars, length));
    if (!input) {
        return false;
    }

    return ExecuteRegExpLegacy(cx, res, reobj.as<RegExpObject>(), input, indexp, test, rval);
}

JS_PUBLIC_API(bool)
JS_ExecuteRegExpNoStatics(JSContext* cx, HandleObject obj, char16_t* chars, size_t length,
                          size_t* indexp, bool test, MutableHandleValue rval)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);

    RootedLinearString input(cx, NewStringCopyN<CanGC>(cx, chars, length));
    if (!input) {
        return false;
    }

    return ExecuteRegExpLegacy(cx, nullptr, obj.as<RegExpObject>(), input, indexp, test,
                               rval);
}

JS_PUBLIC_API(bool)
JS_ObjectIsRegExp(JSContext* cx, HandleObject obj, bool* isRegExp)
{
    cx->check(obj);

    ESClass cls;
    if (!GetBuiltinClass(cx, obj, &cls)) {
        return false;
    }

    *isRegExp = cls == ESClass::RegExp;
    return true;
}

JS_PUBLIC_API(unsigned)
JS_GetRegExpFlags(JSContext* cx, HandleObject obj)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);

    RegExpShared* shared = RegExpToShared(cx, obj);
    if (!shared) {
        return false;
    }
    return shared->getFlags();
}

JS_PUBLIC_API(JSString*)
JS_GetRegExpSource(JSContext* cx, HandleObject obj)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);

    RegExpShared* shared = RegExpToShared(cx, obj);
    if (!shared) {
        return nullptr;
    }
    return shared->getSource();
}

/************************************************************************/

JS_PUBLIC_API(bool)
JS_SetDefaultLocale(JSRuntime* rt, const char* locale)
{
    AssertHeapIsIdle();
    return rt->setDefaultLocale(locale);
}

JS_PUBLIC_API(UniqueChars)
JS_GetDefaultLocale(JSContext* cx)
{
    AssertHeapIsIdle();
    if (const char* locale = cx->runtime()->getDefaultLocale()) {
        return DuplicateString(cx, locale);
    }

    return nullptr;
}

JS_PUBLIC_API(void)
JS_ResetDefaultLocale(JSRuntime* rt)
{
    AssertHeapIsIdle();
    rt->resetDefaultLocale();
}

JS_PUBLIC_API(void)
JS_SetLocaleCallbacks(JSRuntime* rt, const JSLocaleCallbacks* callbacks)
{
    AssertHeapIsIdle();
    rt->localeCallbacks = callbacks;
}

JS_PUBLIC_API(const JSLocaleCallbacks*)
JS_GetLocaleCallbacks(JSRuntime* rt)
{
    /* This function can be called by a finalizer. */
    return rt->localeCallbacks;
}

/************************************************************************/

JS_PUBLIC_API(bool)
JS_IsExceptionPending(JSContext* cx)
{
    /* This function can be called by a finalizer. */
    return (bool) cx->isExceptionPending();
}

JS_PUBLIC_API(bool)
JS_GetPendingException(JSContext* cx, MutableHandleValue vp)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    if (!cx->isExceptionPending()) {
        return false;
    }
    return cx->getPendingException(vp);
}

JS_PUBLIC_API(void)
JS_SetPendingException(JSContext* cx, HandleValue value)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    cx->check(value);
    cx->setPendingException(value);
}

JS_PUBLIC_API(void)
JS_ClearPendingException(JSContext* cx)
{
    AssertHeapIsIdle();
    cx->clearPendingException();
}

JS::AutoSaveExceptionState::AutoSaveExceptionState(JSContext* cx)
  : context(cx),
    wasPropagatingForcedReturn(cx->propagatingForcedReturn_),
    wasOverRecursed(cx->overRecursed_),
    wasThrowing(cx->throwing),
    exceptionValue(cx)
{
    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    if (wasPropagatingForcedReturn) {
        cx->clearPropagatingForcedReturn();
    }
    if (wasOverRecursed) {
        cx->overRecursed_ = false;
    }
    if (wasThrowing) {
        exceptionValue = cx->unwrappedException();
        cx->clearPendingException();
    }
}

void
JS::AutoSaveExceptionState::restore()
{
    context->propagatingForcedReturn_ = wasPropagatingForcedReturn;
    context->overRecursed_ = wasOverRecursed;
    context->throwing = wasThrowing;
    context->unwrappedException() = exceptionValue;
    drop();
}

JS::AutoSaveExceptionState::~AutoSaveExceptionState()
{
    if (!context->isExceptionPending()) {
        if (wasPropagatingForcedReturn) {
            context->setPropagatingForcedReturn();
        }
        if (wasThrowing) {
            context->overRecursed_ = wasOverRecursed;
            context->throwing = true;
            context->unwrappedException() = exceptionValue;
        }
    }
}

struct JSExceptionState {
    explicit JSExceptionState(JSContext* cx)
      : throwing(false),
        exception(cx)
    {}
    bool throwing;
    PersistentRootedValue exception;
};

JS_PUBLIC_API(JSExceptionState*)
JS_SaveExceptionState(JSContext* cx)
{
    JSExceptionState* state;

    AssertHeapIsIdle();
    CHECK_THREAD(cx);
    state = cx->new_<JSExceptionState>(cx);
    if (state) {
        state->throwing = JS_GetPendingException(cx, &state->exception);
    }
    return state;