jsiter.c

java script test programing source code

                          JSITER_KEYVALUE)));

    /* JSITER_KEYVALUE must always come with JSITER_FOREACH */
    JS_ASSERT(!(flags & JSITER_KEYVALUE) || (flags & JSITER_FOREACH));

    /* XXX work around old valueOf call hidden beneath js_ValueToObject */
    if (!JSVAL_IS_PRIMITIVE(*vp)) {
        obj = JSVAL_TO_OBJECT(*vp);
    } else {
        /*
         * Enumerating over null and undefined gives an empty enumerator.
         * This is contrary to ECMA-262 9.9 ToObject, invoked from step 3 of
         * the first production in 12.6.4 and step 4 of the second production,
         * but it's "web JS" compatible.
         */
        if ((flags & JSITER_ENUMERATE)) {
            if (!js_ValueToObject(cx, *vp, &obj))
                return JS_FALSE;
            if (!obj)
                goto default_iter;
        } else {
            obj = js_ValueToNonNullObject(cx, *vp);
            if (!obj)
                return JS_FALSE;
        }
    }

    JS_ASSERT(obj);
    JS_PUSH_TEMP_ROOT_OBJECT(cx, obj, &tvr);

    atom = cx->runtime->atomState.iteratorAtom;
#if JS_HAS_XML_SUPPORT
    if (OBJECT_IS_XML(cx, obj)) {
        if (!js_GetXMLFunction(cx, obj, ATOM_TO_JSID(atom), vp))
            goto bad;
    } else
#endif
    {
        if (!OBJ_GET_PROPERTY(cx, obj, ATOM_TO_JSID(atom), vp))
            goto bad;
    }

    if (JSVAL_IS_VOID(*vp)) {
      default_iter:
        /*
         * Fail over to the default enumerating native iterator.
         *
         * Create iterobj with a NULL parent to ensure that we use the correct
         * scope chain to lookup the iterator's constructor. Since we use the
         * parent slot to keep track of the iterable, we must fix it up after.
         */
        iterobj = js_NewObject(cx, &js_IteratorClass, NULL, NULL);
        if (!iterobj)
            goto bad;

        /* Store iterobj in *vp to protect it from GC (callers must root vp). */
        *vp = OBJECT_TO_JSVAL(iterobj);

        if (!InitNativeIterator(cx, iterobj, obj, flags))
            goto bad;
    } else {
        arg = BOOLEAN_TO_JSVAL((flags & JSITER_FOREACH) == 0);
        if (!js_InternalInvoke(cx, obj, *vp, JSINVOKE_ITERATOR, 1, &arg, vp))
            goto bad;
        if (JSVAL_IS_PRIMITIVE(*vp)) {
            str = js_DecompileValueGenerator(cx, JSDVG_SEARCH_STACK, *vp, NULL);
            if (str) {
                JS_ReportErrorNumberUC(cx, js_GetErrorMessage, NULL,
                                       JSMSG_BAD_ITERATOR_RETURN,
                                       JSSTRING_CHARS(str),
                                       JSSTRING_CHARS(ATOM_TO_STRING(atom)));
            }
            goto bad;
        }
    }

    ok = JS_TRUE;
  out:
    if (obj)
        JS_POP_TEMP_ROOT(cx, &tvr);
    return ok;
  bad:
    ok = JS_FALSE;
    goto out;
}

static JSBool
CallEnumeratorNext(JSContext *cx, JSObject *iterobj, uintN flags, jsval *rval)
{
    JSObject *obj, *origobj;
    jsval state;
    JSBool foreach;
    jsid id;
    JSObject *obj2;
    JSBool cond;
    JSClass *clasp;
    JSExtendedClass *xclasp;
    JSProperty *prop;
    JSString *str;

    JS_ASSERT(flags & JSITER_ENUMERATE);
    JS_ASSERT(JSVAL_TO_PRIVATE(iterobj->slots[JSSLOT_CLASS]) ==
              &js_IteratorClass);

    obj = JSVAL_TO_OBJECT(iterobj->slots[JSSLOT_PARENT]);
    origobj = JSVAL_TO_OBJECT(iterobj->slots[JSSLOT_PROTO]);
    state = iterobj->slots[JSSLOT_ITER_STATE];
    if (JSVAL_IS_NULL(state))
        goto stop;

    foreach = (flags & JSITER_FOREACH) != 0;
#if JS_HAS_XML_SUPPORT
    /*
     * Treat an XML object specially only when it starts the prototype chain.
     * Otherwise we need to do the usual deleted and shadowed property checks.
     */
    if (obj == origobj && OBJECT_IS_XML(cx, obj)) {
        if (foreach) {
            JSXMLObjectOps *xmlops = (JSXMLObjectOps *) obj->map->ops;

            if (!xmlops->enumerateValues(cx, obj, JSENUMERATE_NEXT, &state,
                                         &id, rval)) {
                return JS_FALSE;
            }
        } else {
            if (!OBJ_ENUMERATE(cx, obj, JSENUMERATE_NEXT, &state, &id))
                return JS_FALSE;
        }
        iterobj->slots[JSSLOT_ITER_STATE] = state;
        if (JSVAL_IS_NULL(state))
            goto stop;
    } else
#endif
    {
      restart:
        if (!OBJ_ENUMERATE(cx, obj, JSENUMERATE_NEXT, &state, &id))
            return JS_TRUE;

        iterobj->slots[JSSLOT_ITER_STATE] = state;
        if (JSVAL_IS_NULL(state)) {
#if JS_HAS_XML_SUPPORT
            if (OBJECT_IS_XML(cx, obj)) {
                /*
                 * We just finished enumerating an XML obj that is present on
                 * the prototype chain of a non-XML origobj. Stop further
                 * prototype chain searches because XML objects don't
                 * enumerate prototypes.
                 */
                JS_ASSERT(origobj != obj);
                JS_ASSERT(!OBJECT_IS_XML(cx, origobj));
            } else
#endif
            {
                obj = OBJ_GET_PROTO(cx, obj);
                if (obj) {
                    iterobj->slots[JSSLOT_PARENT] = OBJECT_TO_JSVAL(obj);
                    if (!OBJ_ENUMERATE(cx, obj, JSENUMERATE_INIT, &state, NULL))
                        return JS_FALSE;
                    iterobj->slots[JSSLOT_ITER_STATE] = state;
                    if (!JSVAL_IS_NULL(state))
                        goto restart;
                }
            }
            goto stop;
        }

        /* Skip properties not in obj when looking from origobj. */
        if (!OBJ_LOOKUP_PROPERTY(cx, origobj, id, &obj2, &prop))
            return JS_FALSE;
        if (!prop)
            goto restart;
        OBJ_DROP_PROPERTY(cx, obj2, prop);

        /*
         * If the id was found in a prototype object or an unrelated object
         * (specifically, not in an inner object for obj), skip it. This step
         * means that all OBJ_LOOKUP_PROPERTY implementations must return an
         * object further along on the prototype chain, or else possibly an
         * object returned by the JSExtendedClass.outerObject optional hook.
         */
        if (obj != obj2) {
            cond = JS_FALSE;
            clasp = OBJ_GET_CLASS(cx, obj2);
            if (clasp->flags & JSCLASS_IS_EXTENDED) {
                xclasp = (JSExtendedClass *) clasp;
                cond = xclasp->outerObject &&
                    xclasp->outerObject(cx, obj2) == obj;
            }
            if (!cond)
                goto restart;
        }

        if (foreach) {
            /* Get property querying the original object. */
            if (!OBJ_GET_PROPERTY(cx, origobj, id, rval))
                return JS_FALSE;
        }
    }

    if (foreach) {
        if (flags & JSITER_KEYVALUE) {
            if (!NewKeyValuePair(cx, id, *rval, rval))
                return JS_FALSE;
        }
    } else {
        /* Make rval a string for uniformity and compatibility. */
        if (JSID_IS_ATOM(id)) {
            *rval = ATOM_KEY(JSID_TO_ATOM(id));
        }
#if JS_HAS_XML_SUPPORT
        else if (JSID_IS_OBJECT(id)) {
            str = js_ValueToString(cx, OBJECT_JSID_TO_JSVAL(id));
            if (!str)
                return JS_FALSE;
            *rval = STRING_TO_JSVAL(str);
        }
#endif
        else {
            str = js_NumberToString(cx, (jsdouble)JSID_TO_INT(id));
            if (!str)
                return JS_FALSE;
            *rval = STRING_TO_JSVAL(str);
        }
    }
    return JS_TRUE;

  stop:
    JS_ASSERT(iterobj->slots[JSSLOT_ITER_STATE] == JSVAL_NULL);
    *rval = JSVAL_HOLE;
    return JS_TRUE;
}

JSBool
js_CallIteratorNext(JSContext *cx, JSObject *iterobj, jsval *rval)
{
    uintN flags;

    /* Fast path for native iterators */
    if (OBJ_GET_CLASS(cx, iterobj) == &js_IteratorClass) {
        flags = JSVAL_TO_INT(OBJ_GET_SLOT(cx, iterobj, JSSLOT_ITER_FLAGS));
        if (flags & JSITER_ENUMERATE)
            return CallEnumeratorNext(cx, iterobj, flags, rval);

        /*
         * Call next directly as all the methods of the native iterator are
         * read-only and permanent.
         */
        if (!IteratorNextImpl(cx, iterobj, rval))
            return JS_FALSE;
    } else {
        jsid id = ATOM_TO_JSID(cx->runtime->atomState.nextAtom);

        if (!JS_GetMethodById(cx, iterobj, id, &iterobj, rval))
            return JS_FALSE;
        if (!js_InternalCall(cx, iterobj, *rval, 0, NULL, rval)) {
            /* Check for StopIteration. */
            if (!cx->throwing ||
                JSVAL_IS_PRIMITIVE(cx->exception) ||
                OBJ_GET_CLASS(cx, JSVAL_TO_OBJECT(cx->exception))
                    != &js_StopIterationClass) {
                return JS_FALSE;
            }

            /* Inline JS_ClearPendingException(cx). */
            cx->throwing = JS_FALSE;
            cx->exception = JSVAL_VOID;
            *rval = JSVAL_HOLE;
            return JS_TRUE;
        }
    }

    return JS_TRUE;
}

static JSBool
stopiter_hasInstance(JSContext *cx, JSObject *obj, jsval v, JSBool *bp)
{
    *bp = !JSVAL_IS_PRIMITIVE(v) &&
          OBJ_GET_CLASS(cx, JSVAL_TO_OBJECT(v)) == &js_StopIterationClass;
    return JS_TRUE;
}

JSClass js_StopIterationClass = {
    js_StopIteration_str,
    JSCLASS_HAS_CACHED_PROTO(JSProto_StopIteration),
    JS_PropertyStub,  JS_PropertyStub,
    JS_PropertyStub,  JS_PropertyStub,
    JS_EnumerateStub, JS_ResolveStub,
    JS_ConvertStub,   JS_FinalizeStub,
    NULL,             NULL,
    NULL,             NULL,
    NULL,             stopiter_hasInstance,
    NULL,             NULL
};

#if JS_HAS_GENERATORS

static void
generator_finalize(JSContext *cx, JSObject *obj)
{
    JSGenerator *gen;

    gen = (JSGenerator *) JS_GetPrivate(cx, obj);
    if (gen) {
        /*
         * gen can be open on shutdown when close hooks are ignored or when
         * the embedding cancels scheduled close hooks.
         */
        JS_ASSERT(gen->state == JSGEN_NEWBORN || gen->state == JSGEN_CLOSED ||
                  gen->state == JSGEN_OPEN);
        JS_free(cx, gen);
    }
}

static uint32
generator_mark(JSContext *cx, JSObject *obj, void *arg)
{
    JSGenerator *gen;

    gen = (JSGenerator *) JS_GetPrivate(cx, obj);
    if (gen) {
        /*
         * We must mark argv[-2], as js_MarkStackFrame will not.  Note that
         * js_MarkStackFrame will mark thisp (argv[-1]) and actual arguments,
         * plus any missing formals and local GC roots.
         */
        JS_ASSERT(!JSVAL_IS_PRIMITIVE(gen->frame.argv[-2]));
        GC_MARK(cx, JSVAL_TO_GCTHING(gen->frame.argv[-2]), "generator");
        js_MarkStackFrame(cx, &gen->frame);
    }
    return 0;
}

JSClass js_GeneratorClass = {
    js_Generator_str,
    JSCLASS_HAS_PRIVATE | JSCLASS_IS_ANONYMOUS |
    JSCLASS_HAS_CACHED_PROTO(JSProto_Generator),
    JS_PropertyStub,  JS_PropertyStub, JS_PropertyStub, JS_PropertyStub,
    JS_EnumerateStub, JS_ResolveStub,  JS_ConvertStub,  generator_finalize,
    NULL,             NULL,            NULL,            NULL,
    NULL,             NULL,            generator_mark,  NULL
};

/*
 * Called from the JSOP_GENERATOR case in the interpreter, with fp referring
 * to the frame by which the generator function was activated.  Create a new
 * JSGenerator object, which contains its own JSStackFrame that we populate
 * from *fp.  We know that upon return, the JSOP_GENERATOR opcode will return
 * from the activation in fp, so we can steal away fp->callobj and fp->argsobj
 * if they are non-null.
 */
JSObject *
js_NewGenerator(JSContext *cx, JSStackFrame *fp)
{
    JSObject *obj;
    uintN argc, nargs, nvars, depth, nslots;
    JSGenerator *gen;
    jsval *newsp;

    /* After the following return, failing control flow must goto bad. */
    obj = js_NewObject(cx, &js_GeneratorClass, NULL, NULL);