Method get

rhino/src/main/java/org/mozilla/javascript/NativeProxy.java:366–414

see 10.5.8 [[Get]] (P, Receiver)

(String name, Scriptable start)

     * [[Get]] (P, Receiver)</a>
     */
    @Override
    public Object get(String name, Scriptable start) {
        /*
         * 1. Assert: IsPropertyKey(P) is true.
         * 2. Let handler be O.[[ProxyHandler]].
         * 3. If handler is null, throw a TypeError exception.
         * 4. Assert: Type(handler) is Object.
         * 5. Let target be O.[[ProxyTarget]].
         * 6. Let trap be ? GetMethod(handler, "get").
         * 7. If trap is undefined, then
         *     a. Return ? target.[[Get]](P, Receiver).
         * 8. Let trapResult be ? Call(trap, handler, « target, P, Receiver »).
         * 9. Let targetDesc be ? target.[[GetOwnProperty]](P).
         * 10. If targetDesc is not undefined and targetDesc.[[Configurable]] is false, then
         *     a. If IsDataDescriptor(targetDesc) is true and targetDesc.[[Writable]] is false, then
         *         i. If SameValue(trapResult, targetDesc.[[Value]]) is false, throw a TypeError exception.
         *     b. If IsAccessorDescriptor(targetDesc) is true and targetDesc.[[Get]] is undefined, then
         *         i. If trapResult is not undefined, throw a TypeError exception.
         * 11. Return trapResult.
         */
        ScriptableObject target = getTargetThrowIfRevoked();

        Function trap = getTrap(TRAP_GET);
        if (trap != null) {
            Object trapResult = callTrap(trap, new Object[] {target, name, start});

            DescriptorInfo targetDesc = target.getOwnPropertyDescriptor(Context.getContext(), name);
            if (targetDesc != null && targetDesc.isConfigurable(false)) {
                if (targetDesc.isDataDescriptor() && targetDesc.isWritable(false)) {
                    if (!Objects.equals(trapResult, targetDesc.value)) {
                        throw ScriptRuntime.typeError(
                                "proxy get has to return the same value as the plain call");
                    }
                }
                if (targetDesc.isAccessorDescriptor() && Undefined.isUndefined(targetDesc.getter)) {
                    if (!Undefined.isUndefined(trapResult)) {
                        throw ScriptRuntime.typeError(
                                "proxy get has to return the same value as the plain call");
                    }
                }
            }
            return trapResult;
        }

        if (start == this) {
            start = target;
        }
        return target.get(name, start);
    }

    /**
     * see <a