1083752 - Calling Map/Set/WeakMap() (without `new`) should throw

Status: RESOLVED FIXED

(Core :: JavaScript Engine, defect)

Description

[Mariusz Nowak]

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.9; rv:36.0) Gecko/20100101 Firefox/36.0
Build ID: 20141016030201

Steps to reproduce:

Just run:

Set();


Actual results:

New set instance was returned


Expected results:

If understand ES6 spec correctly, it should throw with TypeError

Comment 3

[Leo Balter]

The same error occurs on Map and WeakMap.

Comment 4

[Tom S]

Attachment: Throw when calling Map/Set/WeakMap/

I think it's time to do this. We landed the warning for this in 38 with bug 1108930.

Comment 5

[Jeff Walden [:Waldo]]

Comment on attachment 8636833 [details] [diff] [review]
Throw when calling Map/Set/WeakMap/

Review of attachment 8636833 [details] [diff] [review]:
-----------------------------------------------------------------

::: js/src/builtin/MapObject.cpp
@@ +1237,5 @@
>  MapObject::construct(JSContext* cx, unsigned argc, Value* vp)
>  {
>      Rooted<MapObject*> obj(cx, MapObject::create(cx));
>      if (!obj)
>          return false;

Mind moving this down below the ThrowIfNotConstructing call?

@@ +1902,5 @@
>  SetObject::construct(JSContext* cx, unsigned argc, Value* vp)
>  {
>      Rooted<SetObject*> obj(cx, SetObject::create(cx));
>      if (!obj)
>          return false;

Likewise.

::: js/src/jsweakmap.cpp
@@ +513,5 @@
>  {
>      CallArgs args = CallArgsFromVp(argc, vp);
>      RootedObject obj(cx, NewBuiltinClassInstance(cx, &WeakMapObject::class_));
>      if (!obj)
>          return false;

Move the obj bits down below ThrowIfNotConstructing as well.

Comment 6

[Pulsebot]

https://hg.mozilla.org/integration/mozilla-inbound/rev/9fe635d3bb9b

Comment 7

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/9fe635d3bb9b

Comment 8

[Florian Scholz (Open Web Docs)]

Developer release notes:
https://developer.mozilla.org/en-US/Firefox/Releases/42#JavaScript

Reference compat updates:
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map#Browser_compatibility
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/WeakMap#Browser_compatibility
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set#Browser_compatibility