Deprecated warning with nan v2.7.0 and Node.js 9.0.0

[fivdi]

When a native module using nan v2.7.0 is installed with Node.js 9.0.0 there is a deprecated warning. For example, here's the warning shown when installing the epoll module:

pi@raspberrypi:~/epoll $ npm i epoll

> epoll@1.0.0 install /home/pi/epoll/node_modules/epoll
> node-gyp rebuild

make: Entering directory '/home/pi/epoll/node_modules/epoll/build'
  CXX(target) Release/obj.target/epoll/src/epoll.o
In file included from ../../nan/nan.h:192:0,
                 from ../src/epoll.cc:15:
../../nan/nan_maybe_43_inl.h: In function ‘Nan::Maybe<bool> Nan::ForceSet(v8::Local<v8::Object>, v8::Local<v8::Value>, v8::Local<v8::Value>, v8::PropertyAttribute)’:
../../nan/nan_maybe_43_inl.h:112:73: warning: ‘v8::Maybe<bool> v8::Object::ForceSet(v8::Local<v8::Context>, v8::Local<v8::Value>, v8::Local<v8::Value>, v8::PropertyAttribute)’ is deprecated: Use CreateDataProperty / DefineOwnProperty [-Wdeprecated-declarations]
   return obj->ForceSet(isolate->GetCurrentContext(), key, value, attribs);
                                                                         ^
In file included from /home/pi/.node-gyp/9.0.0/include/node/v8.h:26:0,
                 from ../src/epoll.cc:11:
/home/pi/.node-gyp/9.0.0/include/node/v8.h:3115:29: note: declared here
                 Maybe<bool> ForceSet(Local<Context> context, Local<Value> key,
                             ^
/home/pi/.node-gyp/9.0.0/include/node/v8config.h:318:3: note: in definition of macro ‘V8_DEPRECATED’
   declarator __attribute__((deprecated(message)))
   ^~~~~~~~~~
  SOLINK_MODULE(target) Release/obj.target/epoll.node
  COPY Release/epoll.node
make: Leaving directory '/home/pi/epoll/node_modules/epoll/build'
npm WARN saveError ENOENT: no such file or directory, open '/home/pi/epoll/package.json'
npm notice created a lockfile as package-lock.json. You should commit this file.
npm WARN enoent ENOENT: no such file or directory, open '/home/pi/epoll/package.json'
npm WARN epoll No description
npm WARN epoll No repository field.
npm WARN epoll No README data
npm WARN epoll No license field.

+ epoll@1.0.0
added 3 packages in 10.643s
pi@raspberrypi:~/epoll $ 

[kkoopa]

That is unfortunate. It was only a question of time. ForceSet has been on its way out in V8 for a long time, but if I remember correctly there is no proper alternative, so the fix is not straightforward, if at all possible. Neither CreateDataProperty not DefineOwnProperty offer the same semantics.
Related: #504

[fivdi]

If I understand PR #708 correctly, the plan is leave Nan::ForceSet as it is, mark it as deprecated and introduce Nan::DefineOwnProperty.

V8 already has v8::Object::ForceSet marked as deprecated. This results in the deprecation warning shown in the above post irrespective of whether Nan::ForceSet is used by an addon or not.

So if I want to suppress the V8 deprecation warning for v8::Object::ForceSet I'll have to suppress it in my addon because NAN will not be suppressing it, is this correct?

[bnoordhuis]

@fivdi Yes, correct.

[kkoopa]

Still accounting for versions. Nan::ForceSet would be marked as deprecated regardless of Node version, but for Node 9 onwards, Nan::ForceSet would be an alias for Nan::DefineOwnProperty. That should not cause any undue warnings.

…

On November 4, 2017 8:31:17 AM GMT+02:00, Brian Cooke ***@***.***> wrote: If I understand PR #708 correctly, the plan is leave Nan::ForceSet as it is, mark it as deprecated and introduce Nan::DefineOwnProperty. V8 already has v8::Object::ForceSet marked as deprecated. This results in the deprecation warning shown in the above post irrespective of whether Nan::ForceSet is used by an addon or not. So if I want to suppress the V8 deprecation warning for v8::Object::ForceSet I'll have to suppress it in my addon because NAN will not be suppressing it, is this correct?

[kkoopa]

Fixed in master. New release coming soon.