Estou pegando um erro de $pushAll

Programação Node.js
#1 
const express = require('express');

const authMiddleware = require(’…/middlewares/auth’);

const Project = require(’…/models/Project’);
const Task = require(’…/models/Task’);

const router = express.Router();

router.use(authMiddleware);

router.get(’/’, async (req, res) => {
try {
const projects = await Project.find().populate([‘user’, ‘tasks’]);

return res.send({ projects });

} catch (err) {
return res.status(400).send({ error: ‘Erro ao carregar o projeto’ });
}
});

router.get(’/:projectId’, async (req, res) => {
try {
const project = await Project.findById(req.params.projectId).populate([‘user’, ‘tasks’]);

return res.send({ project });

} catch (err) {
return res.status(400).send({ error: ‘Error loading project’ });
}
});

router.post(’/’, async (req, res) => {
try {
const { title, description, tasks } = req.body;

const project = await Project.create({ title, description, user: req.userId });

await Promise.all(tasks.map(async task => {
  const projectTask = new Task({ ...task, project: project._id });

  await projectTask.save();

  project.tasks.push(projectTask);
}));

await project.save();

return res.send({ project });

} catch (err) {
console.log(err)
return res.status(400).send({ error: ‘Erro ao criar o projeto’ });
}
});

router.put(’/:projectId’, async (req, res) => {
try {
const { title, description, tasks } = req.body;

const project = await Project.findByIdAndUpdate(req.params.projectId, {
  title,
  description
}, { new: true });

project.tasks = [];
await Task.remove({ project: project._id });

await Promise.all(tasks.map(async task => {
  const projectTask = new Task({ ...task, project: project._id });

  await projectTask.save();

  project.tasks.push(projectTask);
}));

await project.save();

return res.send({ project });

} catch (err) {
return res.status(400).send({ error: ‘Error updating project’ });
}
});

router.delete(’/:projectId’, async (req, res) => {
try {
await Project.findByIdAndRemove(req.params.projectId);

return res.send();

} catch (err) {
return res.status(400).send({ error: ‘Error deleting project’ });
}
});

module.exports = app => app.use(’/projects’, router);

[2/4] Fetching packages…
[3/4] Linking dependencies…
[4/4] Building fresh packages…
success Saved lockfile.
Done in 30.90s.
PS C:\Users\paula\projetos\apiNode\src> yarn add mongoose
yarn add v1.3.2
[1/4] Resolving packages…
[2/4] Fetching packages…
[3/4] Linking dependencies…
[4/4] Building fresh packages…
success Saved lockfile.
success Saved 0 new dependencies.
Done in 3.15s.
PS C:\Users\paula\projetos\apiNode\src> node index.js
{ MongoError: Unknown modifier: $pushAll
at Function.MongoError.create (C:\Users\paula\projetos\apiNode\node_modules\mongodb-core\lib\error.js:31:11)
at toError (C:\Users\paula\projetos\apiNode\node_modules\mongodb\lib\utils.js:139:22)
at C:\Users\paula\projetos\apiNode\node_modules\mongodb\lib\collection.js:1059:67
at C:\Users\paula\projetos\apiNode\node_modules\mongodb-core\lib\connection\pool.js:469:18
at _combinedTickCallback (internal/process/next_tick.js:131:7)
at process._tickCallback (internal/process/next_tick.js:180:9)
name: ‘MongoError’,
message: ‘Unknown modifier: $pushAll’,
driver: true,
index: 0,
code: 9,

#2

Anotando isto resolve:

{
usePushEach: true
},