Add usePushEach flag to Mongoose Schema Options

[stieg]

In order for devs to be able to work around the issues described in
Automattic/mongoose#5574 we need to be able
to supply the usePushEach flag to the Mongoose SchemaOptions. This
options functionality is described in
Automattic/mongoose#4455 and is required for
anyone who modifies arrays inline who is using Mongoose 4 and MongoDB
3.6+

Testing:
Copied changes to local project and verified compilation worked.

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[typescript-bot]

@stieg Thank you for submitting this PR!

🔔 @simonxca @horiuchi @sindrenm @lukasz-zak - please review this PR in the next few days. Be sure to explicitly select Approve or Request Changes in the GitHub UI so I know what's going on.

If no reviewer appears after a week, a DefinitelyTyped maintainer will review the PR instead.

[simonbear89]

@stieg Thanks! LGTM.

[typescript-bot]

A definition author has approved this PR ⭐️. A maintainer will merge this PR shortly. If it shouldn't be merged yet, please leave a comment saying so and we'll wait. Thank you for your contribution to DefinitelyTyped!

[EtienneBoutet]

Did the option been added ? It's not there in 5.0.16..

[stieg]

Hrmm... Option was added in commit d512b1f but seems to have been removed in commit ccdc539 by Art a.molcanovas@gmail.com. Maintainers... know whats up with this? This because of mongoose 5 and this feature may be unnecessary now (my best guess)?

[EtienneBoutet]

The problem still exists with Mongoose (¢pushAll).. I did another PR for this and they added it.. Do you know any work around if they decide to remove it once again ?

[stieg]

@EtienneBoutet I simply did a type assertion to work around the issue when defining my Schema Options. Something like this was my workaround

const MySchema = new Schema({
   ...
}, {
   timestamps: true,
   usePushEach: true,
} as SchemaOptions);

[EtienneBoutet]

Thanks a lot ! 👍