includeResultMetadata types not changing return type?

[simllll]

Prerequisites

• I have written a descriptive issue title
• I have searched existing issues to ensure the bug has not already been reported

Mongoose version

8.1.1

Node.js version

20.x

MongoDB server version

6.x

Typescript version (if applicable)

5.1.6

Description

I tried upgrading to mongoose 8.x and changed rawResult: true to includeResultMetadata: true, but now typescript complains:

TS2339: Property value does not exist on type
FlattenMaps<IDBJobField> & Required<{   _id: ObjectId; }>

also it seems that the retutrn type is not changed depending on the value of includeResultMetadata

it's the same as in the screenshot, regardless of this flag.

Furthermore; i found it kinda confusing with the mongodb docs, as they say that includeResultMetadata is true by default. Does mongoose set it to false then by default? Or is it actually true, but mongoose just returns the document and strips the rest away? Which would sound to me of a waste of some extra bytes?

error TS2339: Property 'value' does not exist on type 'FlattenMaps & Required<{ _id: ObjectId; }>'.
error TS2339: Property 'lastErrorObject' does not exist on type 'FlattenMaps & Required<{ _id: ObjectId; }>'.
error TS2339: Property 'value' does not exist on type 'FlattenMaps & Required<{ _id: ObjectId; }>'.

Steps to Reproduce

use an example query for findOneAndupdate and play around with the includeResultMetadata flag

Expected Behavior

should return the "ModifyResult" instead, like it did with rawResult: true

[vkarpov15]

Where in the docs do you see that includeResultMetadata is true by default? I think that changed in MongoDB Node driver 6.

Also, is the error just in your IDE or also in TypeScript? Because I'm unable to repro with TypeScript, the following script compiles fine:

import mongoose from 'mongoose';

run();

async function run() {
  const TestModel = mongoose.model('Test', new mongoose.Schema({ name: String }));
  const doc = await TestModel.findOneAndUpdate({}, { name: 'bar' }, { includeResultMetadata: true });
  doc.value;
}

$ ./node_modules/.bin/tsc --strict gh-14303.ts 
$ 

[simllll]

Where in the docs do you see that includeResultMetadata is true by default? I think that changed in MongoDB Node driver 6.

see here:
https://github.com/mongodb/node-mongodb-native/releases/tag/v5.7.0

This option defaults to true, which will return a ModifyResult type. When set to false, which will

and here https://www.mongodb.com/blog/post/behavioral-changes-find-one-family-apis-node-js-driver-6-0-0

Starting with the Node.js Driver 5.7.0 release a new FindOneAndOptions property called includeResultMetadata has been introduced. When this property is set to false (default is true) the findOneAnd APIs will return the requested document as expected.

Also, is the error just in your IDE or also in TypeScript? Because I'm unable to repro with TypeScript, the following script compiles fine:

I will look into it again late,r but it was a build issue, not just an IDE issue. But some other issues are even valid, I had returnDocument: 'after' in some updateOne queries, which makes no sense of course ;)

[simllll]

Regarding includeResultMetadata,
you are right, it's mentionted here that it will be set to false. https://github.com/mongodb/node-mongodb-native/releases/tag/v6.0.0

Once 6.0.0 is released, includeResultMetadata: false will become the default behavior. If your application relies on the previous behavior of these APIs, setting includeResultMetadata: true will allow you to continue to access the ModifyResult directly.

so this should be safe, it wsa just kinda of confusing ;-)

regarding the typescript issue, I iwll look into this now

[simllll]

Alright, I found the issue. It's about the "lean" flag.

import mongoose from 'mongoose';

run();

async function run() {
  const TestModel = mongoose.model('Test', new mongoose.Schema({ name: String }));
  const doc = await TestModel.findOneAndUpdate({}, { name: 'bar' }, { includeResultMetadata: true, lean: true, returnDocument: 'after' });
  doc.value;
}

the problem pops up when I add lean: true to the options. then the returned type definitoin is the one I mentioned.

This brings me to another followup question: If we set includeResultMetadata to true, is mongoose then populating stuff and returns a mongoose document, or does it actually return the raw result like with lean: true?
Because the type of includeResultMetadta: false is the exact same as the ".value" prop when I set it to true...
I would expect it to be the lean version, as this was the behaviour with "rawResult" before. But to be explicit about that, what happens then if I set lean explicity to false?

[vkarpov15]

This brings me to another followup question: If we set includeResultMetadata to true, is mongoose then populating stuff and returns a mongoose document, or does it actually return the raw result like with lean: true? If lean is false, then Mongoose will fully hydrate the document, and .value will contain the fully hydrated document.

I would expect it to be the lean version, as this was the behaviour with "rawResult" before. But to be explicit about that, what happens then if I set lean explicity to false? Setting lean: false is the same as not setting lean at all in this case.