types: allow arbitrary keys in query filters again

[vkarpov15]

Revert #14764
Fix #14863
Fix #14862

Summary

#14764 introduced issues for quite a few devs, see #14863. We should revert for now, and consider adding #14764 in 9.0.

cc @alex-statsig

Examples

[alex-statsig]

Sorry, sounds good to me! Waiting for 9.0 to make it a breaking change seems reasonable. Guess we could even expose a "typesafe" or "unsafe" version of each function to allow people to opt out, although unsafe is the same as just doing model.query(queryObj as any), so maybe thats a simpler workaround in 9.0

[vkarpov15]

@alex-statsig there's also another issue that popped up in #14842: Mongoose discriminators support specifying the discriminator key in the query filter, and Mongoose will infer the schema based on the discriminator key. For example:

const Person = new Schema({ name: String });
const Employee = Person.discriminator('Employee', new Schema({ title: String }));

// Because discriminator key `__t` is set, Mongoose is able to infer the type of the `title` property, even
// though the model is `Person` not `Employee`
await Person.findOne({ __t: 'Employee', title: 'CEO' });

Is there a way to support this with TypeScript? I imagine we would need some way of defining what discriminators are tied to a particular model in TS.

[hasezoey]

Looks good, lets wait for 9.0 to re-consider introducing this strictness

[hasezoey]

after the revert, does the "expectError" now fail?

[vkarpov15]

Yes. Functions match "object with any keys" in TypeScript, and telling TypeScript "this parameter can be any non-function object" is tricky, I haven't been able to figure out how to do that.

I would love to keep the "this parameter can't be a function" behavior, but not sure how that would work