types(populate): retain populated paths in toObject() and toJSON() unless depopulate: true set

[vkarpov15]

Fix #16085

Summary

The populate typing fix now preserves populated path types through toObject() / toJSON() for document, query, and model populate() calls, while still returning the original raw path types for toObject({ depopulate: true }).

The primary change is a new PopulateDocumentResult type that returns a document with overwritten toObject() and toJSON() that accounts for populated paths

Examples

[Copilot]

Pull request overview

This PR updates Mongoose’s TypeScript populate typings so that populated path types are preserved through toObject() / toJSON() (for document, query, and model populate()), while still returning depopulated/raw path types when calling toObject({ depopulate: true }) / toJSON({ depopulate: true }).

Changes:

• Introduces a PopulateDocumentResult helper type that overrides toObject() / toJSON() return types based on whether depopulate: true is set.
• Updates Document.populate(), Document.$assertPopulated(), Model.populate(), and query populate result typing to return PopulateDocumentResult.
• Adds type tests covering populated arrays and depopulate behavior for toObject().

Reviewed changes

Copilot reviewed 1 out of 5 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
types/query.d.ts	Wraps populated query document results in PopulateDocumentResult to preserve populated serialization typings.
types/populate.d.ts	Adds PopulateDocumentResult (+ related helpers) to override toObject() / toJSON() return types based on depopulate.
types/models.d.ts	Updates Model.populate<Paths>() return types to use PopulateDocumentResult.
types/document.d.ts	Updates Document.populate() and $assertPopulated() return types to use PopulateDocumentResult.
test/types/populate.test.ts	Adds compile-time assertions for populated array toObject() and depopulated toObject({ depopulate: true }).

[Copilot]

This hunk adds type assertions for toObject() and toObject({ depopulate: true }) on populated docs, but the PR also changes toJSON() typings. To prevent regressions, add equivalent assertions for toJSON() and toJSON({ depopulate: true }) on these populated results (doc.populate, query.populate, and Model.populate cases).