fix(NODE-7436): EJSON.stringify type signature

[chdanielmueller]

Description

Summary of Changes

This pull request enhances the flexibility and robustness of the EJSON.stringify function by supporting multiple parameter signature combinations, similar to JSON.stringify.
It introduces a new internal type guard to accurately distinguish between options and replacer parameters, and adds comprehensive tests to ensure correct behavior across all supported overloads.
It supports a previously advertised function signature which was not implemented. EJSON.stringify(object, { relaxed: false }, 2)

Notes for Reviewers

The tests should contain every previously possible and also previously advertised but not working combination of inputs.
The changes within the function have to do with the previous typescript signature which has been used but did not work. See

js-bson/test/bench/etc/generate_documents.ts

Line 27 in 0712bb1

bson.EJSON.stringify(singleField, { relaxed: false }, 2)

Off Topic: Documented within NODE-7437

I noticed that the array replacement signature for JSON.stringify replaces the serialized keys.

const testDoc = {
  objectId: ObjectId.createFromHexString('111111111111111111111111')
};

const result = EJSON.stringify(testDoc, ['objectId', '$oid']) // {"objectId":{"$oid":"111111111111111111111111"}}
const result2 = EJSON.stringify(testDoc, ['objectId']) // {"objectId":{}}

Maybe if the replacer is an Array it should add the data types to the array.

Release Highlight

EJSON.stringify now correctly handles all parameter combinations

Previously, calling EJSON.stringify(value, options, space) silently discarded the space parameter, producing unformatted output. This has been fixed so all documented call signatures work as expected:

// This now correctly produces indented canonical EJSON
EJSON.stringify(doc, { relaxed: false }, 2);

Thanks to @chdanielmueller for working on this problem!

Double check the following

• Lint is passing (npm run check:lint)
• Self-review completed using the steps outlined here
• PR title follows the correct format: type(NODE-xxxx)[!]: description
  • Example: feat(NODE-1234)!: rewriting everything in coffeescript
• Changes are covered by tests
• New TODOs have a related JIRA ticket

[PavelSafronov]

@chdanielmueller , thanks so much for your contribution! The team is going to prioritize this PR and NODE-7436 at our next triage session.

[tadjik1]

hi @chdanielmueller, thanks a lot for the contribution. The bug is real, well-documented, and the test coverage you added is great.
The core issue is that space = 0 discards the user's space value when options are passed in the replacer position.

However, the fix is significantly more complex than it needs to be. The entire bug can be fixed by deleting one line (space = 0). The existing code already treats any non-array object in replacer position as options.

I would suggest minimal fix:

if (replacer != null && typeof replacer === 'object' && !Array.isArray(replacer)) {
  options = replacer;
  replacer = undefined;
- space = 0
}

The overloads, type guard, and restructured function body are unnecessary for this fix and introduce maintenance overhead.

[Copilot]

Pull request overview

This PR updates EJSON.stringify to support additional call signatures (notably (value, options, space)), aligning its ergonomics more closely with JSON.stringify, and adds tests to validate supported overload combinations.

Changes:

• Added overloads and new runtime argument-disambiguation logic for EJSON.stringify.
• Introduced an internal type guard used to distinguish options from replacer/space.
• Added a new test suite covering many parameter signature combinations.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
src/extended_json.ts	Adds overloads and new argument parsing for EJSON.stringify via an internal options type guard.
test/node/extended_json.test.ts	Adds test coverage for supported EJSON.stringify parameter combinations.

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[chdanielmueller]

Hi @tadjik1
Thank you for the feedback and the review. I did address all your comments with the new changes with one exception: #870 (comment)
Giving it back to you for another review 😄

[tadjik1]

hi @chdanielmueller, thanks a lot for updating PR 👍 Just wanted to confirm that this work is not lost, and it's tracked. I will re-review changes as soon as possible.

[PavelSafronov]

Changes look good, thanks for this!