Accept JSON encoder keyword arguments and normalize initial indentation by youknowdot · Pull Request #9459 · RustPython/RustPython

youknowdot · 2026-10-29T12:57:52Z

Summary

Accept the nine CPython keyword names in _json.make_encoder and obj / _current_indent_level in encoder calls, while preserving positional arguments.
Treat a negative initial indentation level as zero before entering recursive encoding, matching the empty prefix produced by CPython's negative string repetition.
Retire the sole local marker in the whole test_json/test_speedups.py through scripts/update_lib from the pinned CPython source.

CPython basis

Pinned source: d220409a13b77de7a6c30abe16ea90db01528edc.

The integer digit-limit work in #8087 is independent and is not duplicated here. Generic argument-binding error wording and inherited constructor validation precedence are not changed.

Verification

Scoped check and strict Clippy passed. A bounded CLI build timed out during code generation; the same command then completed successfully using its cached dependencies. The resulting protected binary passed:

Ten ordinary canonical test_speedups methods in both RustPython and pinned CPython, with zero failures, errors, skips or expected failures.
Twenty finite records matched CPython byte-for-byte, covering nested output, keyword/mixed construction and calls, negative/zero/positive initial levels, rejected duplicate/missing/unknown arguments, and __index__ callbacks.
The complete test module was refreshed using scripts/update_lib migrate; its bytes match the pinned canonical source used by validation.

Validation used base 95bf39a54b67df408db9da53cfc546e711c93895. The branch was subsequently fast-forwarded to bcaa07a7d843c2a027bfb5773b56f1b8601ca33b, whose two deque-related files do not overlap this change. The tested native source is byte-identical after that integration and normal commit hooks passed. No new runtime pass is claimed for that final base; current-head CI remains required.

The two explicit GC/mutation tests in the module were excluded from local execution. Full workspace/C-API suites, concurrency/GC/stress tests and extreme allocation cases were not run. Generic binder error wording and inherited constructor validation precedence are outside this patch.

AI assistance: OpenAI Codex (model version unavailable).

Summary by CodeRabbit

Bug Fixes
- JSON encoding now treats negative indentation levels as zero, preventing them from producing invalid indentation behavior. Nonnegative indentation settings continue to work as before, so existing formatting choices remain unchanged. This update affects the output only when a negative indentation level is provided; it does not change the available JSON encoding options or the values used for other settings.

Match CPython encoder_new/encoder_call keyword names and negative initial indentation prefix behavior. Refresh the complete speedups test module through update_lib after scoped canonical and oracle validation. Assisted-by: OpenAI Codex: model version unavailable

coderabbitai · 2026-10-29T12:58:00Z

No actionable comments were generated in the recent review.

Recent review info

Run configuration

Source mode: Auto
Repository: RustPython/RustPython
Branch: main
File: .coderabbit.yml
Commit: bcaa07a
Layers: Repository YAML
Review profile: CHILL
Plan: Advanced
Run ID: fbc3b5a6-3636-4017-b5aa-e8a3bd43a09f

Commits

Reviewing files that changed from the base of the PR and between bcaa07a and 3ec2193.

Files ignored due to path filters: 1

Lib/test/test_json/test_speedups.py is excluded by !Lib/**

Files selected for processing: 1

crates/stdlib/src/json.rs

Included review availability: This review used your included allowance. Your plan provides up to 10 included reviews per hour; 8 remain after this review.

Walkthrough

The JSON encoder constructor and call method now receive argument structs instead of nested tuples. The call method also clamps negative indent values to zero before encoding.

Changes: JSON Encoder

Layer / File(s)	Summary
Use structs for encoder arguments `crates/stdlib/src/json.rs`	The constructor and call method use argument structs. The call method clamps negative indent values to zero before encoding.

Priority: Normal

Estimated code review effort: 2 (Simple) | ~8 minutes

Change: Bug fix

Suggested reviewers: youknowone

Merge Risk: Minimal · up to 3ec21

The encoder changes support the expected keyword arguments while preserving positional calls. No actionable merge-blocking issue was identified; current-head CI should pass before merging.

Pre-merge checks: 4 · 1

Failed checks: 1 warning

Check name	Status	Explanation	Resolution
Docstring Coverage		Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff with cyclomatic complexity of at least 2. Documentat…	Write docstrings for the functions missing them to satisfy the coverage threshold.

Passed checks: 4 passed

Check name	Status	Explanation
Description Check		Check skipped - CodeRabbit’s high-level summary is enabled.
Title check		The title names two changes that the changeset contains: accepting JSON encoder keyword arguments (EncoderArgs and EncoderCallArgs structs replace tuples, with the CPython keyword names) and normalizi…
Linked Issues check		Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check		Check skipped because no linked issues were found for this pull request.

Full details: Title check

Explanation

The title names two changes that the changeset contains: accepting JSON encoder keyword arguments (EncoderArgs and EncoderCallArgs structs replace tuples, with the CPython keyword names) and normalizing the initial indentation (negative indent levels are clamped to zero). The title is specific and matches the primary change in crates/stdlib/src/json.rs. It is slightly long at 71 characters, but it is clear and not vague.

Full details: Docstring Coverage

Explanation

Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff with cyclomatic complexity of at least 2. Documentation-only edits and deletions within surviving functions are included; unchanged diff context and fully deleted functions are excluded. Analyzed 2 functions across 1 files.

Resolution

Write docstrings for the functions missing them to satisfy the coverage threshold.

Finishing Touches

🧪 Generate unit tests (beta)

Create a new PR

Autofix · Keep fixing CodeRabbit findings and required CI, and resolving merge conflicts

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

_{Comment @coderabbitai help to get the list of available commands.}

github-actions · 2026-10-29T12:58:58Z

📦 Library Dependencies

The following Lib/ modules were modified. Here are their dependencies:

[x] lib: cpython/Lib/json
[ ] test: cpython/Lib/test/test_json (TODO: 1)

dependencies:

json

dependent tests: (21 tests)

json: test_embed test_interpreters test_json test_logging test_plistlib test_profiling test_pydoc test_pyrepl test_remote_pdb test_subprocess test_sysconfig test_tomllib test_tools test_traceback test_zoneinfo
- importlib.metadata: test_importlib
- multiprocessing.resource_tracker: test_concurrent_futures
- pdb: test_pdb
- profiling: test_profiling
  - cProfile: test_free_threading test_pstats

Legend:

[+] path exists in CPython
[x] up-to-date, [ ] outdated

chatgpt-codex-connector · 2026-10-29T13:07:05Z

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	⚠️ Failed 2026-10-29T13:08:28.128472Z We couldn’t complete this review. Comment `@codex review` to try again.	`3ec2193`	Draft marked ready

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

Open a pull request for review
Mark a draft as ready
Comment "@codex review" or "@codex security review".

Codex reacts with 👀 while any review is running, comments if it has suggestions, and reacts with 👍 once all reviews finish with no findings.

codspeed · 2026-10-29T13:23:26Z

Merging this PR will not alter performance

✅ 62 untouched benchmarks
⏩ 4 skipped benchmarks¹

_{Comparing youknowdot:fix/json-indent-315-20261029 (3ec2193) with main (bcaa07a)}

4 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

youknowone approved these changes Oct 29, 2026

View reviewed changes

youknowone marked this pull request as ready for review October 29, 2026 13:06

youknowone enabled auto-merge (squash) October 29, 2026 13:06

youknowone merged commit d24ca41 into RustPython:main Oct 29, 2026
22 checks passed

Navigation Menu

Repository navigation

Accept JSON encoder keyword arguments and normalize initial indentation - #9459

Accept JSON encoder keyword arguments and normalize initial indentation#9459
youknowone merged 1 commit into
RustPython:mainfrom
youknowdot:fix/json-indent-315-20261029

youknowdot commented Oct 29, 2026 •

edited by coderabbitai Bot

Loading

Uh oh!

coderabbitai Bot commented Oct 29, 2026 •

edited

Loading

Uh oh!

github-actions Bot commented Oct 29, 2026

Uh oh!

chatgpt-codex-connector Bot commented Oct 29, 2026 •

edited

Loading

Uh oh!

codspeed Bot commented Oct 29, 2026

Uh oh!

Uh oh!

Reviewers

Uh oh!

Assignees

Labels

Projects

Milestone

Development

Uh oh!

3 participants

Conversation

youknowdot commented Oct 29, 2026 • edited by coderabbitai Bot Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Summary

CPython basis

Verification

Summary by CodeRabbit

Uh oh!

coderabbitai Bot commented Oct 29, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

github-actions Bot commented Oct 29, 2026

📦 Library Dependencies

Uh oh!

chatgpt-codex-connector Bot commented Oct 29, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Codex Review Summary

Uh oh!

codspeed Bot commented Oct 29, 2026

Merging this PR will not alter performance

Footnotes

Uh oh!

Uh oh!

Reviewers

Uh oh!

Assignees

Labels

Projects

Milestone

Development

Uh oh!

3 participants

youknowdot commented Oct 29, 2026 •

edited by coderabbitai Bot

Loading

coderabbitai Bot commented Oct 29, 2026 •

edited

Loading

chatgpt-codex-connector Bot commented Oct 29, 2026 •

edited

Loading