test(dgram): expand granular Node parity coverage

[TheHypnoo]

Summary

Expand the granular node:dgram parity suite from 4 broad fixtures to 38 focused fixtures, using current Node, Deno, and Bun compatibility corpora as primary evidence. The suite now preserves 18 passing behaviors and 20 stable Perry differences as diagnostic regression cases.

Changes

• add 34 granular fixtures across validation, lifecycle, connection state, send behavior, socket controls, callback timing, buffer/queue metrics, and ref/unref behavior
• cover advanced socket/address validation, legacy sendto(), DataView and scatter-gather sends, connected range guards, custom lookup, close/dispose and connect ordering, bind conflicts/retries, block lists, DNS error routing, constructor buffer options, send bounds, empty arrays, implicit binding, TTL boundaries, constructor listeners, and callback byte counts
• document current upstream commits and representative Node/Deno/Bun case mappings in test-parity/node-suite/dgram/STATUS.md
• retain 20 deterministic Perry differences, including missing validation, synchronous send callbacks, unsupported scatter-gather/block lists/custom lookup/async disposal, ignored buffer ranges, and return/normalization differences
• ratchet the measured dgram floor to 18/38 while leaving aggregate metadata at its last clean full-suite snapshot
• keep all bound ports ephemeral and loopback-only; exclude reusePort, shared ports, cluster/fd transfer, unguarded IPv6, interface multicast, kernel error paths, and scheduler-sensitive stress/races

Related issue

n/a — standalone parity-suite expansion.

Test plan

NODE_BIN=/tmp/node-v26.5.0/bin/node \
python3 scripts/node_suite_run.py "$PWD/target/release/perry" "$PWD" dgram

module                 pass  total      %
dgram                    18     38   47.4  diff=20
OVERALL node-suite: 18/38 (47.4%)

cargo fmt --all -- --check
./scripts/check_file_size.sh
python3 -m json.tool test-parity/node_suite_baseline.json
git diff --check

• cargo build --release clean (performed by the focused parity wrapper before the fixture-only follow-up)
• cargo test --workspace --exclude perry-ui-ios --exclude perry-ui-tvos --exclude perry-ui-watchos --exclude perry-ui-gtk4 --exclude perry-ui-android --exclude perry-ui-windows passes — not run; no Rust source changed
• Added focused tests under test-parity/node-suite/dgram/
• Documentation updated in the suite-local STATUS.md
• Platform UI build not applicable

Screenshots / output

The focused baseline runner completed with 18 passes, 20 stable output diffs, and no compile_fail, perry_err, or node_err buckets.

Checklist

• I have NOT bumped the workspace version or edited CLAUDE.md / CHANGELOG.md
• My commits follow the repository commit-prefix convention
• I've read CONTRIBUTING.md and agree to the Code of Conduct

Summary by CodeRabbit

• Tests
  • Expanded dgram parity with new UDP socket scripts covering connection state transitions, connect/disconnect ordering, bind/close behavior, abort-signal handling, TTL/setMulticastTTL validation, and buffer/queue metrics.
  • Added send/receive coverage for callback ordering, connected/implicit default host, empty payloads/empty arrays, buffer slices/ranges, message views, sendto/argument validation, error routing, blocklists, and bind conflicts.
• Documentation
  • Expanded the dgram parity status report with fixture counts, deterministic comparison rules, and enumerated behavioral differences.
• Maintenance
  • Updated the dgram baseline thresholds to 18/38.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro Plus

Run ID: 14af7b66-5d48-4180-aa92-4d8108a286a4

📥 Commits

Reviewing files that changed from the base of the PR and between 42cf2b3 and d26023d.

📒 Files selected for processing (1)

• test-parity/node-suite/dgram/lifecycle/bind-error-retry.ts

🚧 Files skipped from review as they are similar to previous changes (1)

• test-parity/node-suite/dgram/lifecycle/bind-error-retry.ts

---

📝 Walkthrough

Walkthrough

Changes

dgram parity coverage

Layer / File(s)	Summary
Fixture scope and baseline test-parity/node-suite/dgram/STATUS.md, test-parity/node_suite_baseline.json	Documents upstream evidence, 38 fixtures, stable differences, exclusions, and verification commands, then raises the dgram baseline from 4/4 to 18/38.
Socket lifecycle and state transitions test-parity/node-suite/dgram/connection/*, test-parity/node-suite/dgram/lifecycle/*, test-parity/node-suite/dgram/metrics/queue-and-ref.ts	Adds coverage for connection ordering and transitions, bind overloads, conflicts and retries, abort signals, disposal and close behavior, custom lookup, queue metrics, and ref state.
Datagram sending behavior test-parity/node-suite/dgram/send/*	Adds send/receive coverage for overloads, connected and default-host sends, empty and multiple datagrams, implicit binding, callback ordering, ranges, listeners, error routing, blocklists, and address defaults.
Socket and send validation test-parity/node-suite/dgram/validation/*	Adds diagnostics for socket options, send and address arguments, connected-send restrictions, message views, scatter payloads, buffer bounds, empty arrays, and sendto() arguments.
Socket metrics and control validation test-parity/node-suite/dgram/control/*, test-parity/node-suite/dgram/metrics/*	Adds validation coverage for TTL, queue metrics, buffer-size operations, and configured socket buffer options.

Estimated code review effort: 3 (Moderate) | ~25 minutes

Possibly related PRs

• PerryTS/perry#5166: Updates parity baseline metadata and module pass-floor thresholds in the same baseline configuration.

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly summarizes the main change: expanded granular Node parity coverage for dgram.
Description check	✅ Passed	The description follows the template and includes summary, changes, issue, test plan, screenshots, and checklist.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch test/expand-node-dgram-parity

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[TheHypnoo]

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[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@test-parity/node-suite/dgram/lifecycle/bind-error-retry.ts`:
- Around line 11-13: Annotate the error callback parameter in the candidate.once
error handler as NodeJS.ErrnoException (or an equivalent type containing code
and syscall) so those properties compile under strict TypeScript settings.
Preserve the existing resolve format and behavior.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro Plus

Run ID: 83c2e1fa-7aa9-456f-b791-cf4269cf9143

📥 Commits

Reviewing files that changed from the base of the PR and between c39a79d and 42cf2b3.

📒 Files selected for processing (10)

• test-parity/node-suite/dgram/STATUS.md
• test-parity/node-suite/dgram/connection/connect-ordering.ts
• test-parity/node-suite/dgram/lifecycle/bind-error-retry.ts
• test-parity/node-suite/dgram/lifecycle/close-ordering.ts
• test-parity/node-suite/dgram/metrics/create-socket-buffer-options.ts
• test-parity/node-suite/dgram/send/empty-array.ts
• test-parity/node-suite/dgram/send/implicit-bind-state.ts
• test-parity/node-suite/dgram/validation/buffer-bounds.ts
• test-parity/node-suite/dgram/validation/message-views.ts
• test-parity/node_suite_baseline.json

🚧 Files skipped from review as they are similar to previous changes (2)

• test-parity/node-suite/dgram/validation/message-views.ts
• test-parity/node_suite_baseline.json