⚡ Bolt: Optimize yEnc decoding latency using C-backed translations

[xbmc4lyfe]

💡 What: Replace manual byte-by-byte iteration in _decode_yenc_lines with C-backed bytearray.translate and bytearray.find operations.
🎯 Why: Python-level iteration over byte streams with arithmetic operations is extremely slow, acting as a major performance bottleneck during the validation of large downloaded article bodies.
📊 Impact: The decoding time for typical payloads is reduced from ~3.4 seconds to ~0.17 seconds (approximately a 20x improvement).
🔬 Measurement: Verified using an internal 10k line benchmark script (benchmark.py) and validated that the full test suite remains green.

---

PR created automatically by Jules for task 3636230887511374629 started by @xbmc4lyfe

[google-labs-jules]

👋 Jules, reporting for duty! I'm here to lend a hand with this pull request.

When you start a review, I'll add a 👀 emoji to each comment to let you know I've read it. I'll focus on feedback directed at me and will do my best to stay out of conversations between you and other bots or reviewers to keep the noise down.

I'll push a commit with your requested changes shortly after. Please note there might be a delay between these steps, but rest assured I'm on the job!

For more direct control, you can switch me to Reactive Mode. When this mode is on, I will only act on comments where you specifically mention me with @jules. You can find this option in the Pull Request section of your global Jules UI settings. You can always switch back!

New to Jules? Learn more at jules.google/docs.

---

For security, I will only act on instructions from the user who triggered this task.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro Plus

Run ID: f7e5be2b-d624-4af8-a169-311dffbf4b08

📥 Commits

Reviewing files that changed from the base of the PR and between 0de7ede and dd6f194.

📒 Files selected for processing (1)

• verify_nzb.py

📜 Recent review details

🔇 Additional comments (2)

verify_nzb.py (2)

118-123: LGTM!

---

125-147: LGTM!

---

📝 Walkthrough

Summary by CodeRabbit

• Performance
  • Optimized yEnc decoding for faster processing speeds while maintaining the same functionality and validation behavior.

Walkthrough

This PR optimizes yEnc line decoding in verify_nzb.py by replacing a sequential byte-by-byte loop with precomputed translation tables and bulk-translation logic. The new implementation scans for escape-byte positions, translates unescaped segments in bulk, and handles escaped bytes selectively, while preserving all validation behavior.

Changes

yEnc Decoding Optimization

Layer / File(s)	Summary
yEnc line decoding with precomputed translation tables verify_nzb.py	Introduces _YENC_DECODE_TABLE and _YENC_ESCAPE_TABLE precomputed translation tables and rewrites _decode_yenc_lines to bulk-translate unescaped byte ranges via bytes.translate() and handle escaped bytes by scanning for = positions, while preserving dangling-escape validation.

Estimated code review effort

🎯 4 (Complex) | ⏱️ ~45 minutes

Poem

🐰 A table-powered yEnc decode,
Bulk translation lightens the load,
Escapes scanned with care,
No dangling bytes bare,
Faster bytes down the information road! 🚀

🚥 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 directly and clearly describes the main optimization: replacing the yEnc decoding implementation with a C-backed translation approach for performance improvement.
Description check	✅ Passed	The description is directly related to the changeset, explaining the what, why, and measured impact of the yEnc decoding optimization in the pull request.
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.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ 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 bolt-yenc-opt-3636230887511374629

✨ Simplify code

• Create PR with simplified code
• Commit simplified code in branch bolt-yenc-opt-3636230887511374629

Warning

Billing warning: we have not been able to collect payment for this subscription for more than 72 hours. Please update the payment method or pay any pending invoices in Billing to avoid service interruption.

---

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