Add PNG benchmarks

[Shane32]

Summary by CodeRabbit

• Tests
  • Added performance benchmarks for PNG byte QR code rendering across multiple QR sizes (small to huge).
  • Includes memory diagnostics to track allocation and performance over time.
  • No impact on runtime behavior or user-facing features.

[coderabbitai]

📝 Walkthrough

Walkthrough

Adds a new BenchmarkDotNet benchmark class to measure PNG byte QR code rendering by pre-generating QRCodeData samples (small/medium/big) and exposing four benchmark methods calling GetGraphic with different pixel sizes.

Changes

Cohort / File(s)	Summary of changes
Benchmarks QRCoderBenchmarks/PngByteQRCode.cs	Introduces PngByteQRCodeBenchmark with MemoryDiagnoser, prebuilt QRCodeData samples via QRCodeGenerator (ECC L), and four public benchmark methods: Small/Medium/Big (GetGraphic(10)) and Huge (GetGraphic(50)).

Sequence Diagram(s)

sequenceDiagram
  autonumber
  participant BDN as BenchmarkDotNet
  participant PB as PngByteQRCodeBenchmark
  participant G as QRCodeGenerator
  participant P as PngByteQRCode

  Note over PB: Construction/Setup
  BDN->>PB: Instantiate benchmark class
  PB->>G: CreateQrCode("small", ECC L)
  PB->>G: CreateQrCode("medium", ECC L)
  PB->>G: CreateQrCode("big", ECC L)
  G-->>PB: QRCodeData instances

  rect rgba(220,240,255,0.6)
  Note over BDN,PB: Benchmark iteration (example: Small)
  BDN->>PB: RenderPngByteQRCodeSmall()
  PB->>P: new PngByteQRCode(smallData)
  P->>P: GetGraphic(10)
  P-->>PB: byte[] PNG
  PB-->>BDN: result
  end

  rect rgba(240,255,220,0.6)
  Note over BDN,PB: Other cases
  BDN->>PB: RenderPngByteQRCodeMedium/Big/Huge()
  PB->>P: new PngByteQRCode(med/big)
  P->>P: GetGraphic(10 or 50)
  P-->>PB: byte[] PNG
  PB-->>BDN: result
  end

Loading

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

Pre-merge checks and finishing touches

❌ 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%.	You can run @coderabbitai generate docstrings to improve docstring coverage.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title Check	✅ Passed	The title clearly and succinctly summarizes the main change of introducing PNG benchmarks without extraneous detail or vague phrasing, making it immediately understandable to reviewers and maintainers.

✨ Finishing touches

• 📝 Generate Docstrings

🧪 Generate unit tests

• Create PR with unit tests
• Post copyable unit tests in a comment
• Commit unit tests in branch add_png_benchmarks

---

📜 Recent review details

Configuration used: CodeRabbit UI

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between ec52e48 and fcaca92.

📒 Files selected for processing (1)

• QRCoderBenchmarks/PngByteQRCode.cs (1 hunks)

🧰 Additional context used

🧬 Code graph analysis (1)

QRCoderBenchmarks/PngByteQRCode.cs (1)

QRCoder/QRCodeGenerator.cs (1)

• ECCLevel (266-274)

⏰ Context from checks skipped due to timeout of 90000ms. You can increase the timeout in your CodeRabbit configuration to a maximum of 15 minutes (900000ms). (1)

• GitHub Check: build

🔇 Additional comments (5)

QRCoderBenchmarks/PngByteQRCode.cs (5)

11-20: LGTM! Benchmark setup follows best practices.

Pre-generating QRCodeData samples in the constructor ensures the benchmarks measure only rendering performance, not generation time. The sample sizes (small, medium, big) provide good coverage for performance testing.

---

23-28: LGTM!

The benchmark correctly measures rendering of a small QR code with pixel size 10.

---

30-35: LGTM!

The benchmark correctly measures rendering of a medium-sized QR code with pixel size 10.

---

37-42: LGTM!

The benchmark correctly measures rendering of a big QR code with pixel size 10.

---

44-49: LGTM!

The "Huge" benchmark correctly measures rendering performance with a larger pixel size (50 vs 10), providing insight into how scaling affects performance.

---

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

• X
• Mastodon
• Reddit
• LinkedIn

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