Refactor: consolidate test helpers, parameterize tests, and fix WASM OOM bug

[nao1215]

Summary

• Consolidate duplicated test helpers into tests/common/mod.rs: tiny_png(), send_signed_get(), status_code(), eliminating ~200 lines of duplication across S3/GCS/Azure integration tests
• Parameterize HEAD request tests using rstest, replacing 4 nearly identical test functions with a single parameterized test
• Remove unnecessary .clone() in auth.rs parse_query_params by using contains_key before insert
• Fix misplaced doc comment for tiny_png / large_png_bytes in tests/common/mod.rs
• Fix WASM OOM bug: add #[serde(skip_serializing)] to WasmTransformResponse.bytes to prevent serializing megabytes of image data as a JSON number array, which caused browser hangs when drag-and-dropping images on GitHub Pages

Test plan

• cargo fmt --all -- --check passes
• cargo clippy --all-targets --all-features -- -D warnings passes
• cargo test passes
• Verified WASM build is unaffected (JS accesses bytes via wasm-bindgen getter, not JSON)

Summary by CodeRabbit

• Bug Fixes

  • Improved query parameter validation to explicitly reject duplicate parameters with HTTP 400 Bad Request responses.

• Improvements

  • Optimized WASM response serialization by excluding binary bytes from JSON payloads, reducing message size.

• Tests

  • Refactored test utilities into a shared module to reduce duplication across integration tests.

[coderabbitai]

Caution

Review failed

Pull request was closed or merged during review

📝 Walkthrough

Walkthrough

The PR adds test infrastructure improvements by introducing rstest-based parameterized testing, consolidating test utilities into a shared common module, refactoring integration tests to reduce duplication, fixing duplicate query parameter handling in auth parsing, and excluding large binary data from JSON serialization in WASM responses.

Changes

Cohort / File(s)	Summary
Dependencies & Test Framework Cargo.toml, tests/server_head.rs	Added rstest dev-dependency and refactored HEAD request tests to use rstest parameterization, replacing four individual test functions with a single parameterized test covering all cases.
Test Utilities Consolidation tests/common/mod.rs, tests/azure_integration.rs, tests/gcs_integration.rs, tests/s3_integration.rs	Added shared test utilities (tiny_png, send_signed_get, status_code) to common module and refactored three integration test files to replace in-file helper implementations with calls to centralized common module functions, reducing duplication.
Server Logic & Serialization src/adapters/server/auth.rs, src/adapters/wasm.rs	Fixed duplicate query parameter detection in parse_query_params by checking for existing keys before insertion, and added #[serde(skip_serializing)] to exclude large binary bytes from WASM transformation response JSON payloads.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~25 minutes

Possibly related PRs

• Release v0.6.2: fix aarch64 cross-build, release profile, test coverage #56: Adds comprehensive tests for the parse_query_params function that is being fixed in this PR to properly handle duplicate parameters.
• fix: multi-perspective code review batch 1 #132: Introduces separate HEAD request tests that are being consolidated and refactored into a single parameterized test using rstest in this PR.

Poem

🐰 In common burrows, helpers now reside,
Query params checked with proper pride,
With rstest's hop through parameterized tests,
And bytes that skip the JSON's manifest,
Our codebase hops its very best! 🌟

🚥 Pre-merge checks | ✅ 3

✅ Passed checks (3 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately captures the three main changes: test helper consolidation, test parameterization, and the WASM OOM bug fix.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.

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

✨ Finishing Touches

• 📝 Generate docstrings (stacked PR)
• 📝 Generate docstrings (commit on current branch)

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment
• Commit unit tests in branch refactor/code-review-fixes

📝 Coding Plan

• Generate coding plan for human review comments

---

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.}