minio-rs/.claude/QUICKSTART.md

Quick Start: Test Coverage Commands

Setup (One-time)

Install the coverage tool:

cargo install cargo-llvm-cov

This takes a few minutes but only needs to be done once.

Using the Commands

Check Coverage (Read-only)

Simply type in your Claude Code chat:

/check-coverage

This will:

• Run coverage analysis
• Show you a detailed report
• Tell you exactly what needs testing
• Not make any changes to your code

Generate Tests (Auto-write)

Type in your Claude Code chat:

/test-coverage

This will:

• Run coverage analysis
• Identify gaps
• Automatically create test files
• Write tests following project patterns
• Verify tests compile and run
• Report on coverage improvement

Example Session

You: /check-coverage

Claude:

Coverage Report:
- Overall: 78.5%
- src/madmin/builders/metrics.rs: 45.2% (missing error path tests)
- src/madmin/response/kms_status.rs: 67.8% (missing JSON parse error test)

Recommendations:
1. Add test for metrics builder with invalid parameters
2. Test KMS status response with malformed JSON

You: /test-coverage

Claude:

Analyzing coverage... Installing cargo-llvm-cov...
Running coverage analysis...

Identified 5 uncovered code paths:
1. src/madmin/builders/metrics.rs:85-92 (error handling)
2. src/madmin/response/kms_status.rs:34-38 (JSON parse error)
...

Creating tests:
✓ Created tests/madmin/test_metrics_errors.rs
✓ Created tests/madmin/test_kms_errors.rs
✓ Updated tests/madmin/mod.rs

Running tests...
✓ All 48 tests passing

New coverage: 95.2% (+16.7%)

Remaining gaps:
- src/madmin/types/kms.rs:45 (trivial getter)

Tips

1. Run /check-coverage frequently - It's fast and shows what needs work
2. Use /test-coverage for bulk work - When you've added multiple APIs
3. Review generated tests - They follow patterns but may need refinement
4. Some tests will be ignored - If they need special environment (distributed mode, KMS, etc.)

Troubleshooting

"cargo-llvm-cov not found"

• Run: cargo install cargo-llvm-cov
• Wait for installation to complete

"Tests are failing"

• Check if MinIO server is running
• Verify credentials in environment variables
• Some tests are marked #[ignore] on purpose

"Coverage percentage seems wrong"

• Make sure you're testing the right code (--lib --tests)
• Excluded files (like generated code) won't affect percentage

What Gets Tested

The commands focus on:

• ✅ src/madmin/ - All MinIO Admin API code
• ✅ src/s3/ - All S3 API code
• ✅ Public API methods
• ✅ Error handling paths
• ✅ Builder patterns
• ✅ Response parsing
• ✅ Network error scenarios
• ❌ Test files themselves (not counted in coverage)
• ❌ Generated code (has marker comments)

Tracking Files

After generating tests, the agent updates:

• tests/TEST_COVERAGE.md - Overall statistics and coverage by API category
• tests/API_TEST_MATRIX.md - Detailed test-to-API mappings