# Verification of profile_yaml Fuzz Harness Structure

**Bead ID:** bf-5jzdf  
**Date:** 2026-07-06  
**Task:** Verify profile_yaml fuzz harness file structure

## Summary

Verified that `fuzz/fuzz_targets/profile_yaml.rs` exists and follows the proper fuzzer structure with all required components.

## Acceptance Criteria Verification

| Criterion | Status | Details |
|-----------|--------|---------|
| File exists | ✅ PASS | `fuzz/fuzz_targets/profile_yaml.rs` is present (774 bytes) |
| `#![no_main]` attribute | ✅ PASS | Line 11 contains `#![no_main]` |
| Uses `libfuzzer_sys::fuzz_target!` | ✅ PASS | Line 12 imports `libfuzzer_sys::fuzz_target` |
| Proper UTF-8 handling | ✅ PASS | Lines 16-19: `std::str::from_utf8(data)` with early return on `Err` |
| Calls `load_profile_yaml` | ✅ PASS | Line 22: `pdftract_core::profiles::loader::load_profile_yaml(yaml_content)` |
| No syntax errors | ✅ PASS | File compiles cleanly, follows same pattern as other fuzz targets |

## Comparison with Other Fuzz Targets

Verified against `cmap_parser.rs` to confirm structural consistency:
- Both use `#![no_main]` 
- Both import `libfuzzer_sys::fuzz_target`
- Both use `fuzz_target!(|data: &[u8]| { ... });` macro
- Both have proper documentation comments

## Code Review

The fuzz target correctly implements INV-8 (no panic at public boundary) for the profile YAML loader:
- Converts input bytes to UTF-8 string with early return on invalid UTF-8
- Calls `load_profile_yaml` and discards the result (testing only that it doesn't panic)
- Has clear documentation explaining what invariant it tests

## Conclusion

**Result:** All acceptance criteria PASS. The profile_yaml fuzz harness file structure is correct and ready for use.

**Status:** ✅ COMPLETE - No changes needed, file structure is correct.