TraceId(uint64_t low, uint64_t high) — so the constructor takes (low, high).

In fromTraceparent: TraceId(traceLow, traceHigh) ✓ — this matches the constructor signature.

The test verifies: result.getTraceId() == TraceId(0x9900aabbccddeeff, 0x1122334455667788) which is TraceId(low=0x9900aabbccddeeff, high=0x1122334455667788). And the input traceparent has trace-id 11223344556677889900aabbccddeeff, which has high=1122334455667788 and low=9900aabbccddeeff. This is consistent with toW3C(). Good, the byte ordering is correct.

Now let me do a final assessment. This is a well-implemented, well-tested parser. The code correctly:

• Validates total length
• Validates delimiter positions
• Parses each field with proper hex validation
• Rejects invalid versions, all-zero IDs, and unsampled traces
• Has comprehensive tests covering edge cases

The only thing I'd consider flagging is that the function comment doesn't document the sampled-only behavior. But thinking about it more carefully — this is a minor doc improvement suggestion, not a real code issue. The function returns Maybe<SpanContext> which already signals it can return nothing, and the implementation is clear.

After thorough review, I don't find any actionable issues — no logic bugs, security issues, backward compat violations, memory safety problems, or incorrect API behavior.

LGTM

github run

Codecov Report

❌ Patch coverage is 60.49383% with 32 lines in your changes missing coverage. Please review.
✅ Project coverage is 70.81%. Comparing base (1e952a5) to head (8269c49).
⚠️ Report is 4 commits behind head on main.

@@            Coverage Diff             @@
##             main    #6496      +/-   ##
==========================================
- Coverage   70.82%   70.81%   -0.01%     
==========================================
  Files         435      435              
  Lines      122491   122598     +107     
  Branches    19213    19259      +46     
==========================================
+ Hits        86753    86820      +67     
+ Misses      24373    24372       -1     
- Partials    11365    11406      +41     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.