UPSTREAM PR #2377: feat: add sha256 feature to gix-commitgraph

[loci-dev]

Note

Source pull request: GitoxideLabs/gitoxide#2377

This PR adds the sha256 feature to gix-commitgraph. I opened it as a draft, so we have a space where we can discuss how to best approach testing this new feature.

This PR was triggered by a comment in #2359.

[loci-review]

Overview

Analysis of 27,122 functions across two Gitoxide binaries reveals negligible performance impact between versions. Modified functions: 533 (1.96%), new: 1,009, removed: 1,009, unchanged: 24,571 (90.59%).

Power Consumption:

• target.aarch64-unknown-linux-gnu.release.ein: -0.007% (294,027.58 nJ vs 294,007.38 nJ)
• target.aarch64-unknown-linux-gnu.release.gix: -0.002% (786,468.54 nJ vs 786,452.90 nJ)

Function Analysis

Two functions analyzed show minimal throughput time increases without performance concerns:

rayon_core::StackJob::into_result (ein binary): Throughput time increased 3.85ns (+5.24%), response time stable at 203.9µs (-0.0006%). External dependency function from rayon_core with no source changes. Not in Gitoxide's performance-critical paths.

gix::revision::spec::parse::delegate::Revision::find_ref (ein binary): Throughput time increased 3.49ns (+2.34%), response time stable at 6.92µs (-0.01%). No source code changes detected; variations attributable to compiler optimizations. Used in non-critical revision parsing operations.

Both changes represent normal compiler variance without functional modifications. Performance-critical subsystems (object access, pack operations, parallel processing) remain unaffected.

🔎 Full breakdown: Loci Inspector.
💬 Questions? Tag @loci-dev.