test: add benchmark for awkward

[APN-Pucky]

See-also: #300

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 97.36%. Comparing base (36c3cce) to head (18c3b33).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

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##             main     #327   +/-   ##
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  Coverage   97.36%   97.36%           
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  Files           2        2           
  Lines         493      493           
  Branches       61       61           
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  Hits          480      480           
  Misses          8        8           
  Partials        5        5           

Flag	Coverage Δ
unittests-3.10	97.36% <ø> (ø)
unittests-3.11	97.36% <ø> (ø)
unittests-3.12	97.36% <ø> (ø)
unittests-3.13	97.36% <ø> (ø)
unittests-3.9	97.07% <ø> (ø)

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[Copilot]

Pull Request Overview

This PR adds a benchmarking infrastructure to measure and compare the performance of awkward array conversion operations across pull requests.

• Adds pytest-benchmark as a test dependency
• Creates benchmark tests for LHEFile.fromfile and to_awkward conversion using multiple test files
• Implements a GitHub Actions workflow to automatically run benchmarks on PRs and post comparison results

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
pyproject.toml	Adds pytest-benchmark dependency to test extras (reordered alphabetically)
benchmarks/test_awkward_bench.py	New benchmark test measuring performance of file loading and awkward array conversion across all test LHE files
.github/workflows/bench.yml	New workflow that runs benchmarks on both main and PR branches, compares results, and posts findings to the PR

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[eduardo-rodrigues]

It looks very good! Looking forward to seeing this in action for nice and useful comparisons.

[eduardo-rodrigues]

One question I meant to ask for my own knowledge - does the benchmark need to go to a benchmarks directory rather than tests? Just curious. Advance thanks.

[APN-Pucky]

Yes. Most distributions don't want to run benchmarks, but only tests. Often that means patching out the benchmark code if it is in tests/ as well (e.g. https://github.com/search?q=repo%3Agentoo%2Fgentoo+pytest-benchmark&type=code).