Count squash-merge commits into the contributions count

[Moisan]

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• Have you followed our Contributing guidelines?
• Have you checked for other open Pull Requests for the same change?
• Have you explained what your changes do? Performance claims (e.g. "this is faster") must include Hyperfine benchmarks.
• Have you explained why you'd like these changes included, not just what they do?
• For bug fixes, have you given step-by-step brew commands to reproduce the bug?
• Have you written new tests (excluding integration tests)? Here's an example.
• Have you successfully run brew lgtm (style, typechecking and tests) locally?

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• AI was used to generate or assist with generating this PR.

I used codex 5.6 to generate most of the change. I reviewed the code, ran the tests and checked the command output manually for my username.

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The contribution command was ignoring squash-merged PRs and normal merge commits whose head branch is under Homebrew/... rather than a contributor’s fork. (for example Homebrew/homebrew-core#286711 )

A quick check I used: brew contributions --user=moisan --from=2025-12-01 --to=2026-03-01. It was showing no authored PRs previously and 37 with this change.

[Copilot]

Pull request overview

This PR updates brew contributions to include squash-merged (and other non-merge-commit) PRs in contribution counts by supplementing local Git history parsing with a GitHub “merged PRs authored” search.

Changes:

• Always queries GitHub for authored merged PRs in the date range and uses the result to top up per-repository merged_pr_author/merged_pr counts beyond what can be derived from merge commits alone.
• Adds a spec that verifies squash-merged PRs are counted even when a repository has local Git history.
• Updates existing specs to account for the new GitHub merged-PR search.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
Library/Homebrew/dev-cmd/contributions.rb	Adds GitHub merged-PR search and “top-up” logic to count squash-merged PRs alongside Git-derived counts.
Library/Homebrew/test/dev-cmd/contributions_spec.rb	Adds/adjusts specs to validate squash-merge counting and the new GitHub search behavior.

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[MikeMcQuaid]

Thanks! A few comments.

[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

[MikeMcQuaid]

Looks good now, thanks!