ci: diff against PR merge base, not current main tip#416
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The changed-MCPs detection used `git diff $BASE HEAD`, which compares the current tip of main to HEAD — so any path main has touched since the PR forked appeared as "changed" too. Switching to `$BASE...HEAD` uses the merge base, restricting the list to what the PR actually modified. Locally on this branch the result drops from 10 paths (.github, bun.lock, discord, dropbox, github, google-gmail, …) down to the real 3 (.github, hyperdx, scripts). Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
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Summary
The changed-MCPs detection in
checks.ymlusedgit diff "$BASE" HEAD, which compares the current tip ofmainagainstHEAD. So whenevermainhad moved ahead since the PR forked, every path touched onmainshowed up as "changed" too — and theRun type check/Run testssteps ran for MCPs that weren't actually modified by the PR.Switching to
"$BASE"...HEAD(three-dot) uses the merge base, restricting the list to what the PR actually changed.Real example, this branch's parent PR (#403) on the previous CI run:
.github bun.lock deploy.json discord discord-read dropbox github google-gmail package.json vtex.github hyperdx scriptsTest plan
git diff --name-only origin/main...HEADreturns only the paths this PR touches.github(no MCP test/check runs, since no MCP source changed)Summary by cubic
Fix CI changed-MCP detection by diffing against the PR merge base (
git diff "$BASE"...HEAD) instead of the currentmaintip. This prevents unrelated MCP jobs from running whenmainmoves and runs checks only for paths changed by the PR.Written for commit be1fe7f. Summary will update on new commits.