git bisect

Given that HEAD is a bad commit and v2.6.13-rc2 is good, start the bisect process:

git bisect start
git bisect bad
git bisect good v2.6.13-rc2

Next, choose either one of:

git bisect good
git bisect bad

When done:

git bisect reset

Commits That Cannot be Tested

Git’s bisect is one of the reasons, why you should commit working code only. If you have commits that cannot be tested, you may skip them with

git bisect skip

Automation

Create a script that runs your tests and returns an error code that git bisect can use: 0 for success or 1..127 (inclusive) for errors, e.g.

cat <<EOF > /tmp/bisect-run.sh
#!/bin/bash
if pytest; then
    exit 0
else
    exit 1
fi
EOF

chmod +x /tmp/bisect-run.sh

Use it for bisect

git bisect run /tmp/bisect-run.sh

Further Reading

https://git-scm.com/docs/git-bisect

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