To bisect a Git repository to find a commit that introduced a bug, you can use the git bisect command. Here’s a general process on how to use it:
1. Start the Bisect Process: Begin by initializing the bisection process:
git bisect start
2. Mark the Bad Commit: Next, mark the current commit (where the bug is present) as "bad":
git bisect bad
3. Mark a Good Commit: Identify a previous commit where the bug was not present and mark it as "good":
git bisect good <commit-hash>
4. Automate or Manually Check Commits: Git will then automatically check out a commit halfway between the good and bad commits. You need to test this commit to see if the bug is present. After testing, you can mark the commit as bad or good:
git bisect bad # if the bug is present
git bisect good # if the bug is not present
5. Repeat: Repeat the testing and marking process. Git will continue to narrow down the range of commits until it identifies the commit that introduced the bug.
6. Finish Bisecting: Once you've found the bad commit, you can end the bisect session with:
git bisect reset
This process helps you efficiently locate the specific commit that introduced a bug by performing a binary search through the history of your repository.