Find the commit that introduced a bug

Bash

Binary search across history. Mark a known good and a known bad commit and git narrows it down for you.

git bisect start
git bisect bad                 # current HEAD is broken
git bisect good v1.4.0         # this tag was fine
# test, then: git bisect good | git bisect bad
git bisect reset

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Git git bisect debugging chris

More in Git

Search the whole history for a string Git Finds every commit whose diff added or removed a piece of text, including in files long since deleted. Recover a branch you deleted Git The reflog remembers where HEAD has been for about ninety days, so a deleted branch is almost never really gone. Show what a merge will do before doing it Git Lists the commits and the files a merge would bring in, so a surprise is less likely. Amend a commit without changing its message Git Adds forgotten files to the previous commit and leaves the message exactly as it was. Stop tracking a file without deleting it Git For the config file that should never have been committed. Add it to .gitignore afterwards. List branches merged into main Git Finds the branches that are safe to delete, and the ones that are not. Undo the last commit but keep the changes Git Moves HEAD back one commit and leaves everything staged, which is what you usually want after committing too early.

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