World 3: Parallel Universes

Rebase basics

You will learn: to move your branch on top of the newest main.

The problem

~/diary $ git log --oneline --graph --all* 01bb13d (main) Make heading teal| * 203a91f (HEAD -> about) Say what I like| * a20da6c Add about page|/  * 270a76e Add style* a8feb63 Add day 1 page* 6d3a9b1 Add README

main moved on while you built about. You want your work on top of the newest main. Without a merge commit.

Watch

git rebase main replays your commits on top of main, one by one. Like moving your work to the end of the line. That’s a .

Try it

You are on about. Rebase it onto main.

Hint

Type git rebase main, then press Enter.

Watch

~/diary $ git log --oneline -n 2203a91f (HEAD -> about) Say what I likea20da6c Add about page~/diary $ git rebase mainSuccessfully rebased and updated refs/heads/about.~/diary $ git log --oneline -n 263ec942 (HEAD -> about) Say what I like0e8659c Add about page

Look at the ids. Same messages, new hashes! A rebase makes new copies of your commits.

Predict

about now sits right on top of main. You merge about into main. What happens?

Try it

Bring about into main. Watch for a fast-forward!

You did it!

You can now rebase a branch onto the newest main.

Go deeper (optional)

A rebase can stop on a conflict too. Fix the file and git add it. Then run git rebase --continue. Changed your mind? git rebase --abort puts everything back. The bottom marker names the commit being replayed.

~/diary $ git rebase mainAuto-merging index.htmlCONFLICT (content): Merge conflict in index.htmlerror: could not apply 0c66136... Add cake dayhint: Resolve all conflicts manually, mark them as resolved withhint: "git add/rm <conflicted_files>", then run "git rebase --continue".hint: You can instead skip this commit: run "git rebase --skip".hint: To abort and get back to the state before "git rebase", run "git rebase --abort".hint: Disable this message with "git config set advice.mergeConflict false"Could not apply 0c66136... # Add cake day~/diary $ git statusinteractive rebase in progress; onto 013a957Last command done (1 command done):   pick 0c66136 # Add cake dayNo commands remaining.You are currently rebasing branch 'cake' on '013a957'.  (fix conflicts and then run "git rebase --continue")  (use "git rebase --skip" to skip this patch)  (use "git rebase --abort" to check out the original branch)Unmerged paths:  (use "git restore --staged <file>..." to unstage)  (use "git add <file>..." to mark resolution)        both modified:   index.htmlno changes added to commit (use "git add" and/or "git commit -a")