In summary, when looking to incorporate changes from one Git branch into another: Use merge in cases where you want a set of commits to be clearly grouped together in history. Use rebase when you want to keep a linear commit history. DON'T use rebase on a public/shared branch.
The git rebase command is used to merge the history of two branches on a repository. It is often used to integrate changes from one branch onto another branch. You should only use the git rebase command locally; it should not be used on a public repository.
Rebase will do the rest of the work, deleting only that commit, and replaying all of the others back into the log.
git rebase --onto allows you to, in a non-interactive way, change the base of a commit, or rebase it. If you think about the commits as each having a base, or parent commit, you can see how you might be able to change the base of any commit to be another commit.
Git rebase and merge both integrate changes from one branch into another. Where they differ is how it's done. Git rebase moves a feature branch into a master. Git merge adds a new commit, preserving the history.
Git Squash Commits
Squashing is a way to rewrite your commit history; this action helps to clean up and simplify your commit history before sharing your work with team members. Squashing a commit in Git means that you are taking the changes from one commit and adding them to the Parent Commit.- Step 1: Keep going git rebase --continue.
- Step 2: fix CONFLICTS then git add .
- Back to step 1, now if it says no changes .. then run git rebase --skip and go back to step 1.
- If you just want to quit rebase run git rebase --abort.
- Once all changes are done run git commit -m "rebase complete" and you are done.
- Find a previous branching point of the branch to be rebased (moved) - call it old parent. In the example above that's A.
- Find commit on top of which you want to move the branch to - call it new parent.
- You need to be on your branch (the one you move):
- Apply your rebase: git rebase --onto <new parent> <old parent>
Here's the workflow:
- git commit-edit <commit-hash> This will drop you at the commit you want to edit.
- Fix and stage the commit as you wish it had been in the first place.
- Redo the commit with --amend , eg: git commit --amend.
- Complete the rebase: git rebase --continue.
Changing older or multiple commits. To modify older or multiple commits, you can use git rebase to combine a sequence of commits into a new base commit. In standard mode, git rebase allows you to literally rewrite history — automatically applying commits in your current working branch to the passed branch head.
The Rebase OptionBut, instead of using a merge commit, rebasing re-writes the project history by creating brand new commits for each commit in the original branch. This makes it easier to navigate your project with commands like git log , git bisect , and gitk .
From merge to rebase
- Create a new “feature” branch called `my-new-feature` from a base branch, such as `master` or `develop`
- Do some work and commit the changes to the feature branch.
- Push the feature branch to the centralized shared repo.
- Open a new Pull Request for `my-new-feature`
Git merging combines sequences of commits into one unified history of commits. There are two main ways Git will merge: Fast Forward and Three way. Git can automatically merge commits unless there are changes that conflict in both commit sequences.
Rebase a branch on top of another branch
- From the main menu select Git | Rebase:
- From the list, select the target branch onto which you want to rebase the current branch:
Generally this is done by merging, i.e. the local changes are merged into the remote changes. So git pull is similar to git fetch & git merge . Rebasing is an alternative to merging. Instead of creating a new commit that combines the two branches, it moves the commits of one of the branches on top of the other.
Git Rebase: A Git Workflow explained — Part 2
- Prerequisites :
- Step 1: Fork and clone the desired repo.
- Step 2: Set upstream.
- Step 3: Create a branch from the dev branch of the upstream.
- Step 4: Rebase your branch with the dev branch (Sync your fork)
- Step 5: Push your branch to the origin.
A fast-forward is what Git does when you merge or rebase against a branch that is simply ahead the one you have checked-out. Given the following branch setup: You've got both branches referencing the same commit. It simply updates the master branch to reference the same commit that feature does.
Usually, you want to clear your Git cache because you added new entries in your gitignore files and you want them to be taken into account. The easiest way to clear your Git cache is to use the “git rm” command with the “–cached” option. You can choose to remove one file or to remove an entire working directory.
Git Rebase Steps
- Switch to the branch/PR with your changes. Locally set your Git repo to the branch that has the changes you want merged in the target branch.
- Execute the Git rebase command.
- Fix all and any conflicts.
- Force push the new history.
Resolving merge conflicts after a Git rebase
- You can run git rebase --abort to completely undo the rebase. Git will return you to your branch's state as it was before git rebase was called.
- You can run git rebase --skip to completely skip the commit.
- You can fix the conflict.
The git add command adds new or changed files in your working directory to the Git staging area. git add is an important command - without it, no git commit would ever do anything. git add allows you to shape history without changing how you work.
