10 Advanced Git workflows that will come in handy
Tags: webdev, git, programming
Published: 2022-11-07 09:13:38

We all know the common Git commands which we use everyday, like `commit`, `push`, `pull` etc.

Here are 10 less known commands which can be very useful. 

1⃣ **Undo a git rebase**

You did a rebase & now you want to undo it. Do git reflog and find the point where you want to go. (Ex: HEAD@{10}) You will find something like the below.
```
git reflog
<sha> HEAD@{9}: rebase: action
<sha> HEAD@{10}: commit: action
```

`HEAD@{9}` is the point where rebase was done. So to revert that, we have to do a hard reset to the previous point.

Use the value to do a hard reset.
```
git reset --hard HEAD@{10}
```
The rebase you did is undone.

2⃣ **Hunt a mysterious bug in your git history**

This command uses a binary search algorithm to find which commit in your project’s history introduced a bug. You use it by first choosing a "bad" commit that is known to contain the bug, and a "good" commit that is known to be clean, before the bug was introduced. Git bisect picks a commit between those two points and asks you whether the selected commit is "good" or "bad". It continues narrowing down the range until it finds the exact commit that introduced the change.

```
git bisect
```

3⃣ **Modify the commit message of a specific commit**

```
git rebase -i head~2
```

The above command display's interactive rebase for the last 2 commits from head. Choose the number based on where your commit lies from head. If it is the 2th commit, choose head~2. You will get something like below

```
pick <sha> <commit message>
pick <sha> <commit message>
```
Change the command to `edit` instead of `pick` from the above, corresponding to the commit you want to modify

```
pick <sha> <commit message>
edit <sha> <commit message>
```
Now go ahead & save and the rebase will stop at the 2nd commit. You can amend the commit to change the commit message. Do git rebase --continue to finish the rebase.

```
git commit --amend
git rebase --continue
```

4⃣ **Amend last commit**

This comes in very handy if you want to change the commit message of the last commit. It can also be used to add new changes to the previous commit, instead of creating a new commit.

```
git commit --amend
```

5⃣ **Recover a dropped stash**

You have dropped a stash, but now you want it back. If you know the hash of the dropped stash you can do the below to retrieve it.

```
git stash apply $stash_hash
```

When you drop a stash, a hash of it is printed on the screen. If you haven't closed your terminal, you can locate it by scrolling to the top of your terminal window. If you can't find it, execute the below command.

```
gitk --all $( git fsck --no-reflog | awk '/dangling commit/ {print $3}' )
```
This will open gitk (git gui). To spot stash commits, look for commit messages that look like this.

```
WIP on somebranch: commithash Some old commit message
```

Once you know the hash of the commit you want, you can apply it as a stash

```
git stash apply $stash_hash
```

6⃣ **Copy a file from one branch to another branch**

If you want to copy an entire file from one branch into another branch, do the below

```
git checkout bugfix README.md
```

`bugfix` is the source branch where the file `README.md` is located. 

Execute the above command from the branch (destination), where you want the file to be copied.

7⃣ **Display the changes in a particular commit or a stash**

```
git show <sha>
git show stash{0}
```

8⃣ **Get the number of commits (Commit count)**

To get the count for a specific revision

```
git rev-list --count <revision>
```

For example `git rev-list --count main` will display the commit count in `main` branch.

To get the count across all branches

```
git rev-list --all --count
```

9⃣ **Revert a specific commit**

Get the <sha> of the commit you want to revert and do this.

```
git revert <sha>
```

🔟 **Rename a local branch**

If you want to rename a branch that is different from the current branch you are in, do this

```
git branch -m <oldname> <newname>
```

If you want to rename the current branch you are in, you can do

```
git branch -m <newname>
```