10 Tips to Push Your Git Skills to the Next Level

http://www.sitepoint.com/10-tips-git-next-level/

Recently we published a couple of tutorials to get you familiar with Git basics and using
Git in a team environment. The commands that we discussed were about enough to help a developer survive in the Git world. In this post, we will try to explore how to manage your time effectively and make full use of the features that Git provides.

Note: Some commands in this article include part of the command in square brackets (e.g.

git
add -p [file_name]

). In those examples, you would insert the necessary number, identifier, etc. without the square brackets.

1. Git Auto Completion

If you run Git commands through the command line, it’s a tiresome task to type in the commands manually every single time. To help with this, you can enable auto completion of Git commands within a few minutes.

To get the script, run the following in a Unix system:

Next, add the following lines to your

~/.bash_profile

file:

Although I have mentioned this earlier, I can not stress it enough: If you want to use the features of Git fully, you should definitely shift to the command line interface!

2. Ignoring Files in Git

Are you tired of compiled files (like

.pyc

) appearing in your Git repository? Or are you so
fed up that you have added them to Git? Look no further, there is a way through which you can tell Git to ignore certain files and directories altogether. Simply create a file with the name

.gitignore

and
list the files and directories that you don’t want Git to track. You can make exceptions using the exclamation mark(!).

3. Who Messed With My Code?

It’s the natural instinct of human beings to blame others when something goes wrong. If your production server is broke, it’s very easy to find out the culprit — just do a

git
blame

. This command shows you the author of every line in a file, the commit that saw the last change in that line, and the timestamp of the commit.



And in the screenshot below, you can see how this command would look on a bigger repository:

4. Review History of the Repository

We had a look at the use of

git log

in a previous tutorial, however, there are three options
that you should know about.

--oneline

– Compresses the information shown
beside each commit to a reduced commit hash and the commit message, all shown in a single line.

--graph

– This option draws a text-based
graphical representation of the history on the left hand side of the output. It’s of no use if you are viewing the history for a single branch.

--all

– Shows the history of all branches.

Here’s what a combination of the options looks like:

5. Never Lose Track of a Commit

Let’s say you committed something you didn’t want to and ended up doing a hard reset to come back to your previous state. Later, you realize you lost some other information in the process and want to get it back, or at least view it. This is where

git
reflog

can help.

A simple

git log

shows you the latest commit, its parent, its parent’s parent, and so on. However,

git
reflog

is a list of commits that the head was pointed to. Remember that it’s local to your system; it’s not a part of your repository and not included in pushes or merges.

If I run

git log

, I get the commits that are a part of my repository:



However, a

git reflog

shows a commit (

b1b0ee9

–

HEAD@{4}

)
that was lost when I did a hard reset:

6. Staging Parts of a Changed File for a Commit

It is generally a good practice to make feature-based commits, that is, each commit must represent a feature or a bug fix. Consider what would happen if you fixed two bugs, or added multiple features without committing the changes. In such a situation situation,
you could put the changes in a single commit. But there is a better way: Stage the files individually and commit them separately.

Let’s say you’ve made multiple changes to a single file and want them to appear in separate commits. In that case, we add files by prefixing

-p

to
our add commands.

Let’s try to demonstrate the same. I have added three new lines to

file_name

and I want only
the first and third lines to appear in my commit. Let’s see what a

git diff

shows us.



And let’s see what happes when we prefix a

-p

to our

add

command.



It seems that Git assumed that all the changes were a part of the same idea, thereby grouping it into a single hunk. You have the following options:

Enter y to stage that hunk
Enter n to not stage that hunk
Enter e to manually edit the hunk
Enter d to exit or go to the next file.
Enter s to split the hunk.

In our case, we definitely want to split it into smaller parts to selectively add some and ignore the rest.



As you can see, we have added the first and third lines and ignored the second. You can then view the status of the repository and make a commit.

7. Squash Multiple Commits

When you submit your code for review and create a pull request (which happens often in open source projects), you might be asked to make a change to your code before it’s accepted. You make the change, only to be asked to change it yet again in the next review.
Before you know it, you have a few extra commits. Ideally, you could squash them into one using the

rebase

command.

If you want to squash the last two commits, the command that you run is the following.

On running this command, you are taken to an interactive interface listing the commits and asking you which ones to squash. Ideally, you

pick

the
latest commit and

squash

the old ones.



You are then asked to provide a commit message to the new commit. This process essentially re-writes your commit history.

8. Stash Uncommitted Changes

Let’s say you are working on a certain bug or a feature, and you are suddenly asked to demonstrate your work. Your current work is not complete enough to be committed, and you can’t give a demonstration at this stage (without reverting the changes). In such
a situation,

git stash

comes to the rescue. Stash essentially takes all your changes and stores
them for further use. To stash your changes, you simply run the following-

To check the list of stashes, you can run the following:



If you want to un-stash and recover the uncommitted changes, you apply the stash:

In the last screenshot, you can see that each stash has an indentifier, a unique number (although we have only one stash in this case). In case you want to apply only selective stashes, you add the specific identifier to the

apply

command:

9. Check for Lost Commits

Although

reflog

is one way of checking for lost commits, it’s not feasible in large repositories.
That is when the

fsck

(file system check) command comes into play.



Here you can see a lost commit. You can check the changes in the commit by running

git show [commit_hash]

or
recover it by running

git merge [commit_hash]

.

git fsck

has an advantage over

reflog

.
Let’s say you deleted a remote branch and then cloned the repository. With

fsck

you can search
for and recover the deleted remote branch.

10. Cherry Pick

I have saved the most elegant Git command for the last. The

cherry-pick

command is by far my
favorite Git command, because of its literal meaning as well as its utility!

In the simplest of terms,

cherry-pick

is picking a single commit from a different branch and
merging it with your current one. If you are working in a parallel fashion on two or more branches, you might notice a bug that is present in all branches. If you solve it in one, you can cherry pick the commit into
the other branches, without messing with other files or commits.

Let’s consider a scenario where we can apply this. I have two branches and I want to

cherry-pick

the
commit

b20fd14: Cleaned junk

into another one.



I switch to the branch into which I want to

cherry-pick

the commit, and run the following:



Although we had a clean

cherry-pick

this time, you should know that this command can often lead
to conflicts, so use it with care.

Conclusion

With this, we come to the end of our list of tips that I think can help you take your Git skills to a new level. Git is the best out there and it can accomplish anything you can imagine. Therefore, always try to challenge yourself with Git. Chances are, you
will end up learning something new!