Git like Mercurial

Working Locally

Whether you are working by yourself or with others, the workflow for making changes on your local machine stays the same. This guide is primarily aimed at those who are new to version control, but is also useful for seasoned version control users trying to see how gg stacks up to their current tool.

Creating a Repository

To create an empty repository, you use gg init.

gg init foo
cd foo

This will create a new folder foo with a .git directory inside it.

Adding Files

Let’s say you create a file inside your new repository:

nano my-thoughts.txt

gg will not track my-thoughts.txt until you explicitly tell it to, using gg add:

gg add my-thoughts.txt

You can then save your work to the repository using gg commit. This will create a new Git commit.

gg commit -m "Started thinking"

Every commit has a message. A commit message should be a short, human-readable summary of what you did in that commit. A quick internet search for “good commit messages” includes advice on how to write a good commit message and why this is important, especially when collaborating with others.

Modifying Files

Let’s say you add more to my-thoughts.txt. You can get a short summary of the files that have changed by using gg status:

gg status

This would show something like:

M my-thoughts.txt

If you want a more detailed view of your changes, you can use gg diff (short for differences).

gg diff

This would show something like:

diff --git a/my-thoughts.txt b/my-thoughts.txt
--- a/my-thoughts.txt
+++ b/my-thoughts.txt
@@ -1,1 +1,2 @@
 Hello, World!
+I'm learning gg!

When you’re ready to make a new commit, you run gg commit like before.

gg commit -m "Documented my experience in following a gg tutorial"

Long-time Git users will notice that we did not have to “add” the files before committing. This is intentional: gg makes every effort to emulate Mercurial’s index-less model to reduce the number of steps in common workflows. To commit only certain files, just pass them as arguments to gg commit. For more advanced partial commits, use git add and git commit directly.

Removing Files

Sometimes, you will want to remove a file that has been tracked by version control. To do this, you run gg rm followed by gg commit.

gg rm my-thoughts.txt
gg commit -m "Kept my thoughts to myself"

Don’t worry, the file is still in your repository history. Let’s see how to use gg to go back in time.

Examining History

The primary motivation for version control is to be able to inspect previous revisions of files. gg includes several commands to access the repository’s data.

The first command is gg log.

gg log

gg log will show you a list of all the commits you have made up to this point. Each commit is identified by a long hexadecimal string called the hash. You can use the hash to reference the commit in other commands or when talking with other people.

If you want to see the changes made in a single commit, you can pass the -c flag to gg diff with a hash you found from the log.

gg diff -c a199be2

You can also see all the changes made since a particular commit using -r:

gg diff -r a199be2

If you want to check out what the repository looked like at a particular commit, you can use the gg update, also known as checkout.

gg checkout -r a199be2

When you’re done looking, you can go back to your latest work using checkout.

gg checkout -r master

master is the name of the default branch that was created when you ran gg init. You can use the name of a branch instead of a commit hash in any gg command that takes in a commit to indicate the latest commit on that branch.

Finally, if you realize you made a mistake (perhaps you want my-thoughts.txt back), you can use gg revert to bring files back to their state at a given commit, then use gg commit to save your work as normal.

gg revert -r a199be2 my-thoughts.txt
gg commit -m "Brought back my thoughts"

Next Steps

If you are using gg just by yourself, this may be all you need to know. Version control lets you keep track of how your files have changed over time, and lets you bring back files you may have accidentally deleted. However, version control is an important tool for being able to share these changes with others. Once you’ve gotten used to the commands in this guide, take a look at the other workflows to see how to share your work with others. You may also want to look at the command reference.