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My Git Command List (1)

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Since I have poor long-term memory in commands, I’ll write down the Git commands that I know.

This list is written for my reference only. Therefore, I won’t include everything. I’m going to write some basic stuff, so that I can review it if I’ve forgotten it. If you want detailed explanation for a command, find the documentation instead. If you’ve encountered a problem using Git, the best teacher is, in general, a search engine.

Initial Setup

Refer to Pro Git section 1.5.

I recommend new Git users to set the configuration variable push.default using git config with the --global option, which make Git save the variables in ~/.gitconfig, so as to avoid the warning shown in Marko’s Stack Overflow question.1 Due to my limited understanding of Git, I couldn’t find a way to suppress the warning after reading the Stack Overflow question. I eventually figured it out after reading a Chinese blog post found in the first footnote.

Initialize repositories

$ git init
$ git init --bare

For the first one, it’s the usual command used for a repository which contains the source code. For the second one, it can be used on a remote server.2

Note: “Running git init on an existing repository is safe.”3

Clone repositories

See Pro Git section 2.1.

From Nowhere man’s answer, I know that one can pass the --bare option to git clone.

$ git clone --bare repo.old repo

In the above command, repo.old is an old repository, and one creates a new bare repository repo from that old non-bare repository.

Get things from remote repositories

There are basic commands: git pull, git fetch and git merge. Roughly speaking, the first one is the “sum” of the following two.

$ git fetch           # fetch from origin/upstream
$ git fetch host      # fetch all branches from remote "host"
$ git fetch host foo  # fetch branch "foo" from remote "host"

Note: In the above codeblock, pull can be substituted by pull.

Before actually merging the branches, we can see their differences first.

Viewing the differences

I only know git diff.

Basic usage

If you’ve written something and have not yet committed your changes, you may issue git diff in the terminal to see the difference between your uncommitted changes and the latest commit. - represents the older committed contents, whereas + represents the newer uncommitted changes.

Compare the tip of the branch with older commits in the same branch

Just appending the first seven digits of the 40-digit SHA-1 hash of the commit to git diff will do.

Comparing branches

I found a page in the official reference. (URL) The <1> form worked well if I compared origin/source and octoress/linklog in ~/octopress. However, I haven’t fully understand this command.

$ git diff origin/source source
fatal: ambiguous argument 'source': both revision and filename
Use '--' to separate paths from revisions, like this:
'git <command> [<revision>...] -- [<file>...]'

(Added on AUG 07TH, 2014)

Now I know how to correct the above Git command. Refer to my newer post Double Hyphens in Git Diff.


Add/remove Files

There are three basic commands:

  • git add
  • git mv
  • git rm

See Charles Bailey’s post for the difference between git add -A and git add ..

$ git add <file>...             # Add <file> to the staging area
$ git add .                     # Add all modified/new files that are tracked
$ git add -A                    # The '-A' flag stands for "all"
$ git mv <file> <new dir/path>  # move the file and record the action in Git
$ git rm <file>                 # delete a file and record the action in Git

I’ve read a simplified Chinese blog post which explained the difference between git rm and rm. (URL)

You may include some untracked files in .gitignore, so that those files will be ignored by Git.

Commit changes

The only command is git commit. There are some basic options that one can make use of.

  • -a (a.k.a. --all): commit changes of all tracked files.
  • --amend: change the commit message of the tip the working branch.
  • -m <msg> (a.k.a. --message): Directly input the commit message.

If the -m flag is used, then an editor window won’t be invoked. In the editor window that contains the commit message, the first line is the header of the commit, while the second line should be left blank. The subsequent lines that don’t begin with # is the content of the commit message.

If you want revert git commit --amend, you may refer to my previous post.

Revert changes

To me, it’s the most important part of this post. I know only two commands for this type of task.

$ git reset HEAD <file>...   # unstage <file>
$ git reset HEAD --soft      # unstage all uncommitted chanages without changing the file(s)
$ git reset HEAD --hard      # revert the files to the latest commit
$ git checkout -- <file>...  # undo all uncommitted changes to <file>

Working with branches

I know that it’s an important feature of Git, but I don’t that very often now, so I just include some simple commands here.

$ git branch                 # list all branches, excluding the remote ones
$ git branch --list          # same as above
$ git branch -a              # list all branches, including the remote ones
$ git branch foo             # create `foo' branch from the current one
$ git checkout foo           # switch to `foo' branch from the current one
$ git checkout -b foo        # the "sum" of the above two commands
$ git branch -d foo          # delete `foo' branch
$ git checkout --orphan foo  # create a new orphan branch named `foo'

When I started using Octopress, I wasn’t familiar with Git. Thus, I messed up the commands that dealt with branches and the network graph of my Git repository of this blog.

Show the history

There’s a GUI way to do so.

$ git show    # Show the diff hunks of recent commits
$ git log     # Show the commits without diff hunks
$ git log -6  # Show the 6 most recent commits
$ git log -p  # Show the commits with diff hunks

Without the -p flag, git log will show the user’s name and email, time, SHA-1 hash, header and content of each commit, but not the diff hunk(s). The key motions for browsing through commits in git log is similar to those in the less utility. If the number of commits isn’t specified, one can browse through the whole commit history by scrolling down to the bottom.

One can use git show to format the output, but I haven’t learnt that.

I am looking forward to writing a second list, but I don’t think I can make it in the next few months.

Some off-topic stuff

gitk

One can invoke gitk, which is a GUI tool for viewing the Git commit for showing history, if he/she doesn’t want to learn the commands in the above section.

fugitive.vim

(EDITED ON FEB 09TH, 2016)

fugitive.vim is a great Vim plugin.

:Gst[atus]      # Show the `git status' on a horizontal split window
:Git <command>  # Equivalent to `:!git <command>'
:Glog           # Show commits of the current file in a quickfix list
:Gllog          # Show commits of the current file in a location list
:Glog --        # Show all commits of the current branch as diff hunks
:Glog -- %      # Show all commits containing the current file as diff hunks
:Glog -- foo    # Show all commits containing the file `foo' as diff hunks

I don’t know the use of :Glog.

Within Gstatus, you can conveniently add/remove files from the staging area.

  • <C-n> and <C-p> jump to the next and previous files respectively.
  • cc is for a Git commit.
  • g? invokes a list of key mappings which can be used in the :Gstatus help window.
  • D is like git diff, but with the layout of vimdiff. By default, one window is on top of another.
  • dv is like D, but one window is on the right of another.

  1. The last sentence of this blog post.

  2. See my post Local Huge File Sharing for details.

  3. Refer to a Stack Overflow question.

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