Version: $Revision$
Last-Modified: $Date$
Author: Oleg Broytman <phd@phdru.name>
-Status: Active
+Status: Draft
Type: Informational
Content-Type: text/x-rst
Created: 01-Jun-2015
`Git workflows
<https://www.kernel.org/pub/software/scm/git/docs/gitworkflows.html>`_.
+Advanced documentation
+----------------------
+
`Git Magic
<http://www-cs-students.stanford.edu/~blynn/gitmagic/index.html>`_,
also with a number of translations.
-Advanced documentation
-----------------------
-
`Pro Git <https://git-scm.com/book>`_. The Book about git. Buy it at
Amazon or download in PDF, mobi, or ePub form. Has translations to
many different languages. Download Russian translation from `GArik
Unix users: download and install using your package manager.
Microsoft Windows: download `git-for-windows
-<https://github.com/git-for-windows/git/releases>`_.
+<https://github.com/git-for-windows/git/releases>`_ or `msysGit
+<https://github.com/msysgit/msysgit/releases>`_.
MacOS X: use git installed with `XCode
-<https://developer.apple.com/xcode/downloads/>`_ or download
+<https://developer.apple.com/xcode/downloads/>`_ or download from
+`MacPorts <https://www.macports.org/ports.php?by=name&substr=git>`_ or
`git-osx-installer
-<http://sourceforge.net/projects/git-osx-installer/files/>`_.
+<http://sourceforge.net/projects/git-osx-installer/files/>`_ or
+install git with `Homebrew <http://brew.sh/>`_: ``brew install git``.
+
+`git-cola <https://git-cola.github.io/index.html>`_ is a sleek and
+powerful Git GUI written in Python and GPL licensed. Linux, Windows,
+MacOS X.
+
+`TortoiseGit <https://tortoisegit.org/>`_ is a Windows Shell Interface
+to Git based on TortoiseSVN; open source.
Initial configuration
---------------------
This simple code is often appears in documentation, but it is
-important so let repeat it here. Git marks every commit with author
-and committer names/emails, so configure your real name and preferred
-email::
+important so let repeat it here. Git stores author and committer
+names/emails in every commit, so configure your real name and
+preferred email::
$ git config --global user.name "User Name"
$ git config --global user.email user.name@example.org
supposed that you, the user, works with a local repository named
``python`` that has an upstream remote repo named ``origin``. Your
local repo has two branches ``v1`` and ``v2``. For most examples the
-currently checked out branch is ``v2``. That is, it's assumed you did
-something like that::
+currently checked out branch is ``v2``. That is, it's assumed you have
+done something like that::
+
+ $ git clone -b v2 http://git.python.org/python.git
+ $ cd python
+ $ git branch v1 origin/v1
+
+The last command creates a new local branch v1 and sets
+remotes/origin/v1 as its upstream remote branch.
+
+The same result can achieved with commands::
$ git clone -b v1 http://git.python.org/python.git
$ cd python
- $ git fetch origin v2:v2
- $ git checkout -b v2
+ $ git checkout --track origin/v2
+
+The last command creates a new local branch v2, sets
+remotes/origin/v2 as its upstream remote branch and checks it out into
+the working directory.
Branches and branches
$ git log --decorate
You never do your own development on remote branches. You create a
-local branch that has a remote branch as an upstream and do
-development on that local branch. On push git updates remote branches,
-and on pull git updates remote branches and fast-forwards, merges or
-rebases local branches.
+local branch that has a remote branch as upstream and do development
+on that local branch. On push git updates remote branches, and on pull
+git updates remote branches and fast-forwards, merges or rebases local
+branches.
When you do an initial clone like this::
$ git clone -b v1 http://git.python.org/python.git
git clones remote repository ``http://git.python.org/python.git`` to
-directory ``python``, creates remote branches and checks out branch
-``v1`` into the working directory.
+directory ``python``, creates remote branches, creates a local branch
+``v1``, configure it to track upstream remotes/origin/v1 branch and
+checks out ``v1`` into the working directory.
Updating local and remote branches
----------------------------------
::
$ git fetch REMOTE BRANCH
- $ git merge FETCH_HEAD # FETCH_HEAD is a literal here
+ $ git merge FETCH_HEAD # FETCH_HEAD is a literal here
Certainly, BRANCH in that case should be your current branch. If you
want to merge a different branch into your current branch first update
that non-current branch and then merge::
- $ git fetch origin v1:v1 # Update v1
- $ git pull --rebase origin v2 # Update the current branch v2 using
- # rebase instead of merge
+ $ git fetch origin v1:v1 # Update v1
+ $ git pull --rebase origin v2 # Update the current branch v2 using
+ # rebase instead of merge
+ $ git merge v1
+
+If you have not yet pushed commits on ``v1``, though, the scenario has
+to become a bit more complex. Git refuses to update
+non-fast-forwardable branch, and you don't want to do force-pull
+because that would remove your non-pushed commits and you would need
+to recover. So you want to rebase ``v1`` but you cannot rebase
+non-current branch. Hence, checkout ``v1`` and rebase it before
+merging::
+
+ $ git checkout v1
+ $ git pull --rebase origin v1
+ $ git checkout v2
+ $ git pull --rebase origin v2
$ git merge v1
It is possible to configure git to make it fetch/pull a few branches
You really should push only to bare repositories. For non-bare
repositories git prefers pull-based workflow.
+When you want to deploy code on a remote host and can only use push
+(because your workstation is behind a firewall and you cannot pull
+from it) you do that in two steps using two repositories: you push
+from the workstation to a bare repo on the remote host, ssh to the
+remote host and pull from the bare repo to a non-bare deployment repo.
+
Tags
''''
``git fetch --tags origin``. To fetch some specific tags fetch them
explicitly::
- $ git fetch origin tag NAME1 tag NAME2...
+ $ git fetch origin tag TAG1 tag TAG2...
For example::
Git doesn't automatically pushes tags. That allows you to have private
tags (lightweight tags are also private for a repo, they cannot be
-pushed). To push tag(s) list them explicitly::
+pushed). To push tags list them explicitly::
$ git push origin tag 1.4.2
$ git push origin v1 v2 tag 2.1.7
+Don't move tags with ``git tag -f`` after they have been published.
+
Commit editing and caveats
==========================
been pushed yet. You can even push commits to your own (backup) repo,
edit them later and force-push edited commits to replace what has
already been pushed. Not a problem until commits are in a public
-repository.
+or shared repository.
Undo
https://kernel.org/pub/software/scm/git/docs/howto/revert-a-faulty-merge.html
-Advanced topics
-===============
+Merge or rebase?
+================
-Staging area
-------------
+Internet is full of heated discussions on the topic: "merge or
+rebase?" Most of them are meaningless. When a DVCS is being used in a
+big team with a big and complex project with many branches there is
+simply no way to avoid merges. So the question's diminished to
+"whether to use rebase, and if yes - when to use rebase?" Considering
+that it is very much recommended not to rebase published commits the
+question's diminished even further: "whether to use rebase on
+non-pushed commits?"
-Staging area aka index is a distinguishing feature of git. See
-`WhatIsTheIndex
-<https://git.wiki.kernel.org/index.php/WhatIsTheIndex>`_ and
-`IndexCommandQuickref
-<https://git.wiki.kernel.org/index.php/IndexCommandQuickref>`_ in Git
-Wiki.
+That small question is for the team to decide. The author of the PEP
+recommends to use rebase when pulling, i.e. always do ``git pull
+--rebase`` or even configure automatic setup of rebase for every new
+branch::
+ $ git config branch.autosetuprebase true
-Merge or rebase?
-================
+and configure rebase for existing branches::
+
+ $ git config branch.NAME.rebase true
+
+For example::
+
+ $ git config branch.v2.rebase true
+
+After that ``git pull origin v2`` becomes equivalent to ``git pull
+--rebase origin v2``.
+
+In case when merge is preferred it is recommended to create new
+commits in a separate feature or topic branch while using rebase to
+update the mainline branch. When the topic branch is ready merge it
+into mainline. To avoid a tedious task of resolving conflicts you can
+merge the topic branch to the mainline from time to time and switch
+back to the topic branch to continue working on it. The entire
+workflow would be something like::
+
+ $ git checkout -b issue-42 # create and switch to a new branch
+ ...edit/test/commit...
+ $ git checkout v2
+ $ git pull --rebase origin v2 # update v2 from the upstream
+ $ git merge issue-42
+ $ git branch -d issue-42 # delete the topic branch
+ $ git push origin v2
+
+When the topic branch is deleted only the label is removed, commits
+are stayed in the database, they are now merged into v2::
+
+ o--o--o--o--o--M--< v2 - it is the mainline branch
+ \ /
+ --*--*--* - it is the topic branch, now unnamed
+
+The topic branch is deleted to avoid cluttering branch namespace with
+small topic branches. Information on what issue was fixed or what
+feature was implemented should be in the commit messages.
Null-merges
Git has a builtin strategy for what Python core developers call
"null-merge"::
- $ git merge -s ours v1 # null-merge v1 into v2
+ $ git merge -s ours v1 # null-merge v1 into v2
ReReRe
https://git-scm.com/book/en/Git-Tools-Rerere
+Advanced topics
+===============
+
+Staging area
+------------
+
+Staging area aka index is a distinguishing feature of git. See
+`WhatIsTheIndex
+<https://git.wiki.kernel.org/index.php/WhatIsTheIndex>`_ and
+`IndexCommandQuickref
+<https://git.wiki.kernel.org/index.php/IndexCommandQuickref>`_ in Git
+Wiki.
+
+
Advanced configuration
======================
Tips and tricks
===============
+TODO: sticky options; example: git grep -O.
+
TODO: bash/zsh completion, bash/zsh prompt.
+git on server
+=============
+
+TODO: anonymous access; git over ssh; gitolite; gitweb; cgit; gitlab.
+
+
From Mercurial to git
=====================