Git笔记

Git Basics

Getting a Git Repository

git init
git clone git://xxx
git config --system|--global

Recording Changes to the Repository

git status -s
git add
git diff
git difftool --tool-help
git commit -s -a
git rm --cached
git mv file_from file_to

Viewing the Commit History

git log -p -2 --stat
git log --pretty=oneline|short|full|fuller
git log --pretty=format:"%h - %an, %ar : %s"
git log --pretty=format"%h %s" --graph
git log --since=2.weeks|"2008-01-15"|"2 years 1 day 3 minutes ago"
git log --pretty=format:"%h %cd - %s" --author="Patrick Steinhardt" --grep="typo"
git log --pretty=format:"%h %cd - %s" --author="Patrick Steinhardt" --grep="typo" --grep="documentation" --all-match
git log -S code_that_may_be_updated
git log --pretty="%h - %s"--since="2008-01-01" --before="2008-11-01" --no-merges -- src/
git log --decorate  #shows you where the branch pointers are pointing

Undoing Things

# amend your last commit
git commit --amend

# unstaging a staged file
git reset HEAD <file>...

# unmodifying a modified file
git checkout -- <file>...

Working with Remotes

# showing your remotes
git remote -v

# adding remote repositories
git remote add pb https://github.com/paulboone/ticgit

# fetching and pulling from your remotes
git fetch <remote>  # download data but does not merge
git pull <remote>   # download data and merge it

# pushing to your remotes
git push <remote> <branch>

# inspecting a remote
git remote show <remote>

# renaming and removing remotes
git remote rename <old_name> <new_name>
git remote rm <remote>

Tagging

# listing your tags
git tag -l "v0.25*"

# creating annotated tags
git tag -a v1.4 -m "my version 1.4" [commit-checksum]
git show v1.4 # show the tag data along with the commit that was tagged

# create lightweight tags
git tag v1.4.1 [commit-checksum] # dont provide -a, -s, or -m

# sharing tags
git push <remote> <tag-name>
git push <remote> --tags  # push all of your tags

# checking out tags
git checkout <tag-name>  # leads to "detached HEAD state"
git checkout master      # leave "detached HEAD state"

Git Aliases

git config --global alias.co checkout
git config --global alias.br branch
git config --global alias.ci commit
git config --global alias.st status
git config --global alias.unstage 'reset HEAD --'
git config --global alias.last 'log -1 HEAD'

Git Branching

Creating a New Branch

# creating a new branch
git branch testing

# switching branches
git checkout testing

# creating a new branch and switch to it at the same time
git checkout -b iss53

Basic Branching and Merging

# switch to master and merge hotfix into it
git checkout master
git merge hotfix

# delete an unused branch
git branch -d hotfix   # to force delete a branch use -D instead

# merging conflicts
git mergetool --tool-help

Branch management

# show branches
git branch -v

# show the merged branches for the current branch
git branch --merged

# show the unmerged branches for the current branch
git branch --no-merged

# show merged branches for a specified branch
git branch --merged master

Remote Branches

# showing all remote references
git ls-remote <remote>
git remote show <remote>

# sharing your branch
git push <remote> <local_branche_name>[:<remote_branch_name>]

# create local branch based off the remote branch
git checkout -b <local_branch_name> <remote>/<remote_branche_name>
# shortcut if the local branch name is the same as the remote
git checkout [--track] <remote_branch_name> 

# track a different remote branch for the current branch
git branch -u <remote>/<remote_branch_name>

# upstream shothand for merging
git merge @{u}  # a shorthand for 'git merget <remote>/<remote_branch_name>

# showing what tracking branches you have set up
git branch -vv

# getting all the latest commits from all the remote servers
git fetch --all

# deleting remote branches
git push <remote> --delete <remote_branch_name>

Rebasing

git rebase master hotfix
git checkout master
git merge hotfix

Distributed Git

Contributing to a Project

Forked Public Project

# clone and commit your work on a topic branch
git clone <url>
cd project
git checkout -b featureA
... work ...
git commit
... work ...
git commit

# creat a fork of the project e.g named myfork 
# and add it as a new remote of your local repository
git remote add myfork <url>

# push your work
git push -u myfork featureA

# notify the maintainers that you have work you'd like thme to merge
git request-pull origin/master myfork

Public Project over Email

# do work on a topic branch
git checkout -b topicA
... work ...
git commit

# generate the mbox-formatted files that you can email to the list
git format-patch -M origin/master

# send the patches out
cat *.patch | git imap-send  #  imap way
git send-email *.patch       #  SMTP way

Maintaining a project

Applying Patches from E-mail

# contributors use git diff to generate patches
git diff ...
# create a topic branch on which apply patches
git checkout -b sc/ruby_client master
# apply the patch 
git apply /tmp/patch-ruby-client.patch

# check if a patch applies cleanly before acutally applying it
git apply --check xxx.patch

Applying a Patch with am

# contributors use format-patch to generate patches
git format-patch ...

# apply the patch
git am xxx.patch

Checking out Remote Branches

# fetch the commits made by a contributor on a forked remote branch
git remote add jessica git://github.com/jessica/myproject.git
git fetch jessica
git checkout -b rubyclient jessica/ruby-client

# one-time pull from a remote
git pull https//github.com/onetimeguy/project

Determining What Is Introduced

# list the commits that are in your contrib branch but are not in your master branch
git log contrib --not master

# show the common ancestor of two branches
git merge-base contrib master

# show diffs on the contrib branch but not in master
git checkout contrib
git diff $(git merge-base contrib master)

# show only the work your current topic branch has introduced since its common ancestor with master
git diff master...contrib

Integrating Contributed Work

# merge
git merget -3 ...

# rebase
git rebase ...

# cherry-picking a single commit
git cherry-pick e43a6

Preparing a Release

git archive master --prefix='project/' | gzip > `git describe master`.tar.gz
git archive master --prefix='project/' --format=zip > `git describe master`.zip

The Shortlog

git shortlog --no-merges master --not v1.0.1

Git Tools

Revision Selection

Individual Commit

# single revision by short SHA-1
git show <short-sha1>

# single revision by branch references
git show <branch-name>

# show the SHA-1 for a branch
git rev-parse <branch-name>

# reflog
git reflog
git show HEAD@{5}
git show HEAD@{1.month.ago}

# see reflog information in git log
git log -g master

# ancestry references
git show HEAD^     # the parent
git show HEAD^2    # the second parent
git show HEAD~     # the parent
git show HEAD~2    # the parent of the parent

Commit Ranges

# show commits that are not yet pushed to origin/master
git log origin/master..HEAD

# show multiple branches
git log refA refB --not refC
git log refA refB ^refC

# pecifies all the commits that are reachable by either of two references but not by both of them
git log refA...refB --left-right

Interactive Staging

git add -i

Stashing and Cleaning

Stashing your work

# stash your current work
git stash

# list the stashed works
git stash list

# apply the stashed work
git stash apply [--index] [stash@{2}]

# remove a stashed work
git stash drop stash@{2}

# apply the stash and then immediately drop it from your stack
git stash pop

Creative Stashing

# Leave the staged files in the index while stashing
git stash --keep-index

# stash untracked files as well as the tracked ones
git stash -u

# stash interactively
git stash --patch

Creating a Branch from a Stash

git stash branch <branch_name>

Cleaning your Working Directory

# clean the untracked files forcely
git clean -f -d

# see what will be cleaned
git clean -n -d

# remove everything but save it in a stash
git stash --all

# clean the untracked files as well as the ones in .ignore
git clean -f -d -x

Searching

git grep

# search through working directory for a string or regular expression
git grep -n --break --heading <somestring>

# to see how many matches are there
git grep --count <somestring>

# to show the context of a string
git grep -p <somestring>

# search through a give tag for a string
git grep -n <somestring> <tagname>

git log searching

# pickaxe search
git log -S <somestring> --oneline

# line log search
git log -L :funcname:file
git log -L /regexp/,/regexp/:file

Rewriting History

Changing Last Commit

git commit --amend [--no-edit]

Changing Multiple Commit Messages

# prepare to change the last 3 commmits
git rebase -i HEAD~3

# amend the commits
git commit --amend

# continue to rebase
git rebase continue

The Nuclear Option: filter-branch

# remove all the passwords.txt from all the commits
git filter-branch --tree-filter 'rm -f passwords.txt' HEAD

# change e-mail for all the commits
git filter-branch --commit-filter '
      if [ "$GIT_AUTHOR_EMAIL" = "schacon@localhost" ];
      then
          GIT_AUTHOR_NAME="Scott Chacon";
          GIT_AUTHOR_EMAIL="schacon@example.com";
          git commit-tree "$@";
      else
          git commit-tree "$@";
      fi' HEAD

Reset Demystify

Advanced Merging

Aborting a merge

git merge --aborts

Ignoring Whitspace

git merge -Xignore-space-change <branch>

Manual File Re-merging

# show common version, ours version and theirs version
git show :1:<file>
git show :2:<file>
git show :3:<file>

# show SHA-1 of each version in conflicts
git ls-files -u

# merge file
git merge-file -p <current-file> <base-file> <other-file>

# show diffs between working directory and the base, ours or theirs version
git diff --base
git diff --ours
git diff --theirs

Checking Out Conflicts

# Add base versions in the conflict file
git checkout --conflict=diff3 <file>

Merge log

# show the conflict file on each side
git log --oneline --left-right HEAD...MERGE_HEAD
git log --oneline --left-right --merge

revert the commit

git revert -m 1 HEAD
git revert <commit>

Submodules

Add and initialize sub modules

# add a sub module into current project
git submodule add <url>

# clone a project with sub modules
git clone <project_url>
cd <sub_module_dir>
git submodule init
git submodule update

# clone a project with sub modules in one command
git clone --recurse-submodules <project_url>

Working on a Project with Submodules

# fetch and merge the submodule from remote in one command
git submodule update --remote <sub_moudle>