GitHub多人协作简明教程

本文面向已经了解/熟悉git基本命令但是并不熟悉如何使用GitHub进行多人协作开发项目的同学。

为了简单起见，这里假设只有两个开发人员，HuanianLi 和 DaxiangLi。他们在GitHub上的地址和角色为：

• HuanianLi: https://github.com/huanianli  # Maintainer
• DaxiangLi: https://github.com/daxiangli  # Contributor

HuanianLi将创建一个项目kaiba, 然后请DaxiangLi来帮忙做开发。 为了真实地进行场景演绎，我们将首先创建两个GitHub帐号。

---

1. 在GitHub上创建两个帐号（HuanianLi and DaxiangLi，这里以HuanianLi为例)

1.1 打开GitHub的主页： https://github.com/

1.2 点击右上角的Sign up

1.3 跳转到注册页面后，开始Create your personal account，按照要求输入Username, Email Address, Password, 例如：

1.4 点击页面下方的"Create an account"按钮并按照后续提示完成注册。

---

2. 在Linux桌面上创建两个用户(huanianli and daxiangli)， (这里以huanianli为例)

2.1 创建用户huanianli

root@idorax:~# useradd -d /home/huanianli -m -s /bin/bash -c "Huanian Li" huanianli

2.2 对用户huanianli的git进行设置 （这里直接编辑文件~/.gitconfig）

huanianli@ThinkCentre:~$ vim ~/.gitconfig
huanianli@ThinkCentre:~$ cat -n ~/.gitconfig
         [user]
             email = [e-mail]
             name = Huanian Li
         [core]
             editor = vim
         [push]
             default = matching
huanianli@ThinkCentre:~$
huanianli@ThinkCentre:~$ git config -l
user.email=[e-mail]
user.name=Huanian Li
core.editor=vim
push.default=matching
huanianli@ThinkCentre:~$ 

2.3 在huanianli的HOME目录下创建一个工作空间workspace

huanianli@ThinkCentre:~$ cd ~
huanianli@ThinkCentre:~$ mkdir workspace
huanianli@ThinkCentre:~$ ls
workspace
huanianli@ThinkCentre:~$ 

---

3. (Maintainer) HuanianLi在GitHub上创建一个项目kaiba

3.1 登录HuanianLi的GitHub空间，打开页面Repositories, e.g.

https://github.com/HuanianLi?tab=repositories

点击页面右边的New按钮， 进入创建一个新的代码仓库的页面。

点击"Create repository"完成创建。

3.2 进入HuanianLi的Linux桌面，clone在3.1创建的项目kaiba

huanianli@ThinkCentre:~$ cd workspace
huanianli@ThinkCentre:~/workspace$ git clone https://github.com/HuanianLi/kaiba.git
Cloning into 'kaiba'...
warning: You appear to have cloned an empty repository.
Checking connectivity... done.
huanianli@ThinkCentre:~/workspace$ ls
kaiba
huanianli@ThinkCentre:~/workspace$ cd kaiba
huanianli@ThinkCentre:~/workspace/kaiba$ vi README.md
huanianli@ThinkCentre:~/workspace/kaiba$ cat -n README.md
         kaiba: A sandbox project of Kaiba
huanianli@ThinkCentre:~/workspace/kaiba$
huanianli@ThinkCentre:~/workspace/kaiba$ git add README.md
huanianli@ThinkCentre:~/workspace/kaiba$
huanianli@ThinkCentre:~/workspace/kaiba$ git commit -m "Initialize the project by adding README.md"
[master (root-commit) c0bd2ed] Initialize the project by adding README.md
  file changed,  insertion(+)
 create mode  README.md
huanianli@ThinkCentre:~/workspace/kaiba$
huanianli@ThinkCentre:~/workspace/kaiba$ git log
commit c0bd2ed35e10180209726199af422a63a007355f
Author: Huanian Li <[e-mail]>
Date:   Wed Jul  ::  +

    Initialize the project by adding README.md
huanianli@ThinkCentre:~/workspace/kaiba$
huanianli@ThinkCentre:~/workspace/kaiba$ git branch
* master
huanianli@ThinkCentre:~/workspace/kaiba$
huanianli@ThinkCentre:~/workspace/kaiba$ git push -u origin master
Username for 'https://github.com': HuanianLi
Password for 'https://[e-mail]':
Counting objects: , done.
Writing objects: % (/),  bytes |  bytes/s, done.
Total  (delta ), reused  (delta )
To https://github.com/HuanianLi/kaiba.git
 * [new branch]      master -> master
Branch master set up to track remote branch master from origin.
huanianli@ThinkCentre:~/workspace/kaiba$

在上面的操作中，关键的步骤是：

• clone

git clone https://github.com/HuanianLi/kaiba.git

• push

git push -u origin master

注意： 因为是第一次push, ‘-u’ 是必须的。

3.3 一旦完成git push之后，我们就可以浏览GitHub上的项目了

---

4. (Contributor) DaxiangLi登录他的GitHub,  然后进入(Maintainer) HuanianLi的GitHub空间，fork项目kaiba

4.1 DaxiangLi登录他的GitHub

4.2 进入(Maintainer) HuanianLi的GitHub空间, 点开项目kaiba

注意： 目前的 Fork 为0。

4.3 fork项目kaiba, 直接点Fork按钮

Fork 结束后， DaxiangLi的GitHub里就有了项目kaiba

---

5. （Contributor）DaxiangLi贡献代码给项目kaiba

5.1 DaxiangLi在他的Linux桌面上clone代码

daxiangli@ThinkPad:~/workspace$ git clone https://github.com/DaxiangLi/kaiba.git
Cloning into 'kaiba'...
remote: Counting objects: , done.
remote: Total  (delta ), reused  (delta ), pack-reused
Unpacking objects: % (/), done.
Checking connectivity... done.

两个问题：

• DaxiangLi 能直接clone HuanianLi的GitHub里的代码吗？  A: 能。
• DaxiangLi 能直接clone HuanianLi的GitHub里的代码，然后做修改后push回去吗？ A: 不能。

5.2 DaxiangLi新建一个开发分支

daxiangli@ThinkPad:~/workspace/kaiba$ git checkout -b dev
Switched to a new branch 'dev'

其中， git checkout -b dev 等同于

 git branch   dev
 git checkout dev

5.3 把HuanianLi的项目添加到DaxiangLi的远程仓库

daxiangli@ThinkPad:~/workspace/kaiba$ git remote add upstream https://github.com/HuanianLi/kaiba.git

5.4 将HuanianLi的分支取下来并更新到本地

daxiangli@ThinkPad:~/workspace/kaiba$ git remote update
Fetching origin
Fetching upstream
From https://github.com/HuanianLi/kaiba
 * [new branch]      master     -> upstream/master

daxiangli@ThinkPad:~/workspace/kaiba$ git fetch upstream master
From https://github.com/HuanianLi/kaiba
 * branch            master     -> FETCH_HEAD

5.5 合并HuanianLi的分支到本地(注意：这一步在第一次其实不需要)

daxiangli@ThinkPad:~/workspace/kaiba$ git rebase upstream/master
Current branch dev is up to date.

5.6 DaxiangLi添加一个文件并提交commit

daxiangli@ThinkPad:~/workspace/kaiba$ git add foo.py
daxiangli@ThinkPad:~/workspace/kaiba$ git commit -m "DaxiangLi: Add foo.py"
daxiangli@ThinkPad:~/workspace/kaiba$ git push -u origin dev 

5.7 进入DaxiangLi的GitHub, 提交一个PR

Q: 什么是PR? （参考资料来源点这里）

A: PR是Pull Request的缩写，是开发者使用GitHub进行协作的利器。简单来说，Pull Request是一种机制，让开发者告诉项目成员一个功能已经完成。一旦feature分支开发完毕，开发者使用GitHub账号提交一个Pull Request。它告诉所有参与者，他们需要审查代码，并将代码并入master分支。Pull Request不只是一个通知，还是一个专注于某个提议功能的讨论版面。Pull Request 需要两个不同的分支或是两个不同的仓库, 其工作原理大概是：

1. 开发者在他们的本地仓库中为某个功能创建一个专门的分支；
2. 开发者将分支推送到公共的GitHub仓库；
3. 开发者用GitHub发起一个Pull Request；
4. 其余的团队成员审查代码，讨论并且做出修改；
5. 项目维护者将这个功能并入官方的仓库，然后关闭这个Pull Request。

现在点击Compare & pull request按钮，就创建一个PR,

点页面下方的Create pull request按钮即可。 生成的PR看起来是这样的：

---

6. (Maintainer) HuanianLi 查看PR并Merge

6.1 HuanianLi查看PR

HuanianLi可能在PR中加入comment, 要求DaxiangLi做相应的修改。 这里为简单起见，直接Review通过。

6.2 HuanianLi点Merge pull request

到此为止，DaxiangLi成功地给HuanianLi贡献了一次代码！！ 当然，这次贡献过程异常简单，因为未涉及到冲突解决。接下来将介绍更复杂的情况，这才是重点:-)

6.3 HuanianLi 查看kaiba并删除无用的commit

6.3.1 使用git pull更新本地空间

huanianli@ThinkCentre:~/workspace/kaiba$ git pull
remote: Counting objects: , done.
remote: Compressing objects: % (/), done.
remote: Total  (delta ), reused  (delta ), pack-reused
Unpacking objects: % (/), done.
From https://github.com/HuanianLi/kaiba
   c0bd2ed..b8a0b63  master     -> origin/master
Updating c0bd2ed..b8a0b63
Fast-forward
 foo.py |  ++++++++++++++++
  file changed,  insertions(+)
 create mode  foo.py

注意： 在顶端的commit不是我们想要的，需要把它移除掉。

commit b8a0b63d8b18f8466e79284ed6022340ca5a43a8
Merge: c0bd2ed 640f6f6
Author: Huanian Li <[e-mail]>
Date:   Wed Jul  ::  +

    Merge pull request # from DaxiangLi/dev

    DaxiangLi: Add foo.py

6.3.2 使用git rebase -i移除不需要的commit

huanianli@ThinkCentre:~/workspace/kaiba$ git rebase -i c0bd2ed35e10180209726199af422a63a007355f
Successfully rebased and updated refs/heads/master.

在弹出的交互界面中不做任何修改，直接保存退出即可。

6.3.3 使用git push --force强制更新远端的master分支

huanianli@ThinkCentre:~/workspace/kaiba$ git push --force
Username for 'https://github.com': HuanianLi
Password for 'https://[e-mail]':
Total  (delta ), reused  (delta )
To https://github.com/HuanianLi/kaiba.git
 + b8a0b63...640f6f6 master -> master (forced update)

这下清爽啦！！

---

下面将重点讨论这两种比较复杂的场景：

• 场景一 ： PR Review过程中upstream有更新, 但没有冲突需要解决。例如： DaxiangLi继续修改foo.py, 提交一个PR, 在Review的过程中， HuanianLi增加了一个Makefile并提交了代码。
• 场景二 ： PR Review过程中upstream有更新, 而且需要解决冲突。例如： DaxiangLi继续修改foo.py, 提交一个PR, 在Review的过程中， HuanianLi也修改了foo.py并提交了代码。

这两种场景是常有的事情，因为PR提交后，在review的过程中可能改动多次。那么，在改动的过程中，别的合作伙伴给upstream里贡献了代码并导致commit增加是常有的事情。而且，别的合作伙伴很可能跟你改动了同一个文件，那么你就需要做冲突解决。

---

场景一： PR Review过程中upstream有更新, 但没有冲突需要解决

101 - 在开发之前，DaxiangLi先同步upstream，保证remotes/origin/master与remotes/upstream/master一致

daxiangli@ThinkPad:~/workspace$
daxiangli@ThinkPad:~/workspace$ git clone https://github.com/DaxiangLi/kaiba.git
Cloning into 'kaiba'...
remote: Counting objects: , done.
remote: Compressing objects: % (/), done.
remote: Total  (delta ), reused  (delta ), pack-reused
Unpacking objects: % (/), done.
Checking connectivity... done.
daxiangli@ThinkPad:~/workspace$ cd kaiba
daxiangli@ThinkPad:~/workspace/kaiba$ ls
README.md
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git remote add upstream https://github.com/HuanianLi/kaiba.git
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git remote update
Fetching origin
Fetching upstream
From https://github.com/HuanianLi/kaiba
 * [new branch]      master     -> upstream/master
daxiangli@ThinkPad:~/workspace/kaiba$ ls
README.md
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git fetch upstream master
From https://github.com/HuanianLi/kaiba
 * branch            master     -> FETCH_HEAD
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git rebase upstream/master
First, rewinding head to replay your work on top of it...
Fast-forwarded master to upstream/master.
daxiangli@ThinkPad:~/workspace/kaiba$ ls
foo.py  README.md
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git log
commit 640f6f63f4634915b4e4ed195e9a48d31cabb893
Author: Daxiang Li <bjlhn@.com>
Date:   Wed Jul  ::  +

    DaxiangLi: Add foo.py

commit c0bd2ed35e10180209726199af422a63a007355f
Author: Huanian Li <[e-mail]>
Date:   Wed Jul  ::  +

    Initialize the project by adding README.md
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git branch -a
* master
  remotes/origin/HEAD -> origin/master
  remotes/origin/dev
  remotes/origin/master
  remotes/upstream/master
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git push origin master
Username for 'https://github.com': DaxiangLi
Password for 'https://[e-mail]':
Total  (delta ), reused  (delta )
To https://github.com/DaxiangLi/kaiba.git
   c0bd2ed..640f6f6  master -> master
daxiangli@ThinkPad:~/workspace/kaiba$

102 - DaxiangLi 切换到dev分支

daxiangli@ThinkPad:~/workspace/kaiba$ git branch -a
* master
  remotes/origin/HEAD -> origin/master
  remotes/origin/dev
  remotes/origin/master
  remotes/upstream/master
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git checkout dev
Branch dev set up to track remote branch dev from origin.
Switched to a new branch 'dev'
daxiangli@ThinkPad:~/workspace/kaiba$ git log
commit 640f6f63f4634915b4e4ed195e9a48d31cabb893
Author: Daxiang Li <bjlhn@.com>
Date:   Wed Jul  ::  +

    DaxiangLi: Add foo.py

commit c0bd2ed35e10180209726199af422a63a007355f
Author: Huanian Li <[e-mail]>
Date:   Wed Jul  ::  +

    Initialize the project by adding README.md
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git branch -a
* dev
  master
  remotes/origin/HEAD -> origin/master
  remotes/origin/dev
  remotes/origin/master
  remotes/upstream/master
daxiangli@ThinkPad:~/workspace/kaiba$ 

103 - DaxiangLi修改foo.py并commit，然后push到remotes/origin/dev

daxiangli@ThinkPad:~/workspace/kaiba$ ls
foo.py  README.md
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ vi foo.py
daxiangli@ThinkPad:~/workspace/kaiba$ git diff
diff --git a/foo.py b/foo.py
index 55568dd..4ca134c
--- a/foo.py
+++ b/foo.py
@@ -, +, @@
 import sys

 def main(argc, argv):
+    if argc != :
+        sys.stderr.write("Usage: %s <num>\n" % argv[])
+        return
+
     i =
     while i < int(argv[]):
         print "%02d: Hello World." % i
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git status
On branch dev
Your branch is up-to-date with 'origin/dev'.
Changes not staged for commit:
  (use "git add <file>..." to update what will be committed)
  (use "git checkout -- <file>..." to discard changes in working directory)

    modified:   foo.py

no changes added to commit (use "git add" and/or "git commit -a")
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git commit -a -m "DaxiangLi: add checking to foo.py"
[dev e1bb21e] DaxiangLi: add checking to foo.py
  file changed,  insertions(+)
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git log
commit e1bb21ee432a56fe83d8b3d79048d1623dde0b4d
Author: Daxiang Li <bjlhn@.com>
Date:   Thu Jul  ::  +

    DaxiangLi: add checking to foo.py

commit 640f6f63f4634915b4e4ed195e9a48d31cabb893
Author: Daxiang Li <bjlhn@.com>
Date:   Wed Jul  ::  +

    DaxiangLi: Add foo.py

commit c0bd2ed35e10180209726199af422a63a007355f
Author: Huanian Li <[e-mail]>
Date:   Wed Jul  ::  +

    Initialize the project by adding README.md
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git show
commit e1bb21ee432a56fe83d8b3d79048d1623dde0b4d
Author: Daxiang Li <bjlhn@.com>
Date:   Thu Jul  ::  +

    DaxiangLi: add checking to foo.py

diff --git a/foo.py b/foo.py
index 55568dd..4ca134c
--- a/foo.py
+++ b/foo.py
@@ -, +, @@
 import sys

 def main(argc, argv):
+    if argc != :
+        sys.stderr.write("Usage: %s <num>\n" % argv[])
+        return
+
     i =
     while i < int(argv[]):
         print "%02d: Hello World." % i
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git push origin dev
Username for 'https://github.com': DaxiangLi
Password for 'https://[e-mail]':
Counting objects: , done.
Compressing objects: % (/), done.
Writing objects: % (/),  bytes |  bytes/s, done.
Total  (delta ), reused  (delta )
remote: Resolving deltas: % (/), completed with  local object.
To https://github.com/DaxiangLi/kaiba.git
   640f6f6..e1bb21e  dev -> dev
daxiangli@ThinkPad:~/workspace/kaiba$ 

现在，从DaxiangLi的GitHub空间里可以看到新增加到dev分支的commit e1bb21e。

104 - DaxiangLi为dev分支的commit e1bb21e创建一个PR

105 - HuanianLi开始review DaxiangLi的PR

105.1 在HuanianLi的GitHub空间里看到的PR

105.2 HuanianLi 给PR#2做review, 要求Daxiang Li做修改，于是Daxiang Li看到的PR是

105.3 - DaxiangLi根据HuanianLi的comments做修改

daxiangli@ThinkPad:~/workspace/kaiba$ vi foo.py
daxiangli@ThinkPad:~/workspace/kaiba$ git diff
diff --git a/foo.py b/foo.py
index 4ca134c..84b0787
--- a/foo.py
+++ b/foo.py
@@ -, +, @@ import sys
 def main(argc, argv):
     if argc != :
         sys.stderr.write("Usage: %s <num>\n" % argv[])
-        return
+        return (-)

     i =
     while i < int(argv[]):
         print "%02d: Hello World." % i
         i += 

-    return
+    return ()

 if __name__ == '__main__':
     argv = sys.argv

daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git add foo.py
daxiangli@ThinkPad:~/workspace/kaiba$ git commit -m "DaxiangLi: add checking to foo.py (2)"
[dev d266d6b] DaxiangLi: add checking to foo.py ()
  file changed,  insertions(+),  deletions(-)
daxiangli@ThinkPad:~/workspace/kaiba$ git log
commit d266d6b3f4b6569e82dcd479c020a53f2d5ef556
Author: Daxiang Li <bjlhn@.com>
Date:   Thu Jul  ::  +

    DaxiangLi: add checking to foo.py ()

commit e1bb21ee432a56fe83d8b3d79048d1623dde0b4d
Author: Daxiang Li <bjlhn@.com>
Date:   Thu Jul  ::  +

    DaxiangLi: add checking to foo.py

commit 640f6f63f4634915b4e4ed195e9a48d31cabb893
Author: Daxiang Li <bjlhn@.com>
Date:   Wed Jul  ::  +

    DaxiangLi: Add foo.py

commit c0bd2ed35e10180209726199af422a63a007355f
Author: Huanian Li <[e-mail]>
Date:   Wed Jul  ::  +

    Initialize the project by adding README.md
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git push
Username for 'https://github.com': DaxiangLi
Password for 'https://[e-mail]':
Counting objects: , done.
Compressing objects: % (/), done.
Writing objects: % (/),  bytes |  bytes/s, done.
Total  (delta ), reused  (delta )
remote: Resolving deltas: % (/), completed with  local object.
To https://github.com/DaxiangLi/kaiba.git
   e1bb21e..d266d6b  dev -> dev
daxiangli@ThinkPad:~/workspace/kaiba$ 

105.4 DaxiangLi在PR上做comment, 告诉HuanianLi已经改好了。 （注意： PR上出现了两个commit)

• commit 1: e1bb21e
• commit 2: d266d6b

105.5 HuanianLi 重新检查DaxiangLi的PR

HuanianLi一看DaxiangLi的PR包含了多个commit, 这哪成啊。。。立即给DaxiangLi写comment, 要求合并多个commits为一个commit。

105.6 DaxiangLi着手合并多个commits

daxiangli@ThinkPad:~/workspace/kaiba$ git log
commit d266d6b3f4b6569e82dcd479c020a53f2d5ef556
Author: Daxiang Li <bjlhn@.com>
Date:   Thu Jul  ::  +

    DaxiangLi: add checking to foo.py ()

commit e1bb21ee432a56fe83d8b3d79048d1623dde0b4d
Author: Daxiang Li <bjlhn@.com>
Date:   Thu Jul  ::  +

    DaxiangLi: add checking to foo.py

commit 640f6f63f4634915b4e4ed195e9a48d31cabb893
Author: Daxiang Li <bjlhn@.com>
Date:   Wed Jul  ::  +

    DaxiangLi: Add foo.py

commit c0bd2ed35e10180209726199af422a63a007355f
Author: Huanian Li <[e-mail]>
Date:   Wed Jul  ::  +

    Initialize the project by adding README.md
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git rebase -i 640f6f6
[detached HEAD 7bab5c2] DaxiangLi: add checking to foo.py
 Date: Thu Jul  ::  +
  file changed,  insertions(+),  deletion(-)
Successfully rebased and updated refs/heads/dev.
daxiangli@ThinkPad:~/workspace/kaiba$ git log
commit 7bab5c2d12389b6a5bf5cd602dff684ea336a52e
Author: Daxiang Li <bjlhn@.com>
Date:   Thu Jul  ::  +

    DaxiangLi: add checking to foo.py

commit 640f6f63f4634915b4e4ed195e9a48d31cabb893
Author: Daxiang Li <bjlhn@.com>
Date:   Wed Jul  ::  +

    DaxiangLi: Add foo.py

commit c0bd2ed35e10180209726199af422a63a007355f
Author: Huanian Li <[e-mail]>
Date:   Wed Jul  ::  +

    Initialize the project by adding README.md
daxiangli@ThinkPad:~/workspace/kaiba$ git diff
daxiangli@ThinkPad:~/workspace/kaiba$ git show
commit 7bab5c2d12389b6a5bf5cd602dff684ea336a52e
Author: Daxiang Li <bjlhn@.com>
Date:   Thu Jul  ::  +

    DaxiangLi: add checking to foo.py

diff --git a/foo.py b/foo.py
index 55568dd..84b0787
--- a/foo.py
+++ b/foo.py
@@ -, +, @@
 import sys

 def main(argc, argv):
+    if argc != :
+        sys.stderr.write("Usage: %s <num>\n" % argv[])
+        return (-)
+
     i =
     while i < int(argv[]):
         print "%02d: Hello World." % i
         i += 

-    return
+    return ()

 if __name__ == '__main__':
     argv = sys.argv
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git push --force
Username for 'https://github.com': DaxiangLi
Password for 'https://[e-mail]':
Counting objects: , done.
Compressing objects: % (/), done.
Writing objects: % (/),  bytes |  bytes/s, done.
Total  (delta ), reused  (delta )
remote: Resolving deltas: % (/), completed with  local object.
To https://github.com/DaxiangLi/kaiba.git
 + d266d6b...7bab5c2 dev -> dev (forced update)
daxiangli@ThinkPad:~/workspace/kaiba$ 

注意：

1. 做git push的时候必须使用 'git push --force'
2. 做git rebase -i <commit id>的时候， <commit id>是上一次官方merge的commit id.

关于git rebase -i <commit id>的过程，图解如下：

• 01 - 开始做rebase

• 02 - 进入rebase交互界面，注意阅读各个command的含义

• 03 - 将commit d266d6b应用squash

• 04 - 在vim里按:wq （保存退出）

• 05 - 切换到commit交互界面

• 06 ： 删除L6-9, 然后保存退出vim

105.7 DaxiangLi更改一下commit的comment, 重新push

daxiangli@ThinkPad:~/workspace/kaiba$ git commit --amend
[dev 254347c] DaxiangLi: Add checking to foo.py
 Date: Thu Jul  ::  +
  file changed,  insertions(+),  deletion(-)
daxiangli@ThinkPad:~/workspace/kaiba$ git log
commit 254347cbe57fa043ffcc774e26eabdcd63ea8b30
Author: Daxiang Li <bjlhn@.com>
Date:   Thu Jul  ::  +

    DaxiangLi: Add checking to foo.py

commit 640f6f63f4634915b4e4ed195e9a48d31cabb893
Author: Daxiang Li <bjlhn@.com>
Date:   Wed Jul  ::  +

    DaxiangLi: Add foo.py

commit c0bd2ed35e10180209726199af422a63a007355f
Author: Huanian Li <[e-mail]>
Date:   Wed Jul  ::  +

    Initialize the project by adding README.md
daxiangli@ThinkPad:~/workspace/kaiba$ git push --force
Username for 'https://github.com': DaxiangLi
Password for 'https://[e-mail]':
Counting objects: , done.
Compressing objects: % (/), done.
Writing objects: % (/),  bytes |  bytes/s, done.
Total  (delta ), reused  (delta )
remote: Resolving deltas: % (/), completed with  local object.
To https://github.com/DaxiangLi/kaiba.git
 + db73315...254347c dev -> dev (forced update)

105.8 DaxiangLi重新在PR上加comment, 请HuanianLi再次review (注意: PR上现在只有一个commit了)

105.9 HuanianLi 给kaiba.git里添加一个Makefile, 在检查DaxiangLi的PR最近改动之前

huanianli@ThinkCentre:~/workspace/kaiba$ ls
foo.py  README.md
huanianli@ThinkCentre:~/workspace/kaiba$ git log
commit 640f6f63f4634915b4e4ed195e9a48d31cabb893
Author: Daxiang Li <bjlhn@.com>
Date:   Wed Jul  ::  +

    DaxiangLi: Add foo.py

commit c0bd2ed35e10180209726199af422a63a007355f
Author: Huanian Li <[e-mail]>
Date:   Wed Jul  ::  +

    Initialize the project by adding README.md
huanianli@ThinkCentre:~/workspace/kaiba$
huanianli@ThinkCentre:~/workspace/kaiba$ vi Makefile
huanianli@ThinkCentre:~/workspace/kaiba$ make
cp foo.py foo && chmod +x foo
huanianli@ThinkCentre:~/workspace/kaiba$ ls
foo  foo.py  Makefile  README.md
huanianli@ThinkCentre:~/workspace/kaiba$
huanianli@ThinkCentre:~/workspace/kaiba$ git add Makefile
huanianli@ThinkCentre:~/workspace/kaiba$ git commit -m "HuanianLi: Add Makefile"
[master 3609dff] HuanianLi: Add Makefile
  file changed,  insertions(+)
 create mode  Makefile
huanianli@ThinkCentre:~/workspace/kaiba$ git log
commit 3609dff98de5a17a09484738328a0e9db1784e0d
Author: Huanian Li <[e-mail]>
Date:   Thu Jul  ::  +

    HuanianLi: Add Makefile

commit 640f6f63f4634915b4e4ed195e9a48d31cabb893
Author: Daxiang Li <bjlhn@.com>
Date:   Wed Jul  ::  +

    DaxiangLi: Add foo.py

commit c0bd2ed35e10180209726199af422a63a007355f
Author: Huanian Li <[e-mail]>
Date:   Wed Jul  ::  +

    Initialize the project by adding README.md
huanianli@ThinkCentre:~/workspace/kaiba$ git branch -a
* master
  remotes/origin/master
huanianli@ThinkCentre:~/workspace/kaiba$ git push
Username for 'https://github.com': HuanianLi
Password for 'https://[e-mail]':
Counting objects: , done.
Compressing objects: % (/), done.
Writing objects: % (/),  bytes |  bytes/s, done.
Total  (delta ), reused  (delta )
To https://github.com/HuanianLi/kaiba.git
   640f6f6..3609dff  master -> master
huanianli@ThinkCentre:~/workspace/kaiba$ 

这时候, HuanianLi的master里包含了3个commits, 而DaxiangLi的master里包含了2个commits, dev分支里包含了3个commits。 那么，如果DaxiangLi的dev分支里的top commit (254347c) 被合并到HuanianLi的master分支的时候，这一commit可能成为top commit, 也就是第4个commit，当然也可能成为第3个commit。

 --- HuanianLi's master branch ---
 commit 3609dff HuanianLi: Add Makefile
 commit 640f6f6 DaxiangLi: Add foo.py
 commit c0bd2ed Initialize the project by adding README.md

 --- DaxiangLi's master branch ---
 commit 640f6f6 DaxiangLi: Add foo.py
 commit c0bd2ed Initialize the project by adding README.md

 --- DaxiangLi's dev    branch ---
 commit 254347c DaxiangLi: Add checking to foo.py
 commit 640f6f6 DaxiangLi: Add foo.py
 commit c0bd2ed Initialize the project by adding README.md

 #
 # After commit 7bab5c2 from DaxiangLi's dev    branch
 # is merged into            HuanianLi's master branch
 #
 --- HuanianLi's master branch looks like ---
 commit 254347c DaxiangLi: Add checking to foo.py
 commit 3609dff HuanianLi: Add Makefile
 commit 640f6f6 DaxiangLi: Add foo.py
 commit c0bd2ed Initialize the project by adding README.md

 # OR
 commit 3609dff HuanianLi: Add Makefile
 commit 254347c DaxiangLi: Add checking to foo.py
 commit 640f6f6 DaxiangLi: Add foo.py
 commit c0bd2ed Initialize the project by adding README.md

105.10 HuanianLi再次检查DaxiangLi的PR, 发现只有一个commit了，而且与他的master分支没有冲突，决定merge！！

点击Merge pull request按钮右边的向下箭头，我们可看到有三种Merge方式，这一次，我们将采用Rebase and merge。

105.11 HuanianLi采用Rebase and merge选项处理DaxiangLi的PR

Merge 完毕后，在HuanianLi的GitHub空间可以看到

HuanianLi重新clone一下kaiba.git， 通过git检查Merge:

huanianli@ThinkCentre:~/workspace$ git clone https://github.com/HuanianLi/kaiba.git
Cloning into 'kaiba'...
remote: Counting objects: , done.
remote: Compressing objects: % (/), done.
remote: Total  (delta ), reused  (delta ), pack-reused
Unpacking objects: % (/), done.
Checking connectivity... done.
huanianli@ThinkCentre:~/workspace$ cd kaiba
huanianli@ThinkCentre:~/workspace/kaiba$
huanianli@ThinkCentre:~/workspace/kaiba$ git log
commit 27aca2bcc0fcffb26828cac1eebe517439ef49c9
Author: Daxiang Li <bjlhn@.com>
Date:   Thu Jul  ::  +

    DaxiangLi: Add checking to foo.py

commit 3609dff98de5a17a09484738328a0e9db1784e0d
Author: Huanian Li <[e-mail]>
Date:   Thu Jul  ::  +

    HuanianLi: Add Makefile

commit 640f6f63f4634915b4e4ed195e9a48d31cabb893
Author: Daxiang Li <bjlhn@.com>
Date:   Wed Jul  ::  +

    DaxiangLi: Add foo.py

commit c0bd2ed35e10180209726199af422a63a007355f
Author: Huanian Li <[e-mail]>
Date:   Wed Jul  ::  +

    Initialize the project by adding README.md
huanianli@ThinkCentre:~/workspace/kaiba$ 

106 - DaxiangLi 需要重新sync一下master (这一过程我们在前面介绍过，按照基本套路执行即可)

daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git branch
* dev
  master
daxiangli@ThinkPad:~/workspace/kaiba$ git checkout master
Switched to branch 'master'
Your branch is up-to-date with 'origin/master'.
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git branch
  dev
* master
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git remote -v
origin    https://github.com/DaxiangLi/kaiba.git (fetch)
origin    https://github.com/DaxiangLi/kaiba.git (push)
upstream    https://github.com/HuanianLi/kaiba.git (fetch)
upstream    https://github.com/HuanianLi/kaiba.git (push)
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git remote update
Fetching origin
Fetching upstream
remote: Counting objects: , done.
remote: Compressing objects: % (/), done.
remote: Total  (delta ), reused  (delta ), pack-reused
Unpacking objects: % (/), done.
From https://github.com/HuanianLi/kaiba
   640f6f6..27aca2b  master     -> upstream/master
daxiangli@ThinkPad:~/workspace/kaiba$

daxiangli@ThinkPad:~/workspace/kaiba$ git log
commit 640f6f63f4634915b4e4ed195e9a48d31cabb893
Author: Daxiang Li <bjlhn@.com>
Date:   Wed Jul  ::  +

    DaxiangLi: Add foo.py

commit c0bd2ed35e10180209726199af422a63a007355f
Author: Huanian Li <[e-mail]>
Date:   Wed Jul  ::  +

    Initialize the project by adding README.md
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git fetch upstream master
From https://github.com/HuanianLi/kaiba
 * branch            master     -> FETCH_HEAD
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git rebase upstream/master
First, rewinding head to replay your work on top of it...
Fast-forwarded master to upstream/master.
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git log
commit 27aca2bcc0fcffb26828cac1eebe517439ef49c9
Author: Daxiang Li <bjlhn@.com>
Date:   Thu Jul  ::  +

    DaxiangLi: Add checking to foo.py

commit 3609dff98de5a17a09484738328a0e9db1784e0d
Author: Huanian Li <[e-mail]>
Date:   Thu Jul  ::  +

    HuanianLi: Add Makefile

commit 640f6f63f4634915b4e4ed195e9a48d31cabb893
Author: Daxiang Li <bjlhn@.com>
Date:   Wed Jul  ::  +

    DaxiangLi: Add foo.py

commit c0bd2ed35e10180209726199af422a63a007355f
Author: Huanian Li <[e-mail]>
Date:   Wed Jul  ::  +

    Initialize the project by adding README.md
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git push origin master
Username for 'https://github.com': DaxiangLi
Password for 'https://[e-mail]':
Counting objects: , done.
Compressing objects: % (/), done.
Writing objects: % (/),  bytes |  bytes/s, done.
Total  (delta ), reused  (delta )
remote: Resolving deltas: % (/), completed with  local object.
To https://github.com/DaxiangLi/kaiba.git
   640f6f6..27aca2b  master -> master
daxiangli@ThinkPad:~/workspace/kaiba$

注意： 这里用到的关键命令是：

 $  git checkout master
 $[ git remote add upstream https://github.com/HuanianLi/kaiba.git ]
 $  git remote -v
 $  git remote update
 $  git fetch upstream master
 $  git rebase upstream/master
 $  git push origin master

107 - DaxiangLi将dev分支也sync一下（跟origin master同步即可），以便下一次做开发

daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git branch
  dev
* master
daxiangli@ThinkPad:~/workspace/kaiba$ git checkout dev
Switched to branch 'dev'
Your branch is up-to-date with 'origin/dev'.
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git branch
* dev
  master
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git log
commit 254347cbe57fa043ffcc774e26eabdcd63ea8b30
Author: Daxiang Li <bjlhn@.com>
Date:   Thu Jul  ::  +

    DaxiangLi: Add checking to foo.py

commit 640f6f63f4634915b4e4ed195e9a48d31cabb893
Author: Daxiang Li <bjlhn@.com>
Date:   Wed Jul  ::  +

    DaxiangLi: Add foo.py

commit c0bd2ed35e10180209726199af422a63a007355f
Author: Huanian Li <[e-mail]>
Date:   Wed Jul  ::  +

    Initialize the project by adding README.md
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git fetch origin master
From https://github.com/DaxiangLi/kaiba
 * branch            master     -> FETCH_HEAD
daxiangli@ThinkPad:~/workspace/kaiba$ git rebase origin/master
First, rewinding head to replay your work on top of it...
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git log
commit 27aca2bcc0fcffb26828cac1eebe517439ef49c9
Author: Daxiang Li <bjlhn@.com>
Date:   Thu Jul  ::  +

    DaxiangLi: Add checking to foo.py

commit 3609dff98de5a17a09484738328a0e9db1784e0d
Author: Huanian Li <[e-mail]>
Date:   Thu Jul  ::  +

    HuanianLi: Add Makefile

commit 640f6f63f4634915b4e4ed195e9a48d31cabb893
Author: Daxiang Li <bjlhn@.com>
Date:   Wed Jul  ::  +

    DaxiangLi: Add foo.py

commit c0bd2ed35e10180209726199af422a63a007355f
Author: Huanian Li <[e-mail]>
Date:   Wed Jul  ::  +

    Initialize the project by adding README.md
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git push origin dev
Username for 'https://github.com': DaxiangLi
Password for 'https://[e-mail]':
To https://github.com/DaxiangLi/kaiba.git
 ! [rejected]        dev -> dev (non-fast-forward)
error: failed to push some refs to 'https://github.com/DaxiangLi/kaiba.git'
hint: Updates were rejected because the tip of your current branch is behind
hint: its remote counterpart. Integrate the remote changes (e.g.
hint: 'git pull ...') before pushing again.
hint: See the 'Note about fast-forwards' in 'git push --help' for details.
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git push origin dev --force
Username for 'https://github.com': DaxiangLi
Password for 'https://[e-mail]':
Total  (delta ), reused  (delta )
To https://github.com/DaxiangLi/kaiba.git
 + 254347c...27aca2b dev -> dev (forced update)
daxiangli@ThinkPad:~/workspace/kaiba$ 

注意： 这里用到的关键命令是：

 $ git checkout dev
 $ git fetch origin master
 $ git rebase origin/master
 $ git push origin dev --force

到这里，场景一我们就介绍完毕了, 接下来介绍场景二。

---

场景二： PR Review过程中upstream有更新, 而且需要解决冲突

201 - DaxiangLi第一次更改foo.py

daxiangli@ThinkPad:~$
daxiangli@ThinkPad:~$ rm -rf workspace/kaiba
daxiangli@ThinkPad:~$ cd workspace
daxiangli@ThinkPad:~/workspace$
daxiangli@ThinkPad:~/workspace$ git clone https://github.com/DaxiangLi/kaiba.git
Cloning into 'kaiba'...
remote: Counting objects: , done.
remote: Compressing objects: % (/), done.
remote: Total  (delta ), reused  (delta ), pack-reused
Unpacking objects: % (/), done.
Checking connectivity... done.
daxiangli@ThinkPad:~/workspace$ cd kaiba
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git remote -v
origin    https://github.com/DaxiangLi/kaiba.git (fetch)
origin    https://github.com/DaxiangLi/kaiba.git (push)
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git remote add upstream https://github.com/HuanianLi/kaiba.git
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git remote -v
origin    https://github.com/DaxiangLi/kaiba.git (fetch)
origin    https://github.com/DaxiangLi/kaiba.git (push)
upstream    https://github.com/HuanianLi/kaiba.git (fetch)
upstream    https://github.com/HuanianLi/kaiba.git (push)
daxiangli@ThinkPad:~/workspace/kaiba$

daxiangli@ThinkPad:~/workspace/kaiba$ git branch
* master
daxiangli@ThinkPad:~/workspace/kaiba$ git branch -a
* master
  remotes/origin/HEAD -> origin/master
  remotes/origin/dev
  remotes/origin/master
daxiangli@ThinkPad:~/workspace/kaiba$ git checkout dev
Branch dev set up to track remote branch dev from origin.
Switched to a new branch 'dev'
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git branch
* dev
  master
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ vi foo.py
daxiangli@ThinkPad:~/workspace/kaiba$ git diff foo.py
diff --git a/foo.py b/foo.py
index 84b0787..44635b7
--- a/foo.py
+++ b/foo.py
@@ -, +, @@ def main(argc, argv):
         sys.stderr.write("Usage: %s <num>\n" % argv[])
         return (-)

-    i =
-    while i < int(argv[]):
+    for i in range(int(argv[])):
         print "%02d: Hello World." % i
-        i += 

     return ()

daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git add foo.py
daxiangli@ThinkPad:~/workspace/kaiba$ git commit -m "DaxiangLi: Update foo.py to use for instead of while"
[dev 099cfc7] DaxiangLi: Update foo.py to use for instead of while
  file changed,  insertion(+),  deletions(-)
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git log
commit 099cfc7de963a4cbe8ceb7088a710bdb4815dd9d
Author: Daxiang Li <bjlhn@.com>
Date:   Thu Jul  ::  +

    DaxiangLi: Update foo.py to use for instead of while

commit 27aca2bcc0fcffb26828cac1eebe517439ef49c9
Author: Daxiang Li <bjlhn@.com>
Date:   Thu Jul  ::  +

    DaxiangLi: Add checking to foo.py

commit 3609dff98de5a17a09484738328a0e9db1784e0d
Author: Huanian Li <[e-mail]>
Date:   Thu Jul  ::  +

    HuanianLi: Add Makefile

commit 640f6f63f4634915b4e4ed195e9a48d31cabb893
Author: Daxiang Li <bjlhn@.com>
Date:   Wed Jul  ::  +

    DaxiangLi: Add foo.py

commit c0bd2ed35e10180209726199af422a63a007355f
Author: Huanian Li <[e-mail]>
Date:   Wed Jul  ::  +

    Initialize the project by adding README.md
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git push origin dev
Username for 'https://github.com': DaxiangLi
Password for 'https://[e-mail]':
Counting objects: , done.
Compressing objects: % (/), done.
Writing objects: % (/),  bytes |  bytes/s, done.
Total  (delta ), reused  (delta )
remote: Resolving deltas: % (/), completed with  local objects.
To https://github.com/DaxiangLi/kaiba.git
   27aca2b..099cfc7  dev -> dev
daxiangli@ThinkPad:~/workspace/kaiba$ 

202 - DaxiangLi第二次更改foo.py

提交更新到remotes/origin/dev分支后不满意，于是做第二次修改再提交，这里为了保持只有一个commit, 将会用到

$ git commit -a -m "comments" --amend

全部修改过程如下：

daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git log
commit 099cfc7de963a4cbe8ceb7088a710bdb4815dd9d
Author: Daxiang Li <bjlhn@.com>
Date:   Thu Jul  ::  +

    DaxiangLi: Update foo.py to use for instead of while

commit 27aca2bcc0fcffb26828cac1eebe517439ef49c9
Author: Daxiang Li <bjlhn@.com>
Date:   Thu Jul  ::  +

    DaxiangLi: Add checking to foo.py

commit 3609dff98de5a17a09484738328a0e9db1784e0d
Author: Huanian Li <[e-mail]>
Date:   Thu Jul  ::  +

    HuanianLi: Add Makefile

commit 640f6f63f4634915b4e4ed195e9a48d31cabb893
Author: Daxiang Li <bjlhn@.com>
Date:   Wed Jul  ::  +

    DaxiangLi: Add foo.py

commit c0bd2ed35e10180209726199af422a63a007355f
Author: Huanian Li <[e-mail]>
Date:   Wed Jul  ::  +

    Initialize the project by adding README.md
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git diff
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ vi foo.py
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git add foo.py
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git commit -m "DaxiangLi: Update foo.py to use 'for' instead of 'while'" --amend
[dev 3b9d809] DaxiangLi: Update foo.py to use 'for' instead of 'while'
 Date: Thu Jul  ::  +
  file changed,  insertions(+),  deletions(-)
daxiangli@ThinkPad:~/workspace/kaiba$ git log
commit 3b9d809f249abfd4d5a53d35006d63f341efbacf
Author: Daxiang Li <bjlhn@.com>
Date:   Thu Jul  ::  +

    DaxiangLi: Update foo.py to use 'for' instead of 'while'

commit 27aca2bcc0fcffb26828cac1eebe517439ef49c9
Author: Daxiang Li <bjlhn@.com>
Date:   Thu Jul  ::  +

    DaxiangLi: Add checking to foo.py

commit 3609dff98de5a17a09484738328a0e9db1784e0d
Author: Huanian Li <[e-mail]>
Date:   Thu Jul  ::  +

    HuanianLi: Add Makefile

commit 640f6f63f4634915b4e4ed195e9a48d31cabb893
Author: Daxiang Li <bjlhn@.com>
Date:   Wed Jul  ::  +

    DaxiangLi: Add foo.py

commit c0bd2ed35e10180209726199af422a63a007355f
Author: Huanian Li <[e-mail]>
Date:   Wed Jul  ::  +

    Initialize the project by adding README.md
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git push origin dev --force
Username for 'https://github.com': DaxiangLi
Password for 'https://[e-mail]':
Counting objects: , done.
Compressing objects: % (/), done.
Writing objects: % (/),  bytes |  bytes/s, done.
Total  (delta ), reused  (delta )
remote: Resolving deltas: % (/), completed with  local objects.
To https://github.com/DaxiangLi/kaiba.git
 + 099cfc7...3b9d809 dev -> dev (forced update)
daxiangli@ThinkPad:~/workspace/kaiba$ 

203 - DaxiangLi创建一个PR

204 - HuanianLi更新foo.py并提交到upstream/master分支

huanianli@ThinkCentre:~/workspace/kaiba$
huanianli@ThinkCentre:~/workspace/kaiba$ git log
commit 27aca2bcc0fcffb26828cac1eebe517439ef49c9
Author: Daxiang Li <bjlhn@.com>
Date:   Thu Jul  ::  +

    DaxiangLi: Add checking to foo.py

commit 3609dff98de5a17a09484738328a0e9db1784e0d
Author: Huanian Li <[e-mail]>
Date:   Thu Jul  ::  +

    HuanianLi: Add Makefile

commit 640f6f63f4634915b4e4ed195e9a48d31cabb893
Author: Daxiang Li <bjlhn@.com>
Date:   Wed Jul  ::  +

    DaxiangLi: Add foo.py

commit c0bd2ed35e10180209726199af422a63a007355f
Author: Huanian Li <[e-mail]>
Date:   Wed Jul  ::  +

    Initialize the project by adding README.md
huanianli@ThinkCentre:~/workspace/kaiba$
huanianli@ThinkCentre:~/workspace/kaiba$ vi foo.py
huanianli@ThinkCentre:~/workspace/kaiba$ git diff foo.py
diff --git a/foo.py b/foo.py
index 84b0787..a9aa6fe
--- a/foo.py
+++ b/foo.py
@@ -, +, @@ import sys
 def main(argc, argv):
     if argc != :
         sys.stderr.write("Usage: %s <num>\n" % argv[])
-        return (-)
+        return -

     i =
     while i < int(argv[]):
         print "%02d: Hello World." % i
         i += 

-    return ()
+    return 

 if __name__ == '__main__':
     argv = sys.argv
huanianli@ThinkCentre:~/workspace/kaiba$
huanianli@ThinkCentre:~/workspace/kaiba$
huanianli@ThinkCentre:~/workspace/kaiba$ git commit -a -m "HuanianLi: Update foo.py to use return N instead of return (N)"
[master c5221d8] HuanianLi: Update foo.py to use return N instead of return (N)
  file changed,  insertions(+),  deletions(-)
huanianli@ThinkCentre:~/workspace/kaiba$
huanianli@ThinkCentre:~/workspace/kaiba$ git log
commit c5221d81c91d45cda15e33c3bf0e82874d7fcc97
Author: Huanian Li <[e-mail]>
Date:   Thu Jul  ::  +

    HuanianLi: Update foo.py to use return N instead of return (N)

commit 27aca2bcc0fcffb26828cac1eebe517439ef49c9
Author: Daxiang Li <bjlhn@.com>
Date:   Thu Jul  ::  +

    DaxiangLi: Add checking to foo.py

commit 3609dff98de5a17a09484738328a0e9db1784e0d
Author: Huanian Li <[e-mail]>
Date:   Thu Jul  ::  +

    HuanianLi: Add Makefile

commit 640f6f63f4634915b4e4ed195e9a48d31cabb893
Author: Daxiang Li <bjlhn@.com>
Date:   Wed Jul  ::  +

    DaxiangLi: Add foo.py

commit c0bd2ed35e10180209726199af422a63a007355f
Author: Huanian Li <[e-mail]>
Date:   Wed Jul  ::  +

    Initialize the project by adding README.md
huanianli@ThinkCentre:~/workspace/kaiba$
huanianli@ThinkCentre:~/workspace/kaiba$ git push origin master
Username for 'https://github.com': HuanianLi
Password for 'https://[e-mail]':
Counting objects: , done.
Compressing objects: % (/), done.
Writing objects: % (/),  bytes |  bytes/s, done.
Total  (delta ), reused  (delta )
remote: Resolving deltas: % (/), completed with  local objects.
To https://github.com/HuanianLi/kaiba.git
   27aca2b..c5221d8  master -> master
huanianli@ThinkCentre:~/workspace/kaiba$ 

205 - DaxiangLi再次更新foo.py，故意制造一个冲突

daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git remote update
Fetching origin
Fetching upstream
remote: Counting objects: , done.
remote: Compressing objects: % (/), done.
remote: Total  (delta ), reused  (delta ), pack-reused
Unpacking objects: % (/), done.
From https://github.com/HuanianLi/kaiba
 * [new branch]      master     -> upstream/master
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git branch -a
* dev
  master
  remotes/origin/HEAD -> origin/master
  remotes/origin/dev
  remotes/origin/master
remotes/upstream/master

daxiangli@ThinkPad:~/workspace/kaiba$ vi foo.py
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git commit -a --amend
[dev 924729d] DaxiangLi: Update foo.py to use 'for' instead of 'while'
 Date: Thu Jul  ::  +
  file changed,  insertions(+),  deletions(-)

daxiangli@ThinkPad:~/workspace/kaiba$ git diff remotes/origin/master..
diff --git a/foo.py b/foo.py
index 84b0787..b1070a5
--- a/foo.py
+++ b/foo.py
@@ -, +, @@ import sys
 def main(argc, argv):
     if argc != :
         sys.stderr.write("Usage: %s <num>\n" % argv[])
-        return (-)
+        return (-)

-    i =
-    while i < int(argv[]):
-        print "%02d: Hello World." % i
-        i +=
+    for i in range(int(argv[])):
+        print "%02d: Hello World." % (i + )

     return ()

daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git diff remotes/upstream/master..
diff --git a/foo.py b/foo.py
index a9aa6fe..b1070a5
--- a/foo.py
+++ b/foo.py
@@ -, +, @@ import sys
 def main(argc, argv):
     if argc != :
         sys.stderr.write("Usage: %s <num>\n" % argv[])
-        return -
+        return (-)

-    i =
-    while i < int(argv[]):
-        print "%02d: Hello World." % i
-        i +=
+    for i in range(int(argv[])):
+        print "%02d: Hello World." % (i + )

-    return
+    return ()

 if __name__ == '__main__':
     argv = sys.argv
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git push --force
Username for 'https://github.com': DaxiangLi
Password for 'https://[e-mail]':
Counting objects: , done.
Compressing objects: % (/), done.
Writing objects: % (/),  bytes |  bytes/s, done.
Total  (delta ), reused  (delta )
remote: Resolving deltas: % (/), completed with  local objects.
To https://github.com/DaxiangLi/kaiba.git
 + 671404d...924729d dev -> dev (forced update)
daxiangli@ThinkPad:~/workspace/kaiba$ 

• 制造的冲突是故意将return (-1)改成return (-11)

• 接下来我们发现，PR上就会显示有冲突了！！

• 冲突的细节在于foo.py的第8行

好吧，接下来DaxiangLi就需要去解决冲突了！

206 - DaxiangLi解决冲突 (P.S. 解决冲突不是很容易，请仔细看)

206.1 创建一个临时分支dev-scratch （为了演示得更清晰，这里故意删除旧的空间，重新clone一遍，然后从头开始）

daxiangli@ThinkPad:~/workspace/kaiba$ git checkout -b dev-scratch dev
Switched to a new branch 'dev-scratch'

206.2 给临时分支dev-scratch添加upstream的repo

daxiangli@ThinkPad:~/workspace/kaiba$ git remote add upstream https://github.com/HuanianLi/kaiba.git

206.3 让临时分支dev-scratch与upstream/master同步

daxiangli@ThinkPad:~/workspace/kaiba$ git remote update
Fetching origin
Fetching upstream
remote: Counting objects: , done.
remote: Compressing objects: % (/), done.
remote: Total  (delta ), reused  (delta ), pack-reused
Unpacking objects: % (/), done.
From https://github.com/HuanianLi/kaiba
 * [new branch]      master     -> upstream/master

daxiangli@ThinkPad:~/workspace/kaiba$ git fetch upstream master
From https://github.com/HuanianLi/kaiba
 * branch            master     -> FETCH_HEAD

daxiangli@ThinkPad:~/workspace/kaiba$ git merge upstream/master
Auto-merging foo.py
CONFLICT (content): Merge conflict in foo.py
Automatic merge failed; fix conflicts and then commit the result.

206.4 在临时分支dev-scratch里合并冲突

daxiangli@ThinkPad:~/workspace/kaiba$ git add foo.py
daxiangli@ThinkPad:~/workspace/kaiba$ git commit -m "DaxiangLi: Merge confilict in foo.py"
[dev-scratch c9af088] DaxiangLi: Merge confilict in foo.py

206.5 将本地的临时分支dev-scratch与本地开发分支dev做比较

daxiangli@ThinkPad:~/workspace/kaiba$ git diff dev..dev-scratch

206.6 切换到本地开发分支dev

daxiangli@ThinkPad:~/workspace/kaiba$ git checkout dev
Switched to branch 'dev'
Your branch is up-to-date with 'origin/dev'.

206.7 将临时分支dev-scratch合并到开发分支dev

daxiangli@ThinkPad:~/workspace/kaiba$ git merge --squash dev-scratch
Updating 924729d..c9af088
Fast-forward
Squash commit -- not updating HEAD
 foo.py |  ++--
  file changed,  insertions(+),  deletions(-)

daxiangli@ThinkPad:~/workspace/kaiba$ git commit -a --amend
[dev 5055a77] DaxiangLi: Update foo.py to use 'for' instead of 'while'
 Date: Thu Jul  ::  +
  file changed,  insertions(+),  deletions(-)
daxiangli@ThinkPad:~/workspace/kaiba$
daxiangli@ThinkPad:~/workspace/kaiba$ git diff dev..dev-scratch
daxiangli@ThinkPad:~/workspace/kaiba$ 

206.8 把本地的开发dev强制推送到远端的开发dev

daxiangli@ThinkPad:~/workspace/kaiba$ git push origin dev --force
Username for 'https://github.com': DaxiangLi
Password for 'https://[e-mail]':
Counting objects: , done.
Compressing objects: % (/), done.
Writing objects: % (/),  bytes |  bytes/s, done.
Total  (delta ), reused  (delta )
remote: Resolving deltas: % (/), completed with  local objects.
To https://github.com/DaxiangLi/kaiba.git
 + 924729d...5055a77 dev -> dev (forced update)

206.9 删除本地的临时分支dev-scratch

daxiangli@ThinkPad:~/workspace/kaiba$ git branch dev-scratch -D
Deleted branch dev-scratch (was c9af088).

OKAY, 冲突解决完成！ 重新刷新PR, 发现冲突已经不存在啦。。。

207 - HuanianLi再次检查PR，发现没有冲突，将代码Rebase and merge

208 - DaxiangLi重新sync远端的master分支

• 使用下面一组命令即可 (其中， [*]为关键命令)

 [ ] $ git branch
 [*] $ git checkout master
 [ ] $ git branch
 [ ] $ git log
 [*] $ git remote add upstream https://github.com/HuanianLi/kaiba.git
 [ ] $ git remote -v
 [ ] $ git remote update
 [*] $ git fetch  upstream master
 [*] $ git rebase upstream/master
 [ ] $ git log
 [ ] $ git diff remotes/origin/master..
 [*] $ git push origin master

209 - DaxiangLi重新sync远端的dev分支 (前面其实已经介绍过)

• 使用下面的命令即可 (其中， [*]为关键命令)

 [*] $ git clone https://github.com/DaxiangLi/kaiba.git
 [*] $ git checkout dev
 [ ] $ git remote -v
 [*] $ git remote add upstream https://github.com/HuanianLi/kaiba.git
 [ ] $ git remote -v
 [ ] $ git log
 [ ] $ git remote update
 [*] $ git fetch  upstream master
 [*] $ git rebase upstream/master
 [ ] $ git log --graph
 [*] $ git push origin dev --force

说明： git remote update可以不做，直接使用git fetch upstream master也okay.

---

总结：

1. 从upstream fork出代码空间后，总是创建一个dev分支并保存到远端比较好，这样master分支用来与upstream保持同步，dev分支用来做开发
2. 提交PR的时候请在dev分支中总是保存一个用来被合作伙伴review的commit，如不小心提交了多个commit, 需要进行合并，合并的方法是使用git rebase -i
3. 保持PR中只有一个commit的秘诀是使用git commit -a --amend，然后使用git push origin dev --force
4. 养成总是让origin/master与upstream同步的好习惯
5. 不用总是让origin/dev与upstream保持同步，如果PR中显示有冲突就解决冲突，没有就不用管，即使origin/dev与upstream不同步 （P.S. git没有recommit功能，所以你无法总是把你的commit放置到top位置）
6. 当一个PR被合并后，不妨也让origin/dev分支与upstream同步，同步的秘诀还是git push origin dev --force
7. 可以认为origin/dev分支是一个沙箱，可以用来随便玩, 玩坏了大不了删除远端的origin/dev分支再重新创建一个；但是请认真对待origin/master
8. 尽可能地使用git rebase upstream/master, 不使用git merge upstream/master, 在做同步的时候
9. 解决冲突请创建一个本地临时分支dev-scratch, 然后将临时分支合并到本地开发分支dev，合并的秘诀是使用 git merge --squash dev-scratch
10. 不需要的临时分支dev-scratch用git branch dev-scratch -D删除，养成不留垃圾分支的好习惯
11. 不小心关掉一个PR可以Re-open, 但是尽量不要在review的过程中删除被review的commit，那样会导致PR被自动关闭

---

参考资料：

• Git教程
• A successful Git branching model
• 怎样在github上协同开发
• 使用git和github进行协同开发流程
• GitHub实现多人协同提交代码并且权限分组管理