zoukankan      html  css  js  c++  java
  • 净化Git之rebase变基的使用

    git rebase能够将分叉的分支重新合并,之前写过一篇文章介绍它的原理,下面主要介绍它的两个使用场景:

    场景一:本地与远端同一分支提交历史不一致

    方式一

    多个人在同一个分支上协作时,出现冲突是很正常的,比如现在有一个项目由我和A一同开发。

    我在修复了一个bug以后准备提交

    HowiedeiMac:ganlin howie$ git add models/paper.go
    HowiedeiMac:ganlin howie$ git commit -m 'fix a bug'
    [master 8b76654] fix a bug
     1 file changed, 3 insertions(+), 3 deletions(-)
    

    现在准备推送到远端

    HowiedeiMac:ganlin howie$ git push origin master
    To https://gitee.com/greenhn/ganlin.git
     ! [rejected]        master -> master (fetch first)
    error: failed to push some refs to 'https://gitee.com/greenhn/ganlin.git'
    hint: Updates were rejected because the remote contains work that you do
    hint: not have locally. This is usually caused by another repository pushing
    hint: to the same ref. You may want to first integrate the remote changes
    hint: (e.g., 'git pull ...') before pushing again.
    hint: See the 'Note about fast-forwards' in 'git push --help' for details.
    
    

    push失败了,说明A在我之前已经提交了,我本地master分支的提交历史已经落后远端了,需要先pull一下,与远端同步后才能push

    HowiedeiMac:ganlin howie$ git pull
    remote: Enumerating objects: 14, done.
    remote: Counting objects: 100% (14/14), done.
    remote: Compressing objects: 100% (8/8), done.
    remote: Total 8 (delta 6), reused 0 (delta 0)
    Unpacking objects: 100% (8/8), done.
    From https://gitee.com/greenhn/ganlin
       a1bc60a..b91f711  master     -> origin/master
    Merge made by the 'recursive' strategy.
     controllers/deal_local_data.go | 14 +++++++++++---
     controllers/rtu_interface.go   |  8 ++++----
     models/instrument_type.go      |  3 +++
     models/rtu_interface.go        |  3 +++
     4 files changed, 21 insertions(+), 7 deletions(-)
    
    

    pull成功,现在使用git log看下一提交历史:

    HowiedeiMac:ganlin howie$ git log --oneline --graph
    *   f63ecbf (HEAD -> master) Merge branch 'master' of https://gitee.com/greenhn/ganlin
    |  
    | * b91f711 (origin/master, origin/HEAD) 修正bug,优化内置通道配置
    * | 8b76654 fix a bug
    |/  
    * a1bc60a 完善日报接口
    * 9f73b5e 增加内置通道设置功能
    * a0d464e ...
    
    

    竟然分叉了!由于我本地master的提交历史和远端的master分支的提交历史不一致,所以git为我进行了自动合并,然后生成了一个新的提交历史(f63ecbf Merge branch 'master' of

    对于部分强迫症来说这个不能接受的,不想看到分叉。

    这个时候用git rebase就可以解决

    HowiedeiMac:ganlin howie$ git rebase
    First, rewinding head to replay your work on top of it...
    Applying: fix a bug
    
    

    现在再查看一下提交历史:

    HowiedeiMac:ganlin howie$ git log --oneline --graph
    * 2e2b995 (HEAD -> master) fix a bug
    * b91f711 (origin/master, origin/HEAD) 修正bug,优化内置通道配置
    * a1bc60a 完善日报接口
    * 9f73b5e 增加内置通道设置功能
    * a0d464e ...
    
    

    完美解决,现在再push推送到远端:

    HowiedeiMac:ganlin howie$ git push origin master
    Enumerating objects: 7, done.
    Counting objects: 100% (7/7), done.
    Delta compression using up to 4 threads
    Compressing objects: 100% (4/4), done.
    Writing objects: 100% (4/4), 394 bytes | 394.00 KiB/s, done.
    Total 4 (delta 3), reused 0 (delta 0)
    remote: Powered By Gitee.com
    To https://gitee.com/greenhn/ganlin.git
       b91f711..2e2b995  master -> master
    
    

    再次查看提交历史

    HowiedeiMac:ganlin howie$ git lg --oneline --graph
    * 2e2b995 (HEAD -> master, origin/master, origin/HEAD) fix a bug
    * b91f711 修正bug,优化内置通道配置
    * a1bc60a 完善日报接口
    * 9f73b5e 增加内置通道设置功能
    * a0d464e ...
    

    现在远端master,远端head,本地master全部统一,问题解决。

    方式二

    直接执行:
    git pull --rebase
    效果与上面是一致的,也是最近才发现,推荐使用

    场景二:不同分支之间的合并

    由于老板突发奇想,要求开发一个新的功能。

    先创建一个分支用于开发新功能:

    git checkout -b feature

    HowiedeiMac:hello howie$ git checkout -b feature
    Switched to a new branch 'feature'
    HowiedeiMac:hello howie$ git branch
    * feature
      master
    

    接下来修改newFunc.go,增加新的功能,并且保存提交

    vim newFunc.go

    git add newFunc.go

    git commit -m 'add new func'

    现在查看一下提交

    HowiedeiMac:hello howie$ git log --oneline --graph
    * 4f58ab8 (HEAD -> feature) add new func
    * 94c134b (master) init base
    
    HowiedeiMac:hello howie$ git branch
    * feature
      master
    

    现在新功能开发完毕,需要将它合并的主分支中。

    先尝试通过merge合并:

    首先切换到master分支

    git checkout master

    HowiedeiMac:hello howie$ git checkout master
    Switched to branch 'master'
    Your branch is up to date with 'origin/master'.
    

    直接合并feature分支

    git merge feature

    HowiedeiMac:hello howie$ git merge feature
    Auto-merging newFunc.go
    CONFLICT (content): Merge conflict in newFunc.go
    Automatic merge failed; fix conflicts and then commit the result.
    

    竟然失败了,说明我两个分支之前的版本已经不同步了,需要手动合并冲突,再提交:

    先查看冲突文件:git status

    HowiedeiMac:hello howie$ git status
    On branch master
    Your branch is ahead of 'origin/master' by 7 commits.
      (use "git push" to publish your local commits)
    
    You have unmerged paths.
      (fix conflicts and run "git commit")
      (use "git merge --abort" to abort the merge)
    
    Unmerged paths:
      (use "git add <file>..." to mark resolution)
    
            both modified:   newFunc.go
    

    打开文件,进行修改

    原文件:

    func NewFunc() {
    <<<<<<< HEAD
    =======
        fmt.Println("add new func")
    >>>>>>> feature
    }
    

    修改后:

    func NewFunc() {
        fmt.Println("add new func")
    }
    

    现在通过add添加,然后commit提交

    HowiedeiMac:hello howie$ git add newFunc.go
    
    HowiedeiMac:hello howie$ git commit -m 'merge master and feature'
    [master 562ec58] merge master and feature
    
    

    现在在查看一下分支提交历史:

    HowiedeiMac:hello howie$ git log --oneline --graph
    *   562ec58 (HEAD -> master) merge master and feature
    |  
    | * 4f58ab8 (feature) add new func
    * | 0e80f97 do something
    |/  
    * 94c134b init base
    

    虽然合并成功,但是Master已经保存了合并历史,出现开叉了!对于强迫症患者来说肯定是不能接受的。

    通过rebase合并分支:

    现在将版本退回到合并前,也就是回退一个版本

    git reset --hard head^

    HowiedeiMac:hello howie$ git reset --hard head^
    HEAD is now at 0e80f97 do something
    
    HowiedeiMac:hello howie$ git log --oneline --graph
    * 0e80f97 (HEAD -> master) do something
    * 94c134b init base
    

    退回去了,现在是位于master分支的init base提交这里。

    先切换回feature分支:

    HowiedeiMac:hello howie$ git checkout feature
    Switched to branch 'feature'
    
    

    在feature分支上执行: git rebase master

    这句命令的意识是:以master为基础,将feature分支上的修改增加到master分支上,并生成新的版本。

    HowiedeiMac:hello howie$ git rebase master
    First, rewinding head to replay your work on top of it...
    Applying: add new func
    Using index info to reconstruct a base tree...
    M       newFunc.go
    Falling back to patching base and 3-way merge...
    Auto-merging newFunc.go
    CONFLICT (content): Merge conflict in newFunc.go
    error: Failed to merge in the changes.
    Patch failed at 0001 add new func
    hint: Use 'git am --show-current-patch' to see the failed patch
    
    Resolve all conflicts manually, mark them as resolved with
    "git add/rm <conflicted_files>", then run "git rebase --continue".
    You can instead skip this commit: run "git rebase --skip".
    To abort and get back to the state before "git rebase", run "git rebase --abort".
    
    
    

    失败了,原因很简单,两个分支修改个同一个文件,产生了冲突。所以先需要解决冲突:

    打开冲突的文件,解决冲突

    原文件:

    func NewFunc() {
    <<<<<<< HEAD
    =======
        fmt.Println("add new func")
    >>>>>>> add new func
    }
    

    修改后:

    func NewFunc() {
        fmt.Println("add new func")
    }
    

    现在通过add添加

    HowiedeiMac:hello howie$ git add newFunc.go
    

    现在是重点,之前的rebase其实只是完成了一半,由于出现冲突而终止,现在冲突解决,可以通过git rebase —continue继续完成之前的rebase操作。

    HowiedeiMac:hello howie$ git rebase --continue
    Applying: add new func
    

    rebase完成,再查看一下提交历史:

    HowiedeiMac:hello howie$ git log --oneline --graph
    * b2593e6 (HEAD -> feature) add new func
    * 0e80f97 (master) do something
    * 94c134b init base
    

    提交记录已经是一条完美的直线。现在切换到主分支master,将feather分支上的提交合并过来。

    git checkout master

    git merge feature

    HowiedeiMac:hello howie$ git checkout master
    Switched to branch 'master'
    Your branch is ahead of 'origin/master' by 7 commits.
      (use "git push" to publish your local commits)
    
    
    HowiedeiMac:hello howie$ git merge feature
    Updating 0e80f97..b2593e6
    Fast-forward
     newFunc.go | 1 +
     1 file changed, 1 insertion(+)
    
    

    再次查看一下提交历史:

    HowiedeiMac:hello howie$ git log --oneline --graph
    * b2593e6 (HEAD -> master, feature) add new func
    * 0e80f97 do something
    * 94c134b init base
    
    

    问题解决,master上也是一条直线了。

    其实本质上, 等效于:

    git pull --rebase --autostash origin master

    最后收个尾,删除掉feature分支:

    HowiedeiMac:hello howie$ git branch -d feature
    Deleted branch feature (was b2593e6).
    
     
    总结:
    每次push分支前, 养成及时更新 git base version 的好习惯, 不但 history 清爽, 而且可以避免一个合入的commit 又被提交一次的尴尬.   
    总之, 用它就对了:  git pull --rebase --autostash origin master , 其中master可以换成你要合入的分支
      
    参考 :
    https://www.jianshu.com/p/f7ed3dd0d2d8
  • 相关阅读:
    Android的依赖注入框架:Dagger
    Android第三方开发组件
    Android 应用市场链接上传地址
    Android 开源框架以及开源项目以及连接
    Android 左右侧滑
    Android Textview 跑马灯
    Android XMPP推送
    Android多分辨率设配方案
    Android特效UI
    Android 时间的转换
  • 原文地址:https://www.cnblogs.com/sunsky303/p/12851267.html
Copyright © 2011-2022 走看看