[Git][多人协作][上]详细讲解

0.命令补充

• git branch只能查看本地分支，如果要查看远程分支需要加上-r选项，即git branch -r
  • 如果本地是的分支情况是落后与远端的，需要先git pull一下才能看到远端分支

    $ git branch -r
      origin/dev
      origin/main
      
    $ git pull
    From github.com:DieSnowK/Git-Learn
     * [new branch]      test       -> origin/test
    Already up to date.
    
    $ git branch -r
      origin/dev
      origin/main
      origin/test
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• 查看本地和远程仓库的所有分支：git branch -a
• 查看本地分支和远端分支的联系情况：git branch -vv
• 查看远程仓库详细信息：git remote show origin
• 本地如何获取到远端已有的新分支？
  • 在本地git pull之后，本地是没有dev分支的，需要在本地新建dev分支，并与远端的origin/dev分支建立联系
  • 方法一：本地新建分支时直接建立联系
    • git checkout -b branch_name origin/branch_name
  • 方法二：本地已经建立分支了，后续再单独建立联系
    • git branch --set-upstream-to=origin/branch_name branch_name
• 如果要在远端仓库上新建分支，该如何做？
  • 方法一：直接在远端仓库新建分支(推荐)
    • 这样能保证新建的分支绝对是以main为基准，且是最新的
  • 方法二：本地创建分支，再push
    • 此时会有些许麻烦 --> 本地的main是最新的吗？
    • 为了解决上述问题，通常需要在新建本地分支前，在本地main分支git pull一下
    • 然后创建本地分支，并直接推送至远端：git push origin branch_name

1.同一分支下多人协作

• 情景设置：
  • 目标：master分支下，SnowK.txt文件新增代码Die和SnowK
  • 实现：开发者A新增Die，开发者B新增SnowK
  • 条件：在一个分支下协作完成
• 开发者A：由于先提交，没有遇到问题

  $ cat SnowK.txt
  Die
  
  $ git add .
  
  $ git commit -m "A push sth"
  [dev de4ac94] A push sth
   1 file changed, 1 insertion(+)
   
  $ git push
  Enumerating objects: 5, done.
  Counting objects: 100% (5/5), done.
  Delta compression using up to 20 threads
  Compressing objects: 100% (2/2), done.
  Writing objects: 100% (3/3), 281 bytes | 281.00 KiB/s, done.
  Total 3 (delta 0), reused 0 (delta 0), pack-reused 0
  To github.com:DieSnowK/Git-Learn.git
     6981c9d..de4ac94  dev -> dev
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• 开发者B：提交时遇到问题，被远端仓库拒绝提交
  • 原因：开发者A最新提交的代码和开发者B此时推送的提交有冲突

  $ cat SnowK.txt
  SnowK
  
  $ git add .
  
  $ git commit -m "B push sth"
  [dev 074d5ec] B push sth
   1 file changed, 1 insertion(+)
   
  $ git push
  To github.com:DieSnowK/Git-Learn.git
   ! [rejected]        dev -> dev (fetch first)
  error: failed to push some refs to 'github.com:DieSnowK/Git-Learn.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.
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• 如何解决上述问题？
  • 开发者B先git pull将远端代码从origin/dev拉取下来
  • 然后，在本地进行合并，并解决冲突，再重新提交并推送

    $ git pull
    remote: Enumerating objects: 5, done.
    remote: Counting objects: 100% (5/5), done.
    remote: Compressing objects: 100% (2/2), done.
    remote: Total 3 (delta 0), reused 3 (delta 0), pack-reused 0
    Unpacking objects: 100% (3/3), 261 bytes | 16.00 KiB/s, done.
    From github.com:DieSnowK/Git-Learn
       6981c9d..de4ac94  dev        -> origin/dev
    Auto-merging SnowK.txt
    CONFLICT (content): Merge conflict in SnowK.txt
    Automatic merge failed; fix conflicts and then commit the result.
    
    # 解决冲突ing
    
    $ cat SnowK.txt
    Die
    SnowK
    
    $ git add .
    
    $ git commit -m "solve the conflict, merge from origin/dev"
    [dev 10cd204] solve the conflict, merge from origin/dev
    
    $ git push
    Enumerating objects: 10, done.
    Counting objects: 100% (10/10), done.
    Delta compression using up to 20 threads
    Compressing objects: 100% (4/4), done.
    Writing objects: 100% (6/6), 636 bytes | 636.00 KiB/s, done.
    Total 6 (delta 0), reused 0 (delta 0), pack-reused 0
    To github.com:DieSnowK/Git-Learn.git
       de4ac94..10cd204  dev -> dev
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• 此时，远端仓库的dev分支，已经是最新版本，但是要如何将该dev分支合并至main分支呢？
  • 方法一：在远端仓库提出Pull Request(PR)，交由审查员审核后合并
  • 方法二：以下为一个习惯良好的流程，避免出现问题
    • 切换至本地main分支，git pull拉取下最新的main分支

      $ git checkout main
      Switched to branch 'main'
      Your branch is up to date with 'origin/main'.
      
      $ git pull
      Already up to date.
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    • 本地切换至dev分支，合并main分支
      • 目的：如果有冲突，可以在dev分支解决，以避免对main分支造成影响

      $ git checkout dev
      Switched to branch 'dev'
      Your branch is up to date with 'origin/dev'.
      
      $ git merge main
      Already up to date.
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    • 切换至本地main分支，合并dev分支，并将main分支推送至远端

      $ git checkout main
      Switched to branch 'main'
      Your branch is up to date with 'origin/main'.
      
      $ git merge dev
      Updating 6241400..10cd204
      Fast-forward
       SnowK.txt | 3 +++
       1 file changed, 3 insertions(+)
       create mode 100644 SnowK.txt
       
      $ cat SnowK.txt
      Die
      SnowK
      
      $ git status
      On branch main
      Your branch is ahead of 'origin/main' by 5 commits.
        (use "git push" to publish your local commits)
      
      nothing to commit, working tree clean
      
      $ git push origin main
      Total 0 (delta 0), reused 0 (delta 0), pack-reused 0
      To github.com:DieSnowK/Git-Learn.git
         6241400..10cd204  main -> main
         
      $ git status
      On branch main
      Your branch is up to date with 'origin/main'.
      
      nothing to commit, working tree clean
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    • dev分支已经完成它的任务，可以删除远端和本地的dev分支了
• 总结：在同⼀分⽀下进⾏多⼈协作的⼯作模式
  • ⾸先，可以试图⽤git push origin branch-name推送⾃⼰的修改
  • 如果推送失败，则因为远程分⽀⽐本地更新，需要先⽤git pull试图合并
  • 如果合并有冲突，则解决冲突，并在本地提交
  • 没有冲突或者解决掉冲突后，再⽤git push origin branch-name推送就能成功
  • 功能开发完毕，将分⽀merge进main，最后删除分⽀