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在将 git 的子树合并到我的项目中之前，我试图确保它对我有用。将子树更改推送到上游存储库时遇到问题。

设置是我有两个存储库sub和main, 并且将存储库main包含sub为subtree.

然后我执行以下操作：

  1. 使用初始提交初始化两个存储库。
  2. 直接更新subrepo（即在 之外main）。
  3. sub从 repo 中更新mainrepo。
  4. sub将（使用）的更改拆分git subtree split为一个单独的分支，然后我将其签出。
  5. 尝试将上游推送到subrepo。自然，此推送会被拒绝，因为它会丢失对sub.
  6. 从subrepo 中提取新的更改。
  7. 尝试将上游推送到subrepo。这一次，它应该工作，但它没有。

我写了一个脚本来封装这个问题。我正在使用subtree启用了模块的 git 版本 1.8.2.1。这是脚本：

#!/bin/bash

echo -n "Wiping old repositories..."
rm -rf main sub sub-home
echo "done"

echo -n "Initializing main and sub repositories..."
mkdir sub-home
( cd sub-home ; git init -q --bare )
git clone sub-home sub > /dev/null 2>&1
( cd sub ; echo subfile > subfile ; git add subfile ;
  git commit -qm "adding root-level file to sub-project" ;
  git push -q origin master )
mkdir main
( cd main ; git init -q ; echo file > file ; git add file ;
  git commit -qm "adding root-level file to main-project" )
echo "done"

echo -n "Adding sub project as a subtree into main project..."
WD=$PWD
( cd main ; git remote add sub-remote file://$WD/sub-home ;
  git subtree add -P sub sub-remote master >/dev/null 2>&1 )
echo "done"

echo -n "Committing to sub-project directly..."
( cd sub ; date > the-date ; git add the-date ;
  git commit -qm "adding the-date to sub-project"
  git push -q origin master )
echo "done"

echo -n "Committing to sub-project from within main project..."
( cd main ; echo 'subfile what?' > sub/subfile ; git add sub/subfile ;
  git commit -qm "changing sub-project from within the main project" )
echo "done"

cd main
git subtree split -q -P sub -b split-branch >/dev/null
git checkout -q split-branch
echo -e "\nPushing from main subtree to sub project, which should fail:"
git push sub-remote master
echo -e "\nBut if we pull first..."
git pull -q --no-edit sub-remote master
echo "...then a push *should* work (but it doesn't):"
git push sub-remote master
cd ..

这是输出：

$ ./test.sh
Wiping old repositories...done
Initializing main and sub repositories...done
Adding sub project as a subtree into main project...done
Committing to sub-project directly...done
Committing to sub-project from within main project...done

Pushing from main subtree to sub project, which should fail:
To file:///tmp/git/sub-home
 ! [rejected]        master -> master (fetch first)
error: failed to push some refs to 'file:///tmp/git/sub-home'
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 merge the remote changes (e.g.,
hint: 'git pull') before pushing again.
hint: See the 'Note about fast-forwards' in 'git push --help' for details.

But if we pull first...
...then a push *should* work (but it doesn't):
To file:///tmp/git/sub-home
 ! [rejected]        master -> master (non-fast-forward)
error: failed to push some refs to 'file:///tmp/git/sub-home'
hint: Updates were rejected because a pushed branch tip is behind its remote
hint: counterpart. Check out this branch and merge the remote changes
hint: (e.g. 'git pull') before pushing again.
hint: See the 'Note about fast-forwards' in 'git push --help' for details.

其他git pull命令（来自 的split-branch分支main）简单地说“已经是最新的”。

真正让我感到困惑的是，据我所知，该git push命令实际上应该给上游 repo 一个快进提交，如下面的git log输出所示：

$ ( cd main ; git log )
commit 357fe9fb42f5d122338940eb4f22d3ca9d276318
Merge: 472904f cb5d1d3
Author: Jeff Terrell <jeff.terrell@acm.org>
Date:   Fri Apr 19 16:03:03 2013 -0400

    Merge branch 'master' of file:///tmp/git/sub-home into split-branch

commit 472904f432c3a0a89acde02691b8281ac5246fd1
Author: Jeff Terrell <jeff.terrell@acm.org>
Date:   Fri Apr 19 16:03:02 2013 -0400

    changing sub-project from within the main project

commit cb5d1d34ce56374f78c98c5b3f3daa314907b62d
Author: Jeff Terrell <jeff.terrell@acm.org>
Date:   Fri Apr 19 16:03:02 2013 -0400

    adding the-date to sub-project

commit 7d1942203d30e0d9e8663517e6d594545bc50640
Author: Jeff Terrell <jeff.terrell@acm.org>
Date:   Fri Apr 19 16:03:02 2013 -0400

    adding root-level file to sub-project
$ (cd sub ; git log )
commit cb5d1d34ce56374f78c98c5b3f3daa314907b62d
Author: Jeff Terrell <jeff.terrell@acm.org>
Date:   Fri Apr 19 16:03:02 2013 -0400

    adding the-date to sub-project

commit 7d1942203d30e0d9e8663517e6d594545bc50640
Author: Jeff Terrell <jeff.terrell@acm.org>
Date:   Fri Apr 19 16:03:02 2013 -0400

    adding root-level file to sub-project

这是我的问题（最后）：

  1. 为什么这个推送被拒绝了？
  2. 我能做些什么呢？（如果使用--force选项是答案，我怎么能确定我没有做破坏性的事情？）
  3. 有没有更好的方法来使用该subtree模块来避免这个问题？（注意：我不愿意使用子模块。）
4

1 回答 1

8

您的问题与git subtree. 您在使用旧的棘手 git ui 时遇到问题。在这种情况下git push。您显然假设它的语法如下git pull。那太天真了——你正在使用 git ;)。

你推送输出告诉你这里出了什么问题：

To file:///tmp/git/sub-home
! [rejected]        master -> master (non-fast-forward)

git pull sub-remote mastersub-remote/master正如您所期望的那样，将 head 提取并合并到您当前签出的分支中。但git push sub-remote master不会将签出分支的头部推入sub-remote/master. 它确实推动了同名的分支。所以在这种情况下master，正如您在上面的输出中看到的那样。

从git help push（语法是git push <repsitory> <refspec>）：

参数的格式<refspec>是可选的加号 +，后跟源 ref <src>，后跟冒号:，然后是目标 ref <dst>。它用于指定要更新远程存储库中<src>的 ref 的对象。<dst>

告诉远程端的<dst>哪个 ref 通过此推送进行更新。此处不能使用任意表达式，必须命名实际的 ref。如果省略，将更新:<dst>相同的 ref 。<src>

所以你要找的命令是git push sub-remote splitbranch:master. 但是你为什么不git subtree push首先使用呢？

于 2013-04-24T08:27:26.263 回答