为什么从非master分支`git pull origin master:master`会导致分支rebase？

Question

我在分支

master

并且做

git log

commit 9937b91089895fac45a39a3bda2935e19eb42554 (HEAD -> master, origin/master, origin/HEAD)
...

git status

打印

On branch master
Your branch is up to date with 'origin/master'.

Untracked files:
  (use "git add <file>..." to include in what will be committed)
        src/orig/

nothing added to commit but untracked files present (use "git add" to track)

和

git branch

打印

  foo
* master

---

打印的 I

git checkout foo

Switched to branch 'foo'
Your branch is up to date with 'origin/foo'.
...

git status

打印

On branch foo
Your branch is up to date with 'origin/foo'.

Untracked files:
  (use "git add <file>..." to include in what will be committed)
        src/orig/

nothing added to commit but untracked files present (use "git add" to track)

和

git branch

打印

* foo
  master

---

我做

git pull origin master:master

，打印

Auto-merging .config/Packages.props
CONFLICT (content): Merge conflict in .config/Packages.props
Auto-merging .corext/corext.config
error: could not apply 2fda5e13a117... Initial commit
hint: Resolve all conflicts manually, mark them as resolved with
hint: "git add/rm <conflicted_files>", then run "git rebase --continue".
hint: You can instead skip this commit: run "git rebase --skip".
hint: To abort and get back to the state before "git rebase", run "git rebase --abort".
hint: Disable this message with "git config advice.mergeConflict false"
Recorded preimage for '.config/Packages.props'
Could not apply 2fda5e13a117... Initial commit

git status

打印

interactive rebase in progress; onto 9937b9108989
Last command done (1 command done):
   pick 2fda5e13a117 Initial commit
No commands remaining.
You are currently rebasing branch 'foo' on '9937b9108989'.
  (fix conflicts and then run "git rebase --continue")
  (use "git rebase --skip" to skip this patch)
  (use "git rebase --abort" to check out the original branch)

Unmerged paths:
  (use "git restore --staged <file>..." to unstage)
  (use "git add <file>..." to mark resolution)
        both modified:   .config/Packages.props

Untracked files:
  (use "git add <file>..." to include in what will be committed)
        src/Services/AZSM/Test/AzSM.SpanningTests/orig/

和

git branch

打印

* (no branch, rebasing foo)
  master

---

然后我执行

git rebase --abort

、

git checkout master

和

git log

打印

commit 9937b91089895fac45a39a3bda2935e19eb42554 (HEAD -> master, origin/master, origin/HEAD)
...

表明

master

没有任何更改被拉入 master（也许没有任何更改）。

---

我认为从

git pull origin master:master

分支运行

foo

相当于

git checkout master
git pull origin master
git checkout foo

但似乎并不是因为

git pull origin master:master

似乎变基了

foo

。

Answer 1

我认为从 foo 分支运行

git pull origin master:master

相当于...

事实并非如此。

git pull

基本上是

git fetch

后跟

git merge

或

git rebase

。

更准确地说，git pull 使用给定的参数运行 git fetch，然后根据配置选项或命令行标志，将调用 git rebase 或 git merge 来协调分歧的分支。

当您运行

git pull origin master:master

时，您基本上是要求 Git 检索远程

master

上的最后更改，并将它们存储到相应的跟踪分支 origin/master 中，而不是合并/变基到您的 上。 master分支。合并/变基部分发生在当前签出的分支上，在您的情况下

foo

。当您执行

git pull

时，它会变基而不是合并，可能是因为您启用了

pull.rebase

 配置，或者 

branch.foo.rebase

 设置为 true。