git rebase -i -autosquash 冲突

Question

git 在使用 --fixup 和 --autosquash 时让我很头疼。 我想举两个例子，一个工作得很好，另一个工作得一团糟。 (git 版本 2.6.2)

工作示例:

第一次提交:

$ git init
$ printf '1\n' > test.file
$ git add test.file
$ git commit -m 'Insert 1 --> first line'  
$ cat test.file
1

第二次提交(BUG):

$ printf 'This is\na BUG\n' >> test.file
$ git commit -am 'Added line 2 and 3 with BUG'
$ cat test.file
1  
This is  
a BUG

第三次提交:

$ sed -i '2i 2' test.file
$ git commit -am 'Insert 2 --> second line'
$ cat test.file
1  
2  
This is  
a BUG

第四次提交(修复):

$ sed -i 's/a BUG/NOT a BUG/' test.file
$ git add test.file
$ git log --oneline
b021696 Insert 2 --> second line  
2e18b8d Added line 2 and 3 with BUG  
d7b60a1 Insert 1 --> first line  
$ git commit --fixup HEAD~
$ cat test.file
1  
2  
This is  
NOT a BUG

rebase :

$ git log --oneline
fe99989 fixup! Added line 2 and 3 with BUG  
b021696 Insert 2 --> second line  
2e18b8d Added line 2 and 3 with BUG  
d7b60a1 Insert 1 --> first line

$ git rebase -i --autosquash HEAD~3

[detached HEAD 6660b0e] Added line 2 and 3 with BUG
Date: Tue Nov 3 13:28:07 2015 +0100
1 file changed, 2 insertions(+)
Successfully rebased and updated refs/heads/master.

---

头痛示例:(唯一的区别是 BUGGY 提交是单行)

第一次提交:

$ git init
$ printf '1\n' > test.file
$ git add test.file
$ git commit -m 'Insert 1 --> first line'  
$ cat test.file
1

第二次提交(BUG):

$ printf 'This is a BUG\n' >> test.file
$ git commit -am 'Added line 2 with BUG'
$ cat test.file
1
This is a BUG

第三次提交:

$ sed -i '2i 2' test.file
$ git commit -am 'Insert 2 --> second line'
$ cat test.file
1  
2  
This is a BUG

第四次提交(修复):

$ sed -i 's/a BUG/NOT a BUG/' test.file
$ git add test.file
$ git log --oneline
2b83fe7 Insert 2 --> second line  
62cdd05 Added line 2 with BUG  
0ee3343 Insert 1 --> first line
$ git commit --fixup HEAD~
$ cat test.file
1  
2  
This is NOT a BUG

rebase :

$ git log --oneline
c3d3db7 fixup! Added line 2 with BUG  
2b83fe7 Insert 2 --> second line  
62cdd05 Added line 2 with BUG  
0ee3343 Insert 1 --> first line
$ git rebase -i --autosquash HEAD~3
error: could not apply c3d3db7... fixup! Added line 2 with BUG

When you have resolved this problem, run "git rebase --continue".
If you prefer to skip this patch, run "git rebase --skip" instead.
To check out the original branch and stop rebasing, run "git rebase --abort".

Could not apply c3d3db78440e48c1bb637f78e0767520db65ea1e... fixup! Added line 2 with BUG

$ git status
interactive rebase in progress; onto 0ee3343
Last commands done (2 commands done):
   pick 62cdd05 Added line 2 with BUG
   fixup c3d3db7 fixup! Added line 2 with BUG
Next command to do (1 remaining command):
   pick 2b83fe7 Insert 2 --> second line
  (use "git rebase --edit-todo" to view and edit)
You are currently rebasing branch 'master' on '0ee3343'.
  (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 reset HEAD <file>..." to unstage)
  (use "git add <file>..." to mark resolution)

        both modified:   test.file

no changes added to commit (use "git add" and/or "git commit -a")  

$ cat test.file
1 
<<<<<<< HEAD
This is a BUG
======= 
2 
This is NOT a BUG
>>>>>>> c3d3db7... fixup! Added line 2 with BUG

---

为什么修复没有完全应用？

为什么 fixup 还包含“2”，它不应该在 fixup 引入的补丁中，而是在前一次提交的补丁中。

Answer 1

我认为问题在于更改的上下文。看看这个提交:

$ git show c3d3db7
diff --git a/test.file b/test.file
index 7a103db..8c8e69a 100644
--- a/test.file
+++ b/test.file
@@ -1,3 +1,3 @@
 1
 2
-This is a BUG
+This is NOT a BUG

并且您想将此补丁应用到包含以下内容的文件:

1
This is a BUG

看到了吗？补丁不适用，因为上下文不匹配。因此出现冲突，您必须手动修复它。

---

当你把 bugger 线一分为二时，补丁是这样的:

diff --git a/test.file b/test.file
--- a/test.file
+++ b/test.file
@@ -1,3 +1,3 @@
 1
 2
 This is
-a BUG
+NOT a BUG

文件是:

1
This is
a BUG

现在，虽然匹配并不完美，但至少上下文的第一行未修改的行匹配，因此 merge 可以继续。