20取消暂存区部分文件的更改

场景

需要让暂存区的部分文件内容恢复成工作区的文件内容。

实践

 G:\mygitea\GitLearn\learn03   master 
$ git status
On branch master
nothing to commit, working tree clean

 G:\mygitea\GitLearn\learn03   master 
$ cat readme
This is the oldest branch.
This is the older branch.
This is the young branch.
after test, update readme.

 G:\mygitea\GitLearn\learn03   master 
$ cat test.txt
测试

 G:\mygitea\GitLearn\learn03   master 
$ vim test.txt
 测试
+提交到暂存区

 G:\mygitea\GitLearn\learn03   master 
$ vim readme
This is the oldest branch.
This is the older branch.
This is the young branch.
after test, update readme.
+add something.

 G:\mygitea\GitLearn\learn03   master ± 
$ git diff --cached # 由于还未提交到暂存区，因此暂存区与HEAD的文件内容一致

# 此时工作区的文件内容已经变更，与HEAD所指的commit记录的文件内容不一致了。
 G:\mygitea\GitLearn\learn03   master ± 
$ git add .

 G:\mygitea\GitLearn\learn03   master ± 
$ git diff --cached
diff --git a/readme b/readme
index 93d277f..99a1dfa 100644
--- a/readme
+++ b/readme
@@ -2,3 +2,4 @@ This is the oldest branch.
 This is the older branch.
 This is the young branch.
 after test, update readme.
+add something.
diff --git a/test.txt b/test.txt
index f29dee6..f26d326 100644
--- a/test.txt
+++ b/test.txt
@@ -1 +1,2 @@
 测试
+提交到暂存区

此时我们想将test.txt文件恢复回与原来工作目录内容一致：

# 此时将暂存区部分文件恢复成原始的内容，即与HEAD中对应文件内容一致
 G:\mygitea\GitLearn\learn03   master ± 
$ git reset HEAD -- test.txt
Unstaged changes after reset:
M       test.txt

 G:\mygitea\GitLearn\learn03   master ± 
$ git diff --cached # 只有readme文件与HEAD不一致
diff --git a/readme b/readme
index 93d277f..99a1dfa 100644
--- a/readme
+++ b/readme
@@ -2,3 +2,4 @@ This is the oldest branch.
 This is the older branch.
 This is the young branch.
 after test, update readme.
+add something.

# 要注意，此时只是暂存区文件内容恢复成与HEAD一致了，工作区的文件还未恢复
 G:\mygitea\GitLearn\learn03   master ± 
$ cat test.txt
测试
提交到暂存区

 G:\mygitea\GitLearn\learn03   master ± 
$ git checkout test.txt # 暂存区文件覆盖工作区文件
Updated 1 path from the index

 G:\mygitea\GitLearn\learn03   master ± 
$ cat test.txt
测试

至此，我们就将暂存区的部分文件恢复成了原始工作目录的状态了。

总结

git reset HEAD ，是让暂存区恢复为HEAD所指向的节点，使用了该命令后，工作区修改的内容会被保留（保险），如果本地的修改需要丢弃掉，那么可使用—hard。

不过要注意，加了--hard后无法对指定的文件恢复成原始工作区文件内容，只能将暂存区所有的文件恢复成原始工作区文件内容。