大話git中的撤銷操作

下麵以現實場景作為情境。

基礎知識，理解git中的幾個區域

本地代碼已經add，未commit

修改本地工作目錄中的readme.md,添加文字"第一次修改"

然後查看下狀態

➜  experimentation git:(master) ✗ git status
On branch master
Your branch is up-to-date with 'origin/master'.
Changes not staged for commit:
  (use "git add <file>..." to update what will be committed)
  (use "git checkout -- <file>..." to discard changes in working directory)

        modified:   README.md

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

進行Add操作,並查看狀態

➜  experimentation git:(master) ✗ git add README.md
➜  experimentation git:(master) ✗ git status
On branch master
Your branch is up-to-date with 'origin/master'.
Changes to be committed:
  (use "git reset HEAD <file>..." to unstage)

        modified:   README.md

➜  experimentation git:(master) ✗

這時候，變動進入了緩存區(Index)

但是我們突然發現我們改動錯了，其實我是想改動experimentation.txt文件。

方法一：我們當然可以再次修改experimentation和readme文件（刪除readme中的修改，給experimentation中添加“第一次修改”），然後再Add

方法二：我們想的可能是撤回之前的add操作，然後給experimentation中添加“第一次修改”，然後再次Add,那這樣的話，我們如何操作呢？

• 撤銷某個add文件:git reset HEAD <filename>

• 撤銷全部add文件:git reset HEAD .

➜  experimentation git:(master) ✗ git reset HEAD README.md
Unstaged changes after reset:
M       README.md
➜  experimentation git:(master) ✗ git status
On branch master
Your branch is up-to-date with 'origin/master'.
Changes not staged for commit:
  (use "git add <file>..." to update what will be committed)
  (use "git checkout -- <file>..." to discard changes in working directory)

        modified:   README.md

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

本地代碼已經add，已commit

將本地代碼多commit幾次,再來看下我們的提交log

• 方法一(推薦)：執行git revert <commitId>

撤回到指定的版本，包括文件和狀態。

• 方法二：執行git reset <commitId>

➜  experimentation git:(master) git reset 2a6c701
Unstaged changes after reset:
M       experimentation.txt
➜  experimentation git:(master) ✗ git status
On branch master
Your branch and 'origin/master' have diverged,
and have 4 and 6 different commits each, respectively.
  (use "git pull" to merge the remote branch into yours)
Changes not staged for commit:
  (use "git add <file>..." to update what will be committed)
  (use "git checkout -- <file>..." to discard changes in working directory)

        modified:   experimentation.txt

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

回退至指定的版本，區別如下