git blame && git fsck –lost-found

         git中把commit删了后，并不是真正的删除，而是变成了悬空对象（dangling commit）。我们只要把把这悬空对象（dangling commit）找出来，用git rebase也好，用git merge也行就能把它们给恢复。

这里最重要的一个命令就是：git fsck –lost-found 。

         如果你要查看文件的每个部分是谁修改的, 那么 git blame 就是不二选择. 只要运行'git blame [filename]', 你就会得到整个文件的每一行的详细修改信息:包括SHA串,日期和作者:

如何找回git 中丢失的提交(commit)

我们先创建一个用以实验的仓库，在里面创建了若干个提交和分支。
BTW：你可以直接把下面的命令复制到shell里执行。

mkdir recovery;cd recovery
git init
touch file
git add file
git commit -m "First commit"
echo "Hello World" > file
git add .
git commit -m "Greetings"
git branch cool_branch　
git checkout cool_branch
echo "What up world?" > cool_file
git add .
git commit -m "Now that was cool"
git checkout master
echo "What does that mean?" >> file


恢复已删除分支提交

现在repo里有两个branch

$ git branch
cool_branch
* master

存储当前仓库未提交的改动

$ git stash save "temp save"
Saved working directory and index state On master: temp save
HEAD is now at e3c9b6b Greetings

删除一个分支

$ git branch -D cool_branch
Deleted branch cool_branch (was 2e43cd5).

$ git branch
 * master

用git fsck --lost-found命令找出刚才删除的分支里面的提交对象。

$git fsck --lost-found
  dangling commit 2e43cd56ee4fb08664cd843cd32836b54fbf594a

用git show命令查看一个找到的对象的内容，看是否为我们所找的。

git show 2e43cd56ee4fb08664cd843cd32836b54fbf594a

  commit 2e43cd56ee4fb08664cd843cd32836b54fbf594a
  Author: liuhui <liuhui998[#]gmail.com>
  Date:   Sat Oct 23 12:53:50 2010 +0800

  Now that was cool

  diff --git a/cool_file b/cool_file
  new file mode 100644
  index 0000000..79c2b89
  --- /dev/null
  +++ b/cool_file
  @@ -0,0 +1 @@
  +What up world?

这个提交对象确实是我们在前面删除的分支的内容；下面我们就要考虑一下要如何来恢复它了。
使用git rebase　进行恢复

  $git rebase 2e43cd56ee4fb08664cd843cd32836b54fbf594a
  First, rewinding head to replay your work on top of it...
  Fast-forwarded master to 2e43cd56ee4fb08664cd843cd32836b54fbf594a.

现在我们用git log命令看一下，看看它有没有恢复:

  $ git log

  commit 2e43cd56ee4fb08664cd843cd32836b54fbf594a
  Author: liuhui <liuhui998[#]gmail.com>
  Date:   Sat Oct 23 12:53:50 2010 +0800

  Now that was cool

  commit e3c9b6b967e6e8c762b500202b146f514af2cb05
  Author: liuhui <liuhui998[#]gmail.com>
  Date:   Sat Oct 23 12:53:50 2010 +0800

  Greetings

  commit 5e90516a4a369be01b54323eb8b2660545051764
  Author: liuhui <liuhui998[#]gmail.com>
  Date:   Sat Oct 23 12:53:50 2010 +0800

  First commit


提交是找回来，但是分支没有办法找回来：

  liuhui@liuhui:~/work/test/git/recovery$ git branch
  * master

使用git merge　进行恢复

我们把刚才的恢复的提交删除

  $ git reset --hard HEAD^
  HEAD is now at e3c9b6b Greetings


再把刚删的提交给找回来：

  git fsck --lost-found
  dangling commit 2e43cd56ee4fb08664cd843cd32836b54fbf594a

不过这回我们用是合并命令进行恢复：

  $ git merge 2e43cd56ee4fb08664cd843cd32836b54fbf594a
  Updating e3c9b6b..2e43cd5
  Fast-forward
  cool_file |    1 +
  1 files changed, 1 insertions(+), 0 deletions(-)
  create mode 100644 cool_file

git stash的恢复

前面我们用git stash把没有提交的内容进行了存储，如果这个存储不小心删了怎么办呢？

当前repo里有的存储：
$ git stash list
stash@{0}: On master: temp save

把它们清空：
$git stash clear
liuhui@liuhui:~/work/test/git/recovery$ git stash list

再用git fsck –lost-found找回来：
$git fsck –lost-found
dangling commit 674c0618ca7d0c251902f0953987ff71860cb067

用git show看一下回来的内容对不对：

$git show 674c0618ca7d0c251902f0953987ff71860cb067

commit 674c0618ca7d0c251902f0953987ff71860cb067
Merge: e3c9b6b 2b2b41e
Author: liuhui <liuhui998[#]gmail.com>

Date:   Sat Oct 23 13:44:49 2010 +0800

    On master: temp save

diff --cc file
index 557db03,557db03..f2a8bf3
--- a/file
+++ b/file
@@@ -1,1 -1,1 +1,2 @@@
  Hello World
  ++What does that mean?

看起来没有问题，好的，那么我就把它恢复了吧：

$ git merge 674c0618ca7d0c251902f0953987ff71860cb067
Merge made by recursive.
 file |    1 +
  1 files changed, 1 insertions(+), 0 deletions(-)