如何在Git当前分支中获取最新的姓氏？

Question

For example, in a git worktree of Linux Kernel.

$ git checkout v2.6.6
$ git checkout v3.3

How to find the last head name or HASHID in current branch v3.3? In the example above, it should get v2.6.6 or the HASHID for v2.6.6.

Thanks.

Answer 1

Every time you move the head git records it in the reflog .

$ git reflog

If you were to run this command after the commands in your question, the old commit hash would be on the second line down and will reference the tag you were moving to.

For example

ff06760 HEAD@{0}: checkout: moving from 9b49c22462f5dd73ff18eacff5983f141f98cb82 to v3.3
9b49c22 HEAD@{1}: checkout: moving from ff06760cd0db8cef49915e68886c66c09b1cade1 to v2.6.6

Answer 2

Expanding on Blake Taylor's answer, the last HEAD position is always HEAD@{1} , but this type of revision specification is so much more powerful than that:

git checkout HEAD@{n} ;# checkout the nth prior position of HEAD
git checkout HEAD@{"1 hour ago"} ;# checkout HEAD an hour back
git checkout master@{"yesterday"} ;# checkout yesterday's master
git checkout master@{"1 week ago"} ;# checkout last week's
git checkout @{-1} ;# checkout the last branch checked out
git checkout @{-n} ;# checkout the nth last branch

and my personal favorite:

git checkout :/"<regex>" ;# checkout the youngest commit matching <regex>

... wait what? This syntax is awesome:

git checkout :/"Case 959" ;# see the state when we fixed case 959
git checkout :/"ct/topic" ;# checkout the state when 'ct/topic' was merged
git checkout :/"^Hotfix" ;# checkout the most recent commit that started 'Hotfix'

Knowing these refspecs makes navigating your history easy.