This post goes over how to use use git reset to undo a commit or go back to a previous state:
Prerequisites
Let’s say you have the following commit history:
git log --oneline
e848206 current commit
0923435 previous commit
Soft
Reset the index and keep the changes in the staging area with git reset --soft:
git reset --soft HEAD~1 # or replace `HEAD~1` with the commit hash
The HEAD pointer will change to the previous commit:
git log HEAD --oneline --no-walk
0923435 previous commit
And the changes will appear as changes to be commmitted:
git status
On branch master
Changes to be committed:
(use "git reset HEAD <file>..." to unstage)
modified: file.txt
Mixed
Reset the index and keep the changes in the working tree with git reset --mixed:
git reset --mixed HEAD~1
Output:
Unstaged changes after reset:
M file.txt
This option is also the default mode.
Similarly, the HEAD pointer will be updated:
git log HEAD --oneline --no-walk
0923435 previous commit
And the changes will appear in the working tree:
git status
On branch 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: file.txt
no changes added to commit (use "git add" and/or "git commit -a")
Hard
Reset the index and discard the changes with git reset --hard:
git reset --hard HEAD~1
Output:
HEAD is now at 0923435 previous commit
As you can see, the changes are not kept:
git status
On branch master
nothing to commit, working tree clean
Final Note
What if you performed a reset but want to undo it?
You can undo it by going back to the previous reference update:
git reset HEAD@{1}
If you’re curious, you can see all your reference logs with reflog:
git reflog