How to perform the TFS-equivalent of 'Undo pending changes'
How do I perform the equivalent of the TFS 'Undo pending changes' in Git, on one or multiple files?
That basically means to do these steps:
- Undo changes on disk
- Resetting any changes Git has discovered
- Getting the latest changes on the file from Git
It would be good to know the differences (if there are any) in commands for doing this if you've (1) just changed it on disk, without adding it, but also when you've (2) done the add-command and for a bonus, (3) even when you have commit the change.
Answer
For 1 and 2, all you need to do is:
git stash -u #same effect as git reset --hard, but can be undone
this will throw away any changes. Be careful if you use reset. Read up on manipulating the index and the permutations of the hard, soft and mixed options with the reset and checkout. The progit book explains this in detail: http://progit.org/2011/07/11/reset.html
For 3,
git reset --hard HEAD^
but would be better to issue a git stash -u before this - just in case you have pending changes.
This will reset the current branch to the parent of the current commit. Look up "tree-ish" online. ^ and ~N after a reference will allow you to point to any reachable points in the history of that reference. To understand how history is tracked in git, "Git for computer scientists" explains the Directed Acyclic Graph well: http://eagain.net/articles/git-for-computer-scientists/
To get individual files from the state of the current commit (ie, throw away changes), you can use checkout
git checkout HEAD -- <a list of files>
If you issued the last reset command above in error, you're not in trouble. Git keeps track of where the branches used to point in the reflog.
git reflog
will list you the history. You can see in that output how to reference each, so:
git reset --hard HEAD@{1}
will reset the branch to where it used to be 1 change before.
To add, if you want to wipe ignored files and untracked files, you can wipe with this:
git clean -xdf