[git] Git undo changes in some files

While coding I added print statements into some files to keep track of what was going on.

When I am done, is it possible to revert changes in some files, but commit the file I actually worked on?

Say I added print in file A, but I modified file B. B is what I want to commit and A, I want to be set back to its old state.

man git-checkout: git checkout A

Yes;

git commit FILE

will commit just FILE. Then you can use

git reset --hard

to undo local changes in other files.

There may be other ways too that I don't know about...

edit: or, as NicDumZ said, git-checkout just the files you want to undo the changes on (the best solution depends on wether there are more files to commit or more files to undo :-)

git add B # Add it to the index
git reset A # Remove it from the index
git commit # Commit the index

Source : http://git-scm.com/book/en/Git-Basics-Undoing-Things

git checkout -- modifiedfile.java

1)$ git status

you will see the modified file

2)$git checkout -- modifiedfile.java

3)$git status

Why can't you simply mark what changes you want to have in a commit using "git add <file>" (or even "git add --interactive", or "git gui" which has option for interactive comitting), and then use "git commit" instead of "git commit -a"?

In your situation (for your example) it would be:

prompt> git add B
prompt> git commit

Only changes to file B would be comitted, and file A would be left "dirty", i.e. with those print statements in the working area version. When you want to remove those print statements, it would be enought to use

prompt> git reset A

or

prompt> git checkout HEAD -- A

to revert to comitted version (version from HEAD, i.e. "git show HEAD:A" version).