Modified files in a git branch are spilling over into another branch

Question

I am working on a git repository with a master branch and another the topic branch. I have switched to topic branch and modified a file. Now, if I switched to the master branch, that same file is shown as modified.

For example:

git status in git-build branch:

# On branch git-build # Changes to be committed: #   (use "git reset HEAD <file>..." to unstage) # #       modified:   cvsup_current # 

Switch to master branch

[root@redbull builder_scripts (git-build)]# git co master M       builder_scripts/cvsup_current Switched to branch "master" 

git status in master branch

[root@redbull builder_scripts (master)]# git status # On branch master # Changes to be committed: #   (use "git reset HEAD <file>..." to unstage) # #       modified:   cvsup_current # 

Why is that the file is shown as modified in the master branch even though it was modified in git-build branch?

My understanding was that the branches are independent of each other and when I change from one branch to another the changes do not "spill over" from one branch to another. So I am obviously missing something here.

Has anyone got a clue stick?

Answer 1

Why is that the file is shown as modified in master branch even though it was modified in git-build branch?

The key to remember is that the file was not modified in the git-build branch. It was only modified in your working copy.

Only when you commit are the changes put back into whichever branch you have checked out

Answer 2

If you want to temporarily store your changes to one branch while you go off to do work on another, you can use the git stash command. It's one of the amazing little unsung perks of using git. Example workflow:

git stash #work saved git checkout master #edit files git commit git checkout git-build git stash apply #restore earlier work 

git stash stores a stack of changes, so you can safely store multiple checkpoints. You can also give them names/descriptions. Full usage info here.