Stashing changes

Say that you're working on a feature and you have several uncommited changes. Along comes a frantic PM telling you to switch gears and fix a mission critical bug. You look at your changes and realize they're not commit worthy. This gives you two options: say you're in the middle of something or use git stash.

1. Let's create three changes and stage one of them.

   % echo "I'm going to stash this" >> README
   % echo "I'm going to stash this" >> INSTALL
   % git add INSTALL
   % echo "I'm going to stash this too" >> INSTALL
   

   Running git status should show us that we have some changes

   # On branch master
   # Changes to be committed:
   #   (use "git reset HEAD <file>..." to unstage)
   #
   #   modified:   INSTALL
   #
   # Changed but not updated:
   #   (use "git add <file>..." to update what will be committed)
   #   (use "git checkout -- <file>..." to discard changes in working
   #   directory)
   #
   #   modified:   INSTALL
   #   modified:   README
   #
   

2. To stash these changes run git stash.

   % git stash
   Saved working directory and index state WIP on master: 94ae280 Adding clean instructions to INSTALL
   HEAD is now at 94ae280 Adding clean instructions to INSTALL
   % git status
   # On branch master
   nothing to commit (working directory clean)
   

3. Let's create and check in the "bug fix".

   % echo "Bug fix." >> README
   % git commit -am "Fixing the bug."
   

4. Now pop the changes (the pop will not work if you have uncommitted changes).

   % git stash pop
   Auto-merging README
   CONFLICT (content): Merge conflict in README
   % git status
   # On branch master
   # Your branch is ahead of 'origin/master' by 1 commit.
   #
   # Changes to be committed:
   #   (use "git reset HEAD <file>..." to unstage)
   #
   #   modified:   INSTALL
   #
   # Unmerged paths:
   #   (use "git reset HEAD <file>..." to unstage)
   #   (use "git add/rm <file>..." as appropriate to mark resolution)
   #
   #   both modified:      README
   #
   

   Since the stash included changes on README and we commited a change on README, a conflict arose. You can resolve it via your favorite merge tool.

   % cat README
   Hey this a test for git. Welcome, to git.
   <<<<<<< Updated upstream
   Bug fix.
   =======
   I'm going to stash this
   >>>>>>> Stashed changes
   

   Also notice that the pop did not preserve the changes to INSTALL that were staged and unstaged. All changes to a file will be combined and left unstaged (in this case they were staged, not sure why).