Committing changes

Here's the process of commiting changes to the local repository:

1. Let's makes some changes:

   % echo "Hope you enjoy the tutorial." >> README
   % echo "\nTo cleanup the workspace:\n\nrm *.class" >> INSTALL
   

2. Run git status in the workspace to confirm that git picked up the changes.

   % git status
   # On branch master
   # 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
   #
   no changes added to commit (use "git add" and/or "git commit -a")
   

3. Despite there being changes, if you run git commit nothing should happen.

   % git commit -m "This shouldn't work"
   # On branch master
   # 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
   #
   no changes added to commit (use "git add" and/or "git commit -a")
   

4. You'll need to stage the changes for the commit via git add. Let's stage just the INSTALL change.

   % git add INSTALL
   % git status
   # 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:   README
   

5. It's important to note that you staged the change and not the file. Any more changes you make to INSTALL will not be staged.

   % echo "\nAnother change." >> INSTALL
   % git status
   # 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
   #
   

6. Now commit via git commit. This will open your $EDITOR and allow you to add a message. You can also add a message via -m <message> and skip opening the editor.

   % git commit -m "Adding clean instructions to INSTALL"
   [master 8e89ada] Adding clean instructions to INSTALL
    1 files changed, 4 insertions(+), 0 deletions(-)
   % git status
   # On branch master
   # Your branch is ahead of 'origin/master' by 1 commit.
   #
   # 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
   #
   no changes added to commit (use "git add" and/or "git commit -a")
   

7. Notice that when you run git status, it mentions Your branch is ahead of 'origin/master' by 1 commit. The committed change is now in your local repository but still needs to be pushed to the remote repository. See Pushing changes to origin/master.