Showing Revision 3 created 05/24/2016 by Udacity Robot.

1. Title:
   New - Keeping a Fork Up-To-Date
2. Description:

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   While you're making a contribution to
   the create your own adventure story, you
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   may find that your pull request can't
   be merged because of merge conflicts.
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   Here's how that could happen and
   how you could fix it.
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   Suppose you fork the original
   repository on GitHub, clone your fork,
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   then make a change in a new branch,
   and push that change to your fork.
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   In the meantime, someone else changes
   the original repository on GitHub.
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   If there are merge conflicts
   between their change and
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    your change, then your pull request will
    not be able to be automatically merged.
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    Since there's no way to resolve
    merge conflicts on the GitHub site,
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    you'll need to resolve the conflicts
    within the clone on your computer.
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    To do that, you'll need to get the
    conflicting changes from the original
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    repository into your local repository,
    which you can do by adding a remote.
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    Recall that you already have
    a remote set up called origin that
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    points to your fork.
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    But you'll still need to add a remote
    that points to the original repository.
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    And many people name
    this remote upstream.
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    Adding and fetching the upstream
    remote will add branches like
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    upstream/master into
    your local repository, so
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    that you can merge the upstream
    branch with your local branch.
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    For example, I created a pull request
    to add an option of stop, drop, and
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    roll to a page of the story
    where there was a fire.
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    In the meantime, though, another
    change was made to the same file to
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    add an option to turn on
    the chocolate sprinkler.
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    That change conflicts with mine, so
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    I need to resolve the conflicts
    before my pull request can be merged.
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    So in this diagram, this is the commit
    adding the chocolate sprinkler, and
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    also this one.
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    And my change was to add a stop,
    drop, and roll option.
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    These commits were the same
    in all the versions.
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    Since I created my change in
    a separate branch, I want to
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    make my master branch the same as
    the master in the original repository.
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    So, I'll run git pull upstream/master
    to update my master branch to
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    the latest commit from
    the original repository.
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    Then I'll merge the master branch
    into my changed branch, and
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    I'll push both the changed branch and
    the master branch to my fork.
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    I didn't need to push the master branch,
    but I thought it might be nice.
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    Now since this whole process only
    contains commands that you've
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    already learned, I want you to try
    doing this on your own before I
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    demonstrate how to do
    it on the command line.
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    As a reminder,
    the steps you'll need to carry out are,
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    first, add the original repository
    as a remote in your clone.
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    Next pull the master branch from
    the original repository into your
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    clone's master.
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    Merge the master branch into
    your change branch locally.
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    And resolve any merge conflicts.
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    And finally,
    push your change branch to your fork,
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    which will automatically
    update your pull request.
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    If you run into trouble,
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    I'll demonstrate how to carry out
    this process in the solution.
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    If you didn't run into this problem
    because your pull request was
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    merged without conflicts,
    I encourage you to get some practice by
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    making a new change and
    then not making a pull request for it.
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    Then you can wait for
    someone else to make a change and
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    then get some practice
    bringing your fork up to date.
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    Even if there are no merge conflicts,
    you can still get practice merging.
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    Once you've finished this process,
    check this box