[Rd] Why R should never move to git

[Duncan Murdoch]

Lately I've been doing some work with the manipulateWidget package, 
which lives on Github at 
https://github.com/rte-antares-rpackage/manipulateWidget/.  Last week I 
found a bug, so being a good community member, I put together a patch.

Since the package lives on Github, I followed instructions to put 
together a "pull request":

- I forked the main branch to my own Github account as 
<https://github.com/dmurdoch/manipulateWidget>.

- I checked out my fork into RStudio.

- I fixed the bug, and submitted the pull request 
<https://github.com/rte-antares-rpackage/manipulateWidget/pull/47>.

Then I felt good about myself, and continued on with my work.  Today I 
tracked down another bug, unrelated to the previous one.  I know enough 
about git to know that I shouldn't commit this fix to my fork, because 
it would then become part of the previous pull request.

So I created a branch within my fork, and committed the change there. 
But Github provides no way to create a pull request that only includes 
the new stuff!  Every attempt I made would have included everything from 
both bug fixes.

I've read online about creating a new branch based on the master copy, 
and "cherry picking" just the final change:  but all the instructions 
I've tried so far have failed.

Okay, I know the solution:  I need to burn the whole thing down (to 
quote Jenny Bryan).  I'll just create a new fork, and put the new bug 
fix in a branch there.

I can't!  I don't know if this is a Git restriction or a Github 
restriction, but it won't let me create a new fork without deleting the 
old one.  I don't know if deleting the previous fork would also delete 
the previous PR, so I'm not going to do this.

This is ridiculous!  It is such an easy concept:  I want to take the 
diff between my most recent commit and the one before, and send that 
diff to the owners of the master copy.  This should be a trivial (and it 
is in svn).

Git and Github allow the most baroque arrangements, but can't do this 
simple task.  That's an example of really bad UI design.

Duncan Murdoch