1. Version Control for the Uninitiated
A presentation by
David M. Doolin
for
WordPress Out Of (version) Control
Tuesday, May 31, 2011
6:00 PM
Automattic Lounge
711 The Embarcadero San Francisco, CA
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© 2011, Inventium Systems
Tuesday, May 31, 2011 1

2. Bona Fides
• Who am I?
• Consulting: Interdisciplinary science
and engineering software development.
• Inventium Systems: hibernating.
• Website In A Weekend: Pivoting out of
internet-space into local-space; working
with Tech Liminal, Oakland.
• Landing page: dool.in
I’ve used version control, starting with Concurrent Version System (CVS), since
1997. I’ve operated my own CVS repository, and I manage several remotely
hosted Subversion (SVN) repositories. I have too many projects on Github.
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3. Quick overview
• What is version control?
• Why you need version control.
• Version control tools
Subversion and Git.
• Learning version control.
All this in 12 minutes or less!
Disclaimer: this presentation was designed for entertainment purposes only, and abounds in vague generalizations, spurious analogies
and metaphors which don’t. Use common sense. Verify the information in this presentation from original sources. Do not cite. Thank you.
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4. What is version control?
• A suite of software methodologies.
• Keeps track of changes in files. Forever.
• Promotes collaboration between people across time and space.
• A philosophy for software engineering.
IMPORTANT: Version control is its own thing
No metaphor, analogy, figure of speech, long winded explanation or slide deck can
adequately convey modern version control. You have to do it for yourself.
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5. Almost 40 years of version control...
1974: Source Code Control System (SCCS). (Written in SNOBOL4!)
1982: Revision Control System (RCS).
1986: Concurrent Version System, (CVS).
2000: Subversion
2005: Git
When I first looked in to this version control thing, I asked a Real Hacker
“Which one, CVS or SCCS, should I learn?”
His reply: “Learn both, then choose for yourself.”
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6. Why use version control?
"It's a good idea." - Sarah Allen
• Collaboration with yourself & others across time.
• Collaboration with yourself & others across space.
• Automatic revisioning. You don’t have to dream up (and remember) some
hair-brained scheme for organizing revisions of all your files. (“What was the name
of that last file?”)
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7. Version Control - What you need to know
• Version control is leverage for collaboration. People can easily work
separated by geography and time zone.
• Leverage works 2 ways...
• Positive leverage: A good team becomes excellent. An excellent team
becomes phenomenal.
• Negative leverage: Teams with problems may find those problems getting
worse via version control.
• Communication is key: Version control enhances collaborator’s ability to
communicate.
Version control does NOT replace communication
Version control is not magic pixie dust.
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© 2011, Inventium Systems
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8. (CVS) Subversion at-a-glance
Beau Pete Ma.tt
Subversion operates from
a centralized repository
http://core.trac.wordpress.org/browser
• CVS is sort of like C, Which
makes Subversion (“a better CVS”)
sort of like C++.
• SVN: Use for any text or binary file:
LaTeX, WordPress source code,
images, this presentation, &c.
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9. Git at-a-glance
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10. Git after your first week
Unicorns courtesy of Cornify
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11. “Yes, but how does git feel...?”
Jazz lover’s guide to Git versus SVN
• SVN Closed hole flute: Easier to
play, sound quality good. Not as
cool.
• Git Open hole flute: Harder to
play, more flexible (microtones,
glissados, etc), sound quality
superb. Ineffably cooler.
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12. Centralized versus distributed repository
Git like distributed
Ma.tt cans of worms
You
Me
Pete
Me
SVN root
Image courtesy Coaching to Greatness
Ma.tt
SVN like the mighty oak
You Beau
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13. Some pros and cons
Pros Cons
• Branching (subtree checkout) remotely is • Global commits.
easier.
• Centralized repository.
• Easier to organize unrelated projects.
SVN Handles large numbers of unrelated • More prone to conflicts.
•
projects with ease. • Easier to bork local checkout.
• Only commit branch you’re working on.
• Local commits; reduces conflicts. • Project promiscuity.
• Deployment can be trivial, host git repo on • Must commit whole tree.
server, commit and push. Eliminates rsync. • Difficult to check out subtree
Git (this is a problem for WP theme
• Handles large complicated projects with and plugin development).
ease. (Designed for Linux kernel dev.)
• Nacin, Jaquith, Mall, etc. • Cannot commit stub (empty)
directory.
SVN evolved. Git was designed.
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14. Git Project Proliferation (not that cute)
Git’s distributed repository model can
induce large numbers of small
projects.
This is surprisingly inconvenient for
WordPress plugin and theme
development.
Be wary of project overindulgence. Starting with Git, It all seems so innocent
But projects seem to proliferate :( Creating projects is simple, easy & fun!
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15. Which one is better, Git or Subversion?
1st: There is no one-size-fits-all tool which is “better” than every other tool.
2d: Git and Subversion are going to be around a long, long time. The closer
you are to developers, the more likely you’re going to learn both anyway.
3d: If your main interest is WordPress development, learn Subversion now.
Yesterday. Seriously. Then learn Git.
4th: If you’re riding Rails, you probably already know you need to learn Git.
Mandatory.
My opinion: if you work with information, you won’t
escape learning version control. It’s inevitable.
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16. Bruce Lee’s Kung Fu guide to learning
version control
1. Novice stage: At first, version control is
just “version control.” Get a repository,
make some changes, save the changes.
2. Practitioner stage: Committing,
pushing, rebasing, rolling back,
branching, merging, moving, renaming...
the pros and cons of a dozen systems to
explore.
3. Mastery stage: Version control is just
version control. It’s easy and fun!
Image courtesy Wikipedia
Don’t wait. Start learning version control now.
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17. With a little help from...
so cool.
portable motivation.
‘Cause version control is a little like
voodoo, doncha know.
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18. Find this presentation on Slideshare
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