Version Control Blog

Second chapter in O’Reilly book “Beautiful Code: Leading Programmers Explain How They Think” was written by Karl Fogel, and is called “Subversion’s Delta Editor: Interface as Ontology”. Karl has put this chapter online under the free license.

Read this chapter online: rants.org: “Beautiful Code Chapter Now Online”.

Short talk on Subversion misuse: “Subversion Worst Practices”.

Important opinions from Subversion developers:

Karl Fogel: “Subversion, decentralized version control, and the future”

Ben Collins-Sussman: “The Risks of Distributed Version Control”

C. Michael (Mike) Pilato, one of the main developers of Subversion, answers common questions about Subversion file locking feature.

The default version control model employed by Subversion is the copy-modify-merge model, where users asynchronously checkout personal working copies of a versioned directory, modify files inside that directory, and then commit their modifications, only worrying about conflicting changes made to the same file when they actually occur. Locking (sometimes referred to as “reserved checkouts”) allows Subversion users to step outside that default model and into the lock-modify-unlock model, in which multiple users preemptively serialize their commit access to a given file so that conflicts never occur.

Mike discusses pros and cons of file locking in context of Subversion; the exact mechanism for file locking (via svn:needs-lock property); and existing restrictions (only files could be locked, and not directories or branches).

Read at Subversion blog: From the Question Bin: Subversion Locking.

There is a discussion in comments to Aral Balkan’s Blog about Subversion clients for Mac OS X. Here is a list of all tools mentioned, slightly sorted by “popularity”:

• SCPlugin: allows to handle the Subversion working copy from Finder;
• Syncro SVN Client: multiplatform Subversion front-end, the UI looks a bit scary;
• svnX: open source GUI for most features of svn client binary;
• Subclipse: Eclipse Team Provider plug-in providing support for Subversion;
• SmartSVN: innovative multi-platform client for Subversion;
• ZigVersion: easy to use interface for Subversion;
• WebDAV autoversioning, briefly described in comment by zwetan;
• Command-line Subversion binaries from Martin Ott;

Many Mac users envy the TortoiseSVN client for Windows.

Launchpad.net is the system for collaboration, project management and code hosting for free software. It provides source repository hosting, bug tracker, a place to discuss project goals and features (called “blueprints”), translation management service, and the knowledge base. I won’t delve into details, but what caught my attention is that launchpad.net allows to make a read-only mirrors for Bazaar, Subversion and CVS repositories, and track code progress by subscribing to commits on any branch of that repository. Andy Wingo says:

Launchpad offers a web-based repository browser, including changesets, and offers the ability to subscribe to any branch it knows about. You get emails on distributed commits. This is a beautiful thing! Anyone who has worked with distributed VCS’s has probably had the feeling that they are seeing development through a keyhole, that there’s a whole world out there that’s not easily visible or comprehensible. Launchpad offers the possibility of tying together the various development branches out there in the wild in one place, effectively removing the last advantage of centralized version control.

Go to Launchpad.net. (via wingolog.org: “Launchpad”)

Small but useful post at Draconis Software Blog: “Backing up a Subversion repository”. We use svnadmin dump, but I guess that it becomes too slow for gigabyte-sized repositories (ours is ~400Mb).

Jonathan Snook posts a nice list of Subversion hosting services, including CVSDude, Wush.net, Hosted-project.com, CollabNet, DreamHost, Google, Gna, DejaVu, VersionShelf, ProjectLocker, and Springloops. I can add that TextDrive offers Subversion repositories with their (excellent) Ruby on Rails hosting plans. This is not a product placement. Read at: Jonathan Snook: “Hosted Subversion”

According to joint press-release, “CollabNet, Inc. the leading provider of collaborative software development solutions, and VA Software Corporation (Nasdaq: LNUX), today announced the execution and closing of an asset purchase transaction whereby CollabNet purchased the SourceForge Enterprise Edition business from VA Software in consideration for an equity ownership stake in CollabNet.” SourceForge Enterprise Edition supports CVS, Subversion and Perforce out of the box, and also provides possibility for integration with other SCM tools. Read more at Press Release: “CollabNet® and VA Software Sign Asset Purchase Agreement for Acquisition of SourceForge® Enterprise Edition Business by CollabNet” (via LWN.net)

Subversion 1.4.3 was released on 25th January 2007. A handful of bugfixes are included in this release. Read more in original announcement and detailed list of changes. Subversion homepage is at http://subversion.tigris.org/.