June 24th, 2007
Bram Cohen announces:
Those of you who have used version control systems for a long time, or anything which has to diff extensively for that matter, know that once in a while they completely bungle a diff and give output which is, to put it charitably, extremely confusing.
Coming up with an algorithm which reliably gives good diffs is far from trivial, but is a problem which has now thankfully been solved. If you get the latest version of bazaar and use its diff utility it will give reasonable diff output on almost anything. All other version control systems (and I mean all others) should switch to using bazaar’s diff algorithm as a swap-in replacement, a change which has essentially no downside. (It also has better asymptotic runtime, and code which is easier to understand and debug.)
Later in comments he briefly explain new algorithm:
Instead of doing a longest common subsequence on everything, it does a longest common subsequence on lines which occur exactly once on both sides, then recurses between lines which got matched on that pass.
Read at: Bram Cohen: “The diff problem has been solved”.
I’d like to try it out when it becomes available for Subversion or Git.
Posted in Bazaar/bzr, Ideas | No Comments »
June 24th, 2007
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).
Posted in Subversion | No Comments »
June 24th, 2007
J. Paul Reed, a build engineer for Mozilla, writes an account on choosing the version control system for Mozilla development, instead of traditional CVS. The article is filled with digitally enhanced screenshots from Mortal Kombat II, illustrating the story.
Mercurial is current favorite (but not the winner).
Git, Mercurial, Bazaar, and Monotone were considered. Highlights:
- Git is inappropriate for cross-platform projects due to its UNIX-centric nature; same goes for Monotone;
- Mercurial had lots of initial troubles with import of Mozilla repository, which is huge and complicated;
- Bazaar imports well, but extremely slowly: more than a month for trunk-only part of Mozilla repository;
Read at: Version Control System Shootout Redux Redux.
See also: Mozilla Version Control System Requirements.
Posted in Bazaar/bzr, GIT, Mercurial, Monotone, SCM tools comparison, Use cases | No Comments »
June 24th, 2007
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”
Posted in Hosting, Subversion | No Comments »
May 19th, 2007
Ext3cow is a versioning file system for Linux 2.6.x. “It provides a time-shifting interface that allows a real-time and continuous view of the past. This allows users to access their file system as it appeared at any point in time.”
Main selling point for this seems to be the compatibility with various government data retention requirements, such as FISMA and Sarbanes-Oxley Act.
Read more at The ext3cow File System homepage.
Posted in Versioning filesystems, version control for ordinary users | No Comments »
May 19th, 2007
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)
Posted in CVS, Hosting, Perforce, Subversion | No Comments »
May 8th, 2007
If you thought that pre-commit hooks which validate the format of commit message are too strict — see a story about the ultimate commit strictness on our favourite Worse Than Failure. Notice also that this methods helps deal with potential merging conflicts.
Worse Than Failure: “Source Control Manager”.
Posted in Funny, Use cases | No Comments »
May 1st, 2007
Tor Norbye shows nice screenshots of local editing file history (with version diffing), and the brand new diff view. Note that the file itself is not under version control — diffs are against auto-saved version.
See: Tor Norbye: “Ruby Screenshot of the Week #6″. The smooth curves are very cool.
See also: Meld: open-source visual diff and merge tree for Gnome. Supports CVS, Subversion, Bazaar-ng and Mercurial.
Posted in visual diff | No Comments »
March 28th, 2007
“Open Source Development with CVS” by Karl Fogel and Moshe Bar is one of the obligatory books to mention here.
Of course, CVS is becoming somewhat irrelevant these days (except for the public project hosting services, where it prevails), but this book is of moderate size (368 pages), packed with useful information (if you still have to use CVS and wish to upgrade your knowledge somewhat), written by world-famous developers (Karl Fogel of CVS and Subversion fame, Moshe Bar of openMosix, Xen and KVM fames), and is available freely on the Internet (under the GNU GPL).
Book covers CVS basics, repository administration, and some advanced (for CVS world) features. It contains extensive CVS reference, has many tips and troubleshooting advices, and briefly describes various third-party tools which make the CVS more useful.
Read it online: Karl Fogel, Moshe Bar “Open Source Development with CVS”; download in PDF form; see the book’s official site.
Buy at Amazon: Open Source Development with CVS.
More books on version control and SCM: Version Control Blog Library.
Posted in Books, CVS | 1 Comment »
March 26th, 2007
Microsoft Patterns and Practices team has released first several topics as a part of Visual Studio 2005 Team System Guidance. This project will be the “single best repository of Visual Studio Team System guidance”, including practical scenario-based guidance for roles such as PMs, developers, architects, testers. It contains thoroughly engineered and tested set of recommendations, and it will be the single entry point for videos, roadmaps, and task-based how-tos. Particularly interesting part of this project is the Team Foundation Server Branching Guide.
This is an on-going work, and it gets announced in J. D. Meier’s blog as new parts appear:
(via Brian Harry’s Blog)
Posted in Microsoft Team Foundation, SCM features and concepts, branching and merging | No Comments »