DifferencesFromSubversion

This page is aimed at Subversion (SVN) users who want to know how Darcs differs from it.

Advantages of darcs over SVN

  • Every working copy of the repository is a fully functional repository whereas in SVN, there is one central repository and one or more working copies that need to access the repository for common operations.

  • Darcs behaves more gracefully when the server/central repository fails With Darcs, if your “server” gets messed up for whatever reason, your users can still exchange patches amongst themselves. Moreover, creating a new central repository is as easy as running darcs get from one of the working copies.

  • Darcs users can work offline and still record changes as they are made whereas SVN does not provide a way to record your work when you don’t have access to your server.

  • Darcs is simpler to setup You only have to install and configure one binary on each of your machines. On the other hand, at least svnadmin and svn are needed to start using Subversion.

  • Simple merging and branching A new branch is just another local copy of the repository. You can selectively move patches between branches, and to/from the server. In a lot of cases, merging requires no user input.

  • Darcs is more interactive, creating more efficient workflows Darcs is easy to learn and pleasant to use because it is interactive. As you record, push or pull patches, you are given the opportunity to review details, be selective, and create a workflow that suits you.

  • Darcs makes it easier to accept contributions from non-commiters E-mailing a patch is the usual alternative to directly committing into the project. With darcs, this process is fully automated, just use darcs send and you will be interactively prompted for which patches to send.

Unsupported features of SVN

  • Partial repository checkout Subversion allows you to check out working copies of a portion of a tree. You can check out only what you need and never see changes other users are making to other parts of the repository.

  • Support for file permissions and symlinks Subversion uses “svn:executable” and “svn:special” file properties to support executables and symlinks. Darcs currently doesn’t support arbitrary file properties, any special file permissions or symlinks (cross-platform support for the latter two would involve considerable amount of work). If you attempt to add a symlink, Darcs will issue a warning and will not add it.

  • keywords are informational strings that can be added to files managed by SVN. They look like this:

    $Id: File2.java,v 1.3 2004/06/02 17:30:42 JHunter Exp $

    Darcs intentionally doesn’t support this concept, since this implies modifying your source code.

Advantages of SVN over darcs

  • Better related tools and GUI Projects like TortoiseSVN makes adoption among less technically inclined or GUI dependent developers easier. Darcs isn’t as well integrated with popular web-based repository / development timeline / patch visualisation tools (on the other hand, see TracDarcs for a trac plugin and other related software ).

  • SVN is faster for large projects Darcs is currently falling behind when it comes to speed with large projects. Performance is one of our main concerns and we keep on enhancing this aspect of Darcs with each release (see our benchmarks).

  • Better handling of binary files Darcs can handle binary files but saves each version of a binary file as a complete file, whereas Subversion only stores the diff between versions of a binary. See issue1233 .

See also