Subversion 1.5 Release Notes

Working Copy and Repository Format Changes

Due to certain improvements and bugfixes made to the working copy library, the version number of the working copy format has been incremented. This means that Subversion clients earlier than 1.5 will not be able to work with working copies produced by Subversion 1.5. Similarly, the repository format has changed as well, meaning that pre-1.5 Subversion tools that normally access a repository directly (e.g. svnserve, mod_dav_svn, svnadmin) won't be able to read a repository originally created by Subversion 1.5.

WARNING: if a Subversion 1.5 client encounters a pre-1.5 working copy, it will automatically upgrade the working copy format as soon as it touches it, making it unreadable by older Subversion clients. If you are using several versions of Subversion on your machine, you need to be careful about which version you use in which working copy, to avoid accidentally upgrading the working copy format. This "auto upgrade" feature, however, does not occur with the new repository format.

If you do accidentally upgrade a 1.4 (only) working copy, you can use this script to downgrade it back 1.4. See the FAQ for details, and run the script with the --help option for usage instructions.

Command Line Output Changes

Although the Subversion developers try hard to keep output from the command line programs compatible between releases, new information sometimes has to be added. This might break scripts that rely on the exact format of the output. In 1.5, the following changes have been made to the output:

XXX: Enumerate changes to output (e.g. for changelists).

• Conflict markers in files now match the file's defined eol-style.

Merge Tracking (client and server)

XXX

Sparse checkouts (client and server)

XXX: Described here.

Interactive Conflict Resolution (client)

Added support for interactive conflict resolution in the command line client, and a corresponding callback function in the client library. GUI clients can use the callback function to hook in a graphical conflict resolution program to the update/switch/merge sub-commands. Example command line output:

    $ svn up
    U    contrib/client-side/svnmerge/svnmerge_test.py
    Conflict discovered in 'contrib/client-side/svnmerge/svnmerge.py'.
    Select: (p)ostpone, (d)iff, (e)dit, (h)elp : h
      (p)ostpone - mark the conflict to be resolved later
      (d)iff     - show all changes made to merged file
      (e)dit     - change merged file in an editor
      (r)esolved - accept merged version of file
      (m)ine     - accept my version of file
      (t)heirs   - accept repository's version of file
      (l)aunch   - use third-party tool to resolve conflict
      (h)elp     - show this list

    Select: (p)ostpone, (d)iff, (e)dit, (h)elp : t
    G    contrib/client-side/svnmerge/svnmerge.py
    Updated to revision 25685.

This feature can be selectively disabled by using the --non-interactive option, or disabled permanently by setting '[miscellany] interactive-conflicts = no' in your run-time config file.

The API for interactive conflict resolution is exposed via a callback function and the following new data types:

• svn_wc_conflict_resolver_func_t, the callback API itself
• svn_wc_conflict_description_t, a description of the conflict passed to the callback
• svn_wc_conflict_action_t, the part of the conflict description indicating what the merge was trying to do
• svn_wc_conflict_reason_t, the part of the conflict description indicating the type of conflict
• svn_wc_conflict_result_t, returned by the callback as the result of any conflict resolution attempt

Clients provide their callback function to Subversion's libraries by setting it on the (new) conflict_func field of their svn_client_ctx_t, and may provide additional state to the callback via the corresponding conflict_baton field.

WebDAV transparent write-through proxy (server)

XXX: A mod_dav_svn feature activated using the SVNMasterURI directive in httpd.conf.

Cyrus SASL support for ra_svn and svnserve (client and server)

XXX: Described here.

Changelist support (client)

XXX: Described here.

Relative peg URLs in svn:externals

Two additions to the svn:externals feature

• The URLs may include peg specifications. Because the directory a URL refers to with and without a peg revision uses a different lookup and result in different contents, the current format from older versions of Subversion continues to not understand peg revisions. A new format is introduced to allow peg revisions in URLs.

  So the old format of

            foo             http://example.com/repos/zig
            foo/bar -r 1234 http://example.com/repos/zag
          

  does not support peg revisions. In fact, these following externals will not work unless there are directories named zig@HEAD and zag@HEAD:

            foo             http://example.com/repos/zig@HEAD
            foo/bar -r 1234 http://example.com/repos/zag@HEAD
          

  The new format moves the URL first followed by the directory the external is checked out or exported into

            http://example.com/repos/zig foo1
            -r 1234 http://example.com/repos/zag foo/bar1
            http://example.com/repos/zig@HEAD foo2
            -r 1234 http://example.com/repos/zag@HEAD foo/bar2
          

  peg specifications are allowed but not necessary.

• Up to Subversion 1.4, the URLs in an svn:externals specification must be absolute. Now they can be relative. Four different relative externals are supported.

  For the following example, assume we have two repositories at http://example.com/svn/repos-1 and http://example.com/svn/repos-2. We have a checkout of http://example.com/svn/repos-1/project1/trunk and the svn:external property is set on trunk.

  • ../
    Relative to the directory with the svn:external property. These URLs always begin with the string ../.

                  ../../project2/trunk common/project2/trunk
                

    This will extract http://example.com/svn/repos-1/project2/trunk into common/project2/trunk. The URL is relative to the directory with the svn:external, not the directory where the external is written to disk.
  • ^/
    Relative to the repository root.

                  ^/project2/trunk common/project2/trunk
                

    This will extract http://example.com/svn/repos-1/project2/trunk into common/project2/trunk.
    You can also refer to other repositories easily using repository root relative URLs:

                  ^/../repos-2/foo/trunk common/foo/trunk
                

    This will extract http://example.com/svn/repos-2/foo/trunk into common/foo/trunk
  • //
    Relative to the scheme. This copies the scheme of the checkout or export URL into the URL in the svn:external. It is useful when the same hostname must the accessed with different scheme's depending upon network location; i.e. clients in the intranet use http:// while external clients use svn+ssh://.

                  //example.com/svn/repos-1/project2/trunk common/project2/trunk
                

    This will extract http://example.com/svn/repos-1/project2/trunk into common/project2/trunk. If the working copy was checked out from svn+ssh://example.com/svn/repos-1/project1/trunk then this URL would be http://example.com/svn/repos-1/project1/trunk.
  • /
    Server root relative URLs. This copies the scheme and hostname from the checkout or export URL into the svn:external URL.

                  /svn/repos-1/project2/trunk common/project2/trunk
                

    This will extract http://example.com/svn/repos-1/project2/trunk into common/project2/trunk. If the working copy was checked out from svn+ssh://example.com/svn/repos-1/project1/trunk then this URL would be http://example.com/svn/repos-1/project1/trunk.

  Relative URLs are supported in the old svn:externals format that do not support peg revisions.

  When Subversion sees an svn:externals without an absolute URL it takes the first argument as a relative URL and the second as the target directory.

FSFS sharding

XXX: Useful for file systems which don't perform well with a large number of files in a directory -- see blog entry here.

Copy/move-related improvements (client and server)

The abilities and behavior of copy and move operations has improved significantly.

Cancellation improvements (client)

Clients operations are now significantly more responsive to cancellation (e.g. via control-c). In pre-1.5 releases, after directing an operation to stop, one sometimes had to wait for some time (e.g. while I/O occurred) before the operation would actually stop.

Command-line client improvements (client)

• A --use-merge-history option to adhere to Merge Tracking meta data has been added to the following sub-commands:
  • log
  • merge
• A --parents option to create intermediate directories has been added to the following sub-commands:
  • add
  • copy
  • move
  • mkdir
• A --keep-local option to retain paths locally has been added to the delete sub-command.

XXX: More...

API changes, improvements and language bindings (client and server)

If you develop a 3rd-party client application that uses Subversion APIs, you may want to take notice of the following changes and new APIs:

• svn_opt_parse_path() changes
  • Since Subversion 1.3, if a path or URL ends in an empty revision suffix '@', then the returned revision type would be different than an unprotected path or URL:
    • some/path/to/foo returns svn_opt_revision_unspecified
    • some/path/to/foo@ returns svn_opt_revision_base
    • http://example.com/some/path/to/foo returns svn_opt_revision_unspecified
    • http://example.com/some/path/to/foo@ returns svn_opt_revision_head
    Subversion 1.5 fixes this inconsistency, all the above paths and URLs return svn_opt_revision_unspecified.
  • Since Subversion 1.2, svn_opt_parse_path would always canonicalize the returned path or URL with svn_path_canonicalize, even though this is not documented in subversion/include/svn_opt.h. For the relative externals support, uncanonicalized paths need to be returned, otherwise scheme relative URLs, i.e. //example.com/some/path would be canonicalized to server root relative URLs /example.com/some/path. Users of this function now must ensure that they canonicalize the result of this function if they pass it to any other Subversion functions that expect a canonicalized path or URL.
• XXX: Enumerate specific new API additions (e.g. merge info retrieval?)
• APIs backing the new Command-line client improvements section have been added.
• Many APIs have been revised to newer versions.
• Language bindings expanded and improved

Easier to try out experimental ra_serf DAV access module (client)

Subversion 1.4 introduced the experimental ra_serf repository access module for accessing HTTP[S] DAV Subversion servers. This uses the serf library instead of the Neon library which the original DAV support uses. serf supports pipelined requests which may lead to better performance. However, Subversion 1.4 required you to choose which module to use for accessing DAV servers at build time, which made it difficult to find out which module performs better for your usage patterns.

Subversion 1.5 allows you to build both modules at the same time; you can choose which library to use on a global or host-by-host basis by setting the http-library variable in your run-time server configuration file (~/.subversion/servers). In recognition of the fact that both libraries are DAV clients, we have renamed ra_dav to ra_neon.

Other bug fixes (client and server)

The usual slew of heretofore-unreleased bug fixes, more than 40 overall. See the CHANGES file for full details.