Subversion working copies 1.6 and earlier are no longer supported, and it is now required to use a command-line svn client for integration with Subversion.
Note that Subversion allows using higher working copy formats with an older server, so even if you have 1.6 svn server, you could use 1.7 or 1.8 working copy. If for some reasons you still need to use the 1.6 working copy format and cannot update it, please comment on the request.
In 2018.1 the SVNKit library has been removed from the IntelliJ platform, resulting in the above changes. There are several reasons for SVNKit removal, including the following:
- SVNKit is a third-party library and we cannot resolve some outstanding issues it has.
- SVNKit is used automatically when no command line client is installed, so a user could be forced to check out in an older format when checking out via the IntelliJ platform.
- SVN 1.6 is no longer supported by Apache Foundation, and the corresponding working copy format usage has also significantly decrease
Previous versions of IntelliJ IDEs supported Subversion copy formats 1.6 (and earlier), 1.7 and 1.8. Working with 1.6 and 1.7 was possible without using command-line svn client, via built-in SVNKit.
If your current working copy format is 1.6, after updating to IntelliJ 2018.1 you will need to upgrade the working copy to a higher version, using the Upgrade action on the Subversion Working Copies tab. You might also need to install a command-line svn client, e.g., command-line tools of TortoiseSVN on Windows. Using latest version is recommended.
SVNKit simply provides a Java implementation of SVN Integration, and standalone command line clients support all the same features as SVNKit does. They also share the same configs by default, so it should not force you to reconfigure much. If you have any issues setting up SVN integration to work with svn client, please contact technical support.
Library removal affects platform plugins, please see the Platform blog post for details.