Some parts of Subversion 1.8 integration are already implemented. There is still a number of issues in YouTrack. But the table below is aimed to provide high level overview of current feature implementation status.
Planned but not implemented yet
Feature has known currently not implemented parts
File conflicts handling/resolving
Tree conflicts handling/resolving
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Issues with highlight integrated
Upgrade working copy
Nested working copies
Authentication: file, svn, http
https two-way should be supported, https one-way - trusting to not valid certificate should be enhanced
Works ok, if no interaction with ssh client is required (for instance, public key with no passphrase or ssh agent is used).
Proxies configured in IDEA