Is there a way to recover from an accidental "svn revert"?

There is a solution... go to your recycle bin you'll find there the latest version of the deleted file. Tortoise "throwing" to the recycle bin every file that it revert.

No, (absolutely) NO.

If you say to Subversion it should revert a file, all changes are gone by the wind.

Only your memory can get them back.

Exception: New files you had added, will only lose their status "added", but the file will remain in this directory, only status is unknown("?")

Platform / Software exception: Using TortoiseSVN on Windows, Revert first throws the files into Recycle Bin and then reverts them. You can dig into the Recycle Bin to recover the files.

Not really Subversion specific, but if you're working with Eclipse, you can try your luck in the local history.

Now, something a little bit more Subversion specific: if you don't want to make a branch for every change you do, you can keep a couple of trunk checked out locally (trunk-modif-1, trunk-modif-2...). Each "modification" is done on a separate tree and you only need to keep a list of which check out correspond to which modification.

Or you could use Git locally but I never tried it.

Recently did this mistake of not committing new file changes (about 10) onto SVN and they all vanished because of my silly mistake. But what saved me was the windows "Restore previous versions" option in the context menu. Phew that was a relief and lesson learnt.

You can't recover the files, if you are using svn command-line client.

But you can recover them, if you are using TortoiseSVN as your svn client. TortoiseSVN will automatically move them to your Recycle Bin. You can restore them from there after an accidental revert.

This is a configurable option in TortoiseSVN. It is under Settings -> Dialog 1 -> Use recycle bin when reverting.

By default it is checked, which means files are moved to recycle bin. If you want(mostly you don't care to disable this. If you have a reason, please let me also know)

If you are using InteliJ then you are a lucky person. On the top menu, you have a Version Control option, and under it you will find local history option, where you will find all the history for selected file, including all the operation you did with that file (update,commit, revert ).

Good luck, Arkde

Also if you have reverted your .NET code (.cs files etc) and you've built your application before revert but after you've made changes, you could recover changes from assembly file using any of the reflector tools to view code.

I was extremely lucky to find a local change log of the file (Local Revisions) in the history browser in Eclipse. I had been inspecting the differences one by one and I had made a couple of saves on the file before overwriting.

I reverted solution (Visual Studio + AnkhSVN ) and lose changes of few files. I can't find the file in the recycle bin.

BUT: I recovered my losing files with Handy Recovery, i.e. SVN just delete my files on reverting.

Use any data recovery software to recovery reverted files(like trial Handy Recovery)

No, SVN does not keep a log or backup (although there is a solution for TortoiseSVN noted in the other answers).

But in case someone is browsing the answers and did not notice this comment in the OP's question:

"Fortunately in this case I had done an "svn diff > temp.txt" before leaving work on Friday, and the temp.txt file was still on my hard drive, so I was able to feed that file into "patch" and recover my lost changes."

I imagine it is a common paradigm to do 'svn diff' BEFORE you do an 'svn revert'. If you get in the habit of doing this, even if the diff is just echoed to the terminal, you've at least got one possible avenue to recover your lost changes.