When cloning a sub-tree of an svn repo, arc diff is unaware of it, and assumes the local root as the actual root.
```lang=shell
seth@luca:~/tmp/d2$ pwd
/home/seth/tmp/d2
seth@luca:~/tmp/d2$ svn info
Path: .
Working Copy Root Path: /home/seth/tmp/d2
URL: svn+ssh://sshannin@secure.phabricator.com/diffusion/SVNTEST/dir2
Relative URL: ^/dir2
Repository Root: svn+ssh://sshannin@secure.phabricator.com/diffusion/SVNTEST
Repository UUID: 5a5cce42-fd4b-48a3-bcdc-3d0876698e76
Revision: 2
Node Kind: directory
Schedule: normal
Last Changed Author: sshannin
Last Changed Rev: 2
Last Changed Date: 2015-08-14 11:55:47 -0700 (Fri, 14 Aug 2015)
seth@luca:~/tmp/d2$ seq 100 > lines
seth@luca:~/tmp/d2$ svn add lines
seth@luca:~/tmp/d2$ arc diff
seth@luca:~/tmp/d2$ arc commit
```
----
Original description:
See D13902 for reference.
I ran the following commands:
# `seq 100 > lines`
# `svn add lines`
# `arc diff`
# `arc commit`
After the commit, an extra diff was created and attached to the revision. It indicated the full diff.
More concretely, the following 3 links all who the same diff:
https://secure.phabricator.com/D13902
https://secure.phabricator.com/D13902?vs=on&id=33558
https://secure.phabricator.com/D13902?vs=33558&id=33559
I would expect either
- Only one diff to be shown (no actual changes when I committed)
- An empty diff between the middle and final revision (third link)