Subversion CLI default text editor on Linux - linux

Question

While there is no shortage of information on how to set a text editor for the Subversion Command Line Interface to use (see here, here, and here for example), I can't figure out where my local system is getting the text editor information from.
On my system, when I perform an svn commit, it opens vim for a commit message. Since this is what I want, I never really thought about it. This has always just worked. However, recently a co-worker was trying to commit, and it failed with an error saying the editor was not set. I never went out of my way to set an editor, so I am very confused about this.
I am running Ubuntu 12.04 and I have compiled and installed the Subversion CLI client version 1.8.10 from source code. Previous to that, I was using whatever Ubuntu's Canonical system installed with apt-get install subversion.
The Using External Editors section of the Subversion Book states the following possibilities for setting the text editor:
--editor-cmd command-line option
SVN_EDITOR environment variable
editor-cmd runtime configuration option
VISUAL environment variable
EDITOR environment variable
Possibly, a fallback value built into the Subversion libraries (not present in the official builds)
I have investigated these places and have not found how the default text editor is set on my computer:
Not using --editor-cmd option when committing
SVN_EDITOR environment variable not set
editor-cmd is not set in either my ~/.subversion/config, nor in /etc/subversion/config. Both of these files exist, but the line is commented out.
VISUAL environment variable not set
EDITOR environment variable not set
I'm downloading the official repository, so there should be no fallback.
There must be another place where the default can be set. Does anybody know?
Edit: There was a suggestion that Subversion might be calling /usr/bin/editor, and this is not set up on my co-worker's machine. I discovered that /usr/bin/editor is set up the same on both my system and my co-worker's system.

Answer 1

When you download the source directly (and build it - assuming you have the build dependencies met) you specify (or you can omit it) the default fallback editor. Normally source builds are done with something like this on Ubuntu (assume I have extracted/downloaded the subversion 1.8.10 source from here):
./configure
make
sudo make install
Notice the ./configure command above doesn't specify any options. The defaults will install to the prefix /usr/local . Prior to issuing those commands (on Ubuntu 12.04) I ran sudo apt-get build-dep subversion . I then did the commands above to build and install. I made sure that options 1-5 (In the OPs question) were not satisfied and then tried to commit a change to a repository. I got this as a response:
svn: E205007: Commit failed (details follow):
svn: E205007: Could not use external editor to fetch log message; consider setting the $SVN_EDITOR environment variable or using the --message (-m) or --file (-F) options
svn: E205007: None of the environment variables SVN_EDITOR, VISUAL or EDITOR are set, and no 'editor-cmd' run-time configuration option was found
Since I didn't remove the official Ubuntu subversion I had to run mine as /usr/local/bin/svn to make sure I was using the one I built. I could have used sudo apt-get remove subversion to remove the official one as well just to make sure.
Now if one runs these commands to rebuild the source:
make clean
./configure --with-editor=/usr/bin/editor
make
sudo make install
One should find that if options 1 to 5 are not satisfied and this version of subversion is run it should default to running whatever /usr/bin/editor points to. On Ubuntu that will depend on what alternative is being used.
So when Ubuntu does an official build where does their fallback editor come from? I went to the 12.04 source repository for subversion at this link . On the right hand side I downloaded the diff file subversion_1.6.17dfsg-3ubuntu3.4.diff.gz . I opened up the diff file Ubuntu uses and scrolling down you can find they use this set of ./configure options (flags):
confflags := \
--prefix=/usr \
--libdir=$(libdir) \
--mandir=\$${prefix}/share/man \
--with-apr=/usr \
--with-apr-util=/usr \
--with-neon=/usr \
--with-serf=/usr \
--with-berkeley-db=:::db \
--with-sasl=/usr \
--with-editor=/usr/bin/editor \
--with-ruby-sitedir=/usr/lib/ruby \
--with-swig=/usr \
--with-kwallet \
--with-gnome-keyring
The bold entry shows that they use /usr/bin/editor as their fallback.
I have built subversion 1.8.10 from source on Ubuntu 12.04 and got the expected behavior. This suggests one of these possibilities:
On one of the systems the options 1 through 5 is actually met.
One version of subversion was built with the --with-editor configure flag (either directly or indirectly). The fallback would point to whatever the --with-editor configure flag was set to.
On one of the systems the wrong version of subversion is being run. One possibility is that the official subversion on Ubuntu is in fact being used. If that is the case it was built to use /usr/bin/editor as a fallback.
On one of your systems you have an alias (or equivalent) for svn that specifies an editor. Aliases would be specified in a startup script like ~/.bashrc, ~/.bash_profile, /etc/bash.bashrc for example.

Answer 2

I think the normal way to specify this on Linux and other Unix-like systems, is to set the VISUAL environment variable (for GUI editors) or the EDITOR variable (for editors running in a terminal).

Answer 3

Try this:
update-alternatives --display editor

Answer 4

Run strings on your svn binary to see if it mentions Vim or any related env vars inside.
Also committing under strace -f may reveal something.

Answer 5

Set this in your .bashrc file.
Don't forget to "source .bashrc" or reopen terminal.
export SVN_EDITOR='vim'