howto make svn diff look like diff?

Question

There's another question: howto make diff look like svn diff? but I want the exact opposite. I'm trying to get svn diff to display with < and >

The obvious answer would be:

svn diff --diff-cmd /usr/bin/diff  file

but when I do that I get

/usr/bin/diff: illegal option -- L

So I do this

svn diff --diff-cmd /usr/bin/echo  file

to see what's going on. and it spits out all this, which I can see why diff doesn't like it....

-u -L file (revision 11371) -L file   (working copy) .svn/text-base/file.svn-base file

So... how do I make svn actually use another program for diffing?

Answer 1

You seem to have a version of diff installed on your system that is too old or incompatible with how svn wants to call it. In my system, the -L option is defined thusly:

   -L label
   --label=label
          Use label instead of the file name in the context format and unified format headers.

So you should just use a diff command that removes that flag before passing it along to your system's diff. I do something similar to add a custom set of options to diff (and add colours), in my .subversion/configs file:

diff-cmd=/home/ether/bin/svndiff-w

...where the program is just a simple shell script:

#!/bin/bash
diff=/usr/bin/colordiff
args="-u -wi -U 6 --new-file"    
exec ${diff} ${args} "$@"

This is discussed in more detail in the manual under Using External Differencing and Merge Tools.