Enhancement to also use the external diff tool for new and deleted files.

[David Ingamells]

Aaron Bentley wrote:
> The --using functionality was originally provided by a plugin called
> difftools: https://code.launchpad.net/~sward-dev/bzr-difftools/trunk
>
> My implementation doesn't have nearly the same rich functionality, but
> at least it's in core.  The original had special cases for a variety of
> different tools, and distinguished between per-file tools and whole-tree
> tools.
>
> So I think it's worth pursuing an implementation where diff --using is
> unchanged, but your particular tool is handled better.
>
> Aaron
>
>   

Aaron,
I suspect that it would be a thankless task trying to maintain a list of 
various diff tools and how to call them. Wouldn't it be more sense to 
add a new option to diff --using to control this? Something like
     -diffstyle visual|stdout|tree|...

Where the default is "stdout" and is the current method and "visual" 
tries to give all changes it can to a visual diff tool (e.g. meld).