Dynamic scope creation without a plugin?

I'd like to be able to run an inspection limited to files that have been changed between the git branch I am on, and another branch.

The list of changed files can be retreived by (OSX environment, possibly *ix as well):

`git diff --stat-width=1000 --name-only [current git branch]..[target git branch] | xargs -I '{}' echo "$(git rev-parse --show-toplevel)/{}"`

Replacing "[current git branch]" and "[target git branch]" with things like "feature/my_neat_feature" and "develop".

Is this kind of dynamic scope completion possible without developing a custom plugin?  I.E.: is there a way to get scope to call a shell command to get a list of files to include?