Diff topic branch + working copy changes?

So for a topic branch based on master, I can diff ONLY my changes on
the topic branch by doing this simple command:

$ git diff origin/master...

However, this does not include uncommitted working copy changes. To
work around this, I can do this instead:

$ git diff origin/master

(No three-dot notation above)

However this implies a ".." notation which will include changes on
master that have been made after I branched my topic (I use three-dot
to exclude those).

Is there a way I can do the first diff but also include working copy
changes? The reason I'm wanting to do this is because with difftool in
particular I like to make changes on the "right" side of each diff and
have those changes carry over to my working copy as edits I can
commit. This doesn't always work, especially if those same files are
already modified in my working copy but not committed.