So currently diff-mode outputs standard git patches, something like
@@ -8,6 +8,8 @@ -foo bar +baz
I.e. the + and - are part of the buffer text. Sometimes I would find it convenient if the +/- was displayed in the left FRINGE instead of as part of the output. So something like a
diff-mode-toggle-fringe-annotation function. I haven't found one however. Does it exist?