Add prefix oriented completions for diff and format-patch commands.

diff --git a/contrib/completion/git-completion.bash b/contrib/completion/git-completion.bash
index 791e30f6d78b06429f239defc76aaa0d09db4e09..4d81963b1d00b1b4e874330a9e5933111f491def 100755 (executable)
--- a/contrib/completion/git-completion.bash
+++ b/contrib/completion/git-completion.bash
@@ -639,7 +639,9 @@ _git_diff ()
                        --find-copies-harder --pickaxe-all --pickaxe-regex
                        --text --ignore-space-at-eol --ignore-space-change
                        --ignore-all-space --exit-code --quiet --ext-diff
-                       --no-ext-diff"
+                       --no-ext-diff
+                       --no-prefix --src-prefix= --dst-prefix=
+                       "
                return
                ;;
        esac
@@ -696,6 +698,7 @@ _git_format_patch ()
                        --full-index --binary
                        --not --all
                        --cover-letter
+                       --no-prefix --src-prefix= --dst-prefix=
                        "
                return
                ;;
@@ -865,7 +868,7 @@ _git_rebase ()
                return
                ;;
        --*)
-               __gitcomp "--onto --merge --strategy"
+               __gitcomp "--onto --merge --strategy --interactive"
                return
        esac
        __gitcomp "$(__git_refs)"