# Copyright (c) 2005 Linus Torvalds
# Copyright (c) 2005 Junio C Hamano
+USAGE='[ --diff-options ] <ent>{0,2} [<path>...]'
+SUBDIRECTORY_OK='Yes'
+. git-sh-setup
+
rev=$(git-rev-parse --revs-only --no-flags --sq "$@") || exit
flags=$(git-rev-parse --no-revs --flags --sq "$@")
files=$(git-rev-parse --no-revs --no-flags --sq "$@")
-: ${flags:="'-M' '-p'"}
+# I often say 'git diff --cached -p' and get scolded by git-diff-files, but
+# obviously I mean 'git diff --cached -p HEAD' in that case.
+case "$rev" in
+'')
+ case " $flags " in
+ *" '--cached' "*)
+ rev='HEAD '
+ ;;
+ esac
+esac
+
+# If we do not have --name-status, --name-only nor -r, default to -p.
+# If we do not have -B nor -C, default to -M.
+case " $flags " in
+*" '--name-status' "* | *" '--name-only' "* | *" '-r' "* )
+ ;;
+*)
+ flags="$flags'-p' " ;;
+esac
+case " $flags " in
+*" '-"[BCM]* | *" '--find-copies-harder' "*)
+ ;; # something like -M50.
+*)
+ flags="$flags'-M' " ;;
+esac
case "$rev" in
?*' '?*' '?*)
- die "I don't understand"
+ usage
;;
?*' '^?*)
begin=$(expr "$rev" : '.*^.\([0-9a-f]*\).*') &&
end=$(expr "$rev" : '.\([0-9a-f]*\). .*') || exit
- cmd="git-diff-tree $flags $begin $end $files"
+ cmd="git-diff-tree $flags $begin $end -- $files"
;;
?*' '?*)
- cmd="git-diff-tree $flags $rev $files"
+ cmd="git-diff-tree $flags $rev -- $files"
;;
?*' ')
- cmd="git-diff-index $flags $rev $files"
+ cmd="git-diff-index $flags $rev -- $files"
;;
'')
- cmd="git-diff-files $flags $files"
+ cmd="git-diff-files $flags -- $files"
;;
*)
- die "I don't understand $*"
+ usage
;;
esac