[PATCH] submodule foreach: Added in --post-order=<command> and adjusted code per Jens Lehmann's suggestions

[eacousineau <eacousineau@gmail.com>]

Signed-off-by: eacousineau <eacousineau@gmail.com>
---
I see what you meant by the extra variables, so I've fixed that so the
original flags aren't needed with recursion. Also updated it to not
print the entering command if there is only a post-order command.

Examples:

$ git submodule foreach --recursive --post-order 'echo Goodbye' "echo \"'ello\""
Entering 'b'
'ello
Entering 'b/d'
'ello
Leaving 'b/d'
Goodbye
Leaving 'b'
Goodbye
Entering 'c'
'ello
Leaving 'c'
Goodbye

$ git submodule foreach --recursive --post-order :
Leaving 'b/d'
Leaving 'b'
Leaving 'c'

 git-submodule.sh | 31 ++++++++++++++++++++++++++-----
 1 file changed, 26 insertions(+), 5 deletions(-)

diff --git a/git-submodule.sh b/git-submodule.sh
index 79bfaac..e08a724 100755
--- a/git-submodule.sh
+++ b/git-submodule.sh
@@ -11,7 +11,7 @@ USAGE="[--quiet] add [-b <branch>] [-f|--force] [--name <name>] [--reference <re
    or: $dashless [--quiet] deinit [-f|--force] [--] <path>...
    or: $dashless [--quiet] update [--init] [--remote] [-N|--no-fetch] [-f|--force] [--rebase] [--reference <repository>] [--merge] [--recursive] [--] [<path>...]
    or: $dashless [--quiet] summary [--cached|--files] [--summary-limit <n>] [commit] [--] [<path>...]
-   or: $dashless [--quiet] foreach [--recursive] <command>
+   or: $dashless [--quiet] foreach [--recursive] [--post-order <command>] <command>
    or: $dashless [--quiet] sync [--recursive] [--] [<path>...]"
 OPTIONS_SPEC=
 . git-sh-setup
@@ -449,6 +449,15 @@ cmd_foreach()
 		--recursive)
 			recursive=1
 			;;
+		--post-order)
+			test "$#" = "1" && usage
+			post_order="$2"
+			shift
+			;;
+		--post-order=*)
+			# Will skip empty commands
+			post_order=${1#*=}
+			;;
 		-*)
 			usage
 			;;
@@ -471,7 +480,9 @@ cmd_foreach()
 		die_if_unmatched "$mode"
 		if test -e "$sm_path"/.git
 		then
-			say "$(eval_gettext "Entering '\$prefix\$sm_path'")"
+			enter_msg="$(eval_gettext "Entering '\$prefix\$sm_path'")"
+			leave_msg="$(eval_gettext "Leaving '\$prefix\$sm_path'")"
+			die_msg="$(eval_gettext "Stopping at '\$sm_path'; script returned non-zero status.")"
 			name=$(module_name "$sm_path")
 			(
 				prefix="$prefix$sm_path/"
@@ -479,13 +490,23 @@ cmd_foreach()
 				# we make $path available to scripts ...
 				path=$sm_path
 				cd "$sm_path" &&
-				eval "$@" &&
+				if test $# -gt 0 -o -z "$post_order"
+				then
+					say "$enter_msg" &&
+					eval "$@" || die "$die_msg"
+				fi &&
 				if test -n "$recursive"
 				then
-					cmd_foreach "--recursive" "$@"
+					# subshell will use parent-scoped values
+					cmd_foreach "$@"
+				fi &&
+				if test -n "$post_order"
+				then
+					say "$leave_msg" &&
+					eval "$post_order" || die "$die_msg"
 				fi
 			) <&3 3<&- ||
-			die "$(eval_gettext "Stopping at '\$sm_path'; script returned non-zero status.")"
+			die "$die_msg"
 		fi
 	done
 }
-- 
1.8.2.1.390.gd4ee029