submodule foreach: correct path display in recursive submodules

The `prefix` was put in front of the display path unconditionally.
This is wrong as any relative path computation would need to be at
the front, so include the prefix into the display path.

The new test replicates the previous test with the difference of executing
from a sub directory. By executing from a sub directory all we would
expect all displayed paths to be prefixed by '../'.

Prior to this patch the test would report
    Entering 'nested1/nested2/../nested3'
instead of the expected
    Entering '../nested1/nested2/nested3'

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Author: stefanbeller

git-submodule.sh

@@ -413,8 +413,8 @@ cmd_foreach()
 		die_if_unmatched "$mode"
 		if test -e "$sm_path"/.git
 		then
-			displaypath=$(relative_path "$sm_path")
-			say "$(eval_gettext "Entering '\$prefix\$displaypath'")"
+			displaypath=$(relative_path "$prefix$sm_path")
+			say "$(eval_gettext "Entering '\$displaypath'")"
 			name=$(git submodule--helper name "$sm_path")
 			(
 				prefix="$prefix$sm_path/"
@@ -434,7 +434,7 @@ cmd_foreach()
 					cmd_foreach "--recursive" "$@"
 				fi
 			) <&3 3<&- ||
-			die "$(eval_gettext "Stopping at '\$prefix\$displaypath'; script returned non-zero status.")"
+			die "$(eval_gettext "Stopping at '\$displaypath'; script returned non-zero status.")"
 		fi
 	done
 }

t/t7407-submodule-foreach.sh

@@ -177,6 +177,26 @@ test_expect_success 'test messages from "foreach --recursive"' '
 	test_i18ncmp expect actual
 '
 
+cat > expect <<EOF
+Entering '../nested1'
+Entering '../nested1/nested2'
+Entering '../nested1/nested2/nested3'
+Entering '../nested1/nested2/nested3/submodule'
+Entering '../sub1'
+Entering '../sub2'
+Entering '../sub3'
+EOF
+
+test_expect_success 'test messages from "foreach --recursive" from subdirectory' '
+	(
+		cd clone2 &&
+		mkdir untracked &&
+		cd untracked &&
+		git submodule foreach --recursive >../../actual
+	) &&
+	test_i18ncmp expect actual
+'
+
 cat > expect <<EOF
 nested1-nested1
 nested2-nested2