Merge branch 'ps/stash-push-pathspec-fix' into maint

"git stash push <pathspec>" did not work from a subdirectory at all.
Bugfix for a topic in v2.13

* ps/stash-push-pathspec-fix:
git-stash: fix pushing stash with pathspec from subdir

diff --combined t/t3903-stash.sh
index 3b4bed5c9ace3b9122380287c55b4130135018c7,d10ddb5b3580f02eab6f9e7694c186b0c3025e42..4046817d70a0ac1dd5b11a49c500896688a4f0b1
--- 1/t/t3903-stash.sh
--- 2/t/t3903-stash.sh
+++ b/t/t3903-stash.sh
@@@ -812,6 -812,22 +812,22 @@@ test_expect_success 'stash -- <pathspec
        test_path_is_file bar
  '
  
+ test_expect_success 'stash -- <pathspec> stashes in subdirectory' '
+       mkdir sub &&
+       >foo &&
+       >bar &&
+       git add foo bar &&
+       (
+               cd sub &&
+               git stash push -- ../foo
+       ) &&
+       test_path_is_file bar &&
+       test_path_is_missing foo &&
+       git stash pop &&
+       test_path_is_file foo &&
+       test_path_is_file bar
+ '
+ 
  test_expect_success 'stash with multiple pathspec arguments' '
        >foo &&
        >bar &&
@@@ -865,7 -881,7 +881,7 @@@ test_expect_success 'stash push -p wit
        git stash push -p foo >actual &&
        echo "No local changes to save" >expect &&
        git reset --hard HEAD~ &&
 -      test_cmp expect actual
 +      test_i18ncmp expect actual
  '
  
  test_expect_success 'stash push with pathspec shows no changes when there are none' '
@@@ -875,7 -891,7 +891,7 @@@
        git stash push foo >actual &&
        echo "No local changes to save" >expect &&
        git reset --hard HEAD~ &&
 -      test_cmp expect actual
 +      test_i18ncmp expect actual
  '
  
  test_expect_success 'stash push with pathspec not in the repository errors out' '