stash: Don't fail if work dir contains file named 'HEAD'

When performing a plain "git stash" (without --patch), git-diff would fail
with "fatal: ambiguous argument 'HEAD': both revision and filename". The
output was piped into git-update-index, masking the failed exit status.
The output is now sent to a temporary file (which is cleaned up by
existing code), and the exit status is checked. The "HEAD" arg to the
git-diff invocation has been disambiguated too, of course.

In patch mode, "git stash -p" would fail harmlessly, leaving the working
dir untouched. Interactive adding is fine, but the resulting tree was
diffed with an ambiguous 'HEAD' argument.

Use >foo (no space) when redirecting output.

In t3904, checks and operations on each file are in the order they'll
appear when interactively staging.

In t3905, fix a bug in "stash save --include-untracked -q is quiet": The
redirected stdout file was considered untracked, and so was removed from
the working directory. Use test path helper functions where appropriate.

Signed-off-by: Jonathon Mah <me@JonathonMah.com>
Acked-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 29 insertions, 18 deletions

diff --git a/t/t3904-stash-patch.sh b/t/t3904-stash-patch.sh
index 781fd71681..70655c1848 100755
--- a/t/t3904-stash-patch.sh
+++ b/t/t3904-stash-patch.sh
@@ -7,7 +7,8 @@ test_expect_success PERL 'setup' '
 	mkdir dir &&
 	echo parent > dir/foo &&
 	echo dummy > bar &&
-	git add bar dir/foo &&
+	echo committed > HEAD &&
+	git add bar dir/foo HEAD &&
 	git commit -m initial &&
 	test_tick &&
 	test_commit second dir/foo head &&
@@ -17,47 +18,57 @@ test_expect_success PERL 'setup' '
 	save_head
 '
 
-# note: bar sorts before dir, so the first 'n' is always to skip 'bar'
+# note: order of files with unstaged changes: HEAD bar dir/foo
 
 test_expect_success PERL 'saying "n" does nothing' '
+	set_state HEAD HEADfile_work HEADfile_index &&
 	set_state dir/foo work index &&
-	(echo n; echo n) | test_must_fail git stash save -p &&
-	verify_state dir/foo work index &&
-	verify_saved_state bar
+	(echo n; echo n; echo n) | test_must_fail git stash save -p &&
+	verify_state HEAD HEADfile_work HEADfile_index &&
+	verify_saved_state bar &&
+	verify_state dir/foo work index
 '
 
 test_expect_success PERL 'git stash -p' '
-	(echo n; echo y) | git stash save -p &&
-	verify_state dir/foo head index &&
+	(echo y; echo n; echo y) | git stash save -p &&
+	verify_state HEAD committed HEADfile_index &&
 	verify_saved_state bar &&
+	verify_state dir/foo head index &&
 	git reset --hard &&
 	git stash apply &&
-	verify_state dir/foo work head &&
-	verify_state bar dummy dummy
+	verify_state HEAD HEADfile_work committed &&
+	verify_state bar dummy dummy &&
+	verify_state dir/foo work head
 '
 
 test_expect_success PERL 'git stash -p --no-keep-index' '
-	set_state dir/foo work index &&
+	set_state HEAD HEADfile_work HEADfile_index &&
 	set_state bar bar_work bar_index &&
-	(echo n; echo y) | git stash save -p --no-keep-index &&
-	verify_state dir/foo head head &&
+	set_state dir/foo work index &&
+	(echo y; echo n; echo y) | git stash save -p --no-keep-index &&
+	verify_state HEAD committed committed &&
 	verify_state bar bar_work dummy &&
+	verify_state dir/foo head head &&
 	git reset --hard &&
 	git stash apply --index &&
-	verify_state dir/foo work index &&
-	verify_state bar dummy bar_index
+	verify_state HEAD HEADfile_work HEADfile_index &&
+	verify_state bar dummy bar_index &&
+	verify_state dir/foo work index
 '
 
 test_expect_success PERL 'git stash --no-keep-index -p' '
-	set_state dir/foo work index &&
+	set_state HEAD HEADfile_work HEADfile_index &&
 	set_state bar bar_work bar_index &&
-	(echo n; echo y) | git stash save --no-keep-index -p &&
+	set_state dir/foo work index &&
+	(echo y; echo n; echo y) | git stash save --no-keep-index -p &&
+	verify_state HEAD committed committed &&
 	verify_state dir/foo head head &&
 	verify_state bar bar_work dummy &&
 	git reset --hard &&
 	git stash apply --index &&
-	verify_state dir/foo work index &&
-	verify_state bar dummy bar_index
+	verify_state HEAD HEADfile_work HEADfile_index &&
+	verify_state bar dummy bar_index &&
+	verify_state dir/foo work index
 '
 
 test_expect_success PERL 'none of this moved HEAD' '