[PATCH 0/1] Fix broken test with zsh as /bin/sh

[PATCH 0/1] Fix broken test with zsh as /bin/sh

[brian m. carlson]

macOS Catalina provides zsh as one of the three options for /bin/sh (the
other two being bash and dash).  Therefore, it's possible that people
will use zsh as /bin/sh and expect it to work when running Git and the
testsuite.

There are two things required for this to happen.  One is a patch to zsh
to make it run all items in a pipeline in a subshell in sh mode, just as
POSIX requires.  I've sent a patch[0] upstream to make that happen;
without that patch, multiple tests fail.

The other is this patch, which addresses a difference in behavior
between bash and dash, which strip out NUL bytes from the output of a
command substitution, and zsh, which does not.  Both behaviors are
permitted by POSIX, so this patch makes the test work in either case.

[0] https://www.zsh.org/mla/workers/2019/msg00960.html

brian m. carlson (1):
  t9001: avoid including non-trailing NUL bytes in variables

 t/t9001-send-email.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

[PATCH 1/1] t9001: avoid including non-trailing NUL bytes in variables

[brian m. carlson]

In this test, we have a command substitution whose output starts with a
NUL byte.  bash and dash strip out any NUL bytes from the output; zsh
does not.  As a consequence, zsh fails this test, since the command line
argument we use the variable in is truncated by the NUL byte.

POSIX says of a command substitution that if "the output contains any
null bytes, the behavior is unspecified," so all of the shells are in
compliance with POSIX.  To make our code more portable, let's avoid
prefacing our variables with NUL bytes and instead leave only the
trailing one behind.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
---
 t/t9001-send-email.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/t/t9001-send-email.sh b/t/t9001-send-email.sh
index 997f90b42b..51be0b8cd6 100755
--- a/t/t9001-send-email.sh
+++ b/t/t9001-send-email.sh
@@ -2066,7 +2066,7 @@ test_expect_success $PREREQ 'leading and trailing whitespaces are removed' '
 	TO1=$(echo "QTo 1 <to1@example.com>" | q_to_tab) &&
 	TO2=$(echo "QZto2" | qz_to_tab_space) &&
 	CC1=$(echo "cc1" | append_cr) &&
-	BCC1=$(echo "Q bcc1@example.com Q" | q_to_nul) &&
+	BCC1=$(echo " bcc1@example.com Q" | q_to_nul) &&
 	git send-email \
 	--dry-run \
 	--from="	Example <from@example.com>" \