[PATCH v2 0/4] refactor duplicate $? checks into a function + improve errors

There was a silly error in v1 noted by Junio. In practice we didn't hit that "die $msg if $die" in system_or_msg(), but it didn't belong there.

I see 1/2 of v1 of this series was merged to "next". I'm sending the full thing anyway, but presumably just 3-4 will be picked up. They apply cleanly on "next".

I added two patches at the end to improve the error output, the first two patches in both v1 and v2 just reproduced the current output bug-for-bug, but I've now made it more sensible.

Ævar Arnfjörð Bjarmason (4):
  git-send-email: replace "map" in void context with "for"
  git-send-email: refactor duplicate $? checks into a function
  git-send-email: test full --validate output
  git-send-email: improve --validate error output

 git-send-email.perl   | 45 +++++++++++++++++++++++++++----------------
 t/t9001-send-email.sh | 35 +++++++++++++++++++++++++--------
 2 files changed, 55 insertions(+), 25 deletions(-)

Range-diff:
1:  bea11504a67 = 1:  e37b861f239 git-send-email: replace "map" in void context with "for"
2:  f4bace5607c ! 2:  f236f083e36 git-send-email: refactor duplicate $? checks into a function
    @@ git-send-email.perl: sub format_2822_time {
     +sub system_or_msg {
     +	my ($args, $msg) = @_;
     +	system(@$args);
    -+	return unless (($? & 127) || ($? >> 8));
    ++	my $signalled = $? & 127;
    ++	my $exit_code = $? >> 8;
    ++	return unless $signalled or $exit_code;
     +
    -+	die $msg if $msg;
     +	return sprintf(__("failed to run command %s, died with code %d"),
    -+		       "@$args", $? >> 8);
    ++		       "@$args", $exit_code);
     +}
     +
     +sub system_or_die {
    @@ git-send-email.perl: sub validate_patch {
     -			$hook_error = "rejected by sendemail-validate hook"
     -				if system($validate_hook, $target);
     +			if (my $msg = system_or_msg([$validate_hook, $target])) {
    -+				# TODO Use $msg and emit exit code on
    -+				# hook failures?
     +				$hook_error = __("rejected by sendemail-validate hook");
     +			}
      			chdir($cwd_save) or die("chdir: $!");
-:  ----------- > 3:  15b59c226d4 git-send-email: test full --validate output
-:  ----------- > 4:  a1edceb4913 git-send-email: improve --validate error output