send-email: fix missing error message regression

Fix a regression with the "the editor exited uncleanly, aborting
everything" error message going missing after my
d21616c0394 (git-send-email: refactor duplicate $? checks into a
function, 2021-04-06).

I introduced a $msg variable, but did not actually use it. This caused
us to miss the optional error message supplied by the "do_edit"
codepath. Fix that, and add tests to check that this works.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 21 insertions, 2 deletions

diff --git a/t/t9001-send-email.sh b/t/t9001-send-email.sh
index 65b3035371..2acf389837 100755
--- a/t/t9001-send-email.sh
+++ b/t/t9001-send-email.sh
@@ -644,14 +644,33 @@ test_expect_success $PREREQ 'In-Reply-To with --chain-reply-to' '
 	test_cmp expect actual
 '
 
+test_set_editor "$(pwd)/fake-editor"
+
+test_expect_success $PREREQ 'setup erroring fake editor' '
+	write_script fake-editor <<-\EOF
+	echo >&2 "I am about to error"
+	exit 1
+	EOF
+'
+
+test_expect_success $PREREQ 'fake editor dies with error' '
+	clean_fake_sendmail &&
+	test_must_fail git send-email \
+		--compose --subject foo \
+		--from="Example <nobody@example.com>" \
+		--to=nobody@example.com \
+		--smtp-server="$(pwd)/fake.sendmail" \
+		$patches 2>err &&
+	grep "I am about to error" err &&
+	grep "the editor exited uncleanly, aborting everything" err
+'
+
 test_expect_success $PREREQ 'setup fake editor' '
 	write_script fake-editor <<-\EOF
 	echo fake edit >>"$1"
 	EOF
 '
 
-test_set_editor "$(pwd)/fake-editor"
-
 test_expect_success $PREREQ '--compose works' '
 	clean_fake_sendmail &&
 	git send-email \