tests: use 'test_must_be_empty' instead of 'test_cmp /dev/null <out>'

Using 'test_must_be_empty' is more idiomatic than 'test_cmp /dev/null
out', and its message on error is perhaps a bit more to the point.

This patch was basically created by running:

  sed -i -e 's%test_cmp /dev/null%test_must_be_empty%' t[0-9]*.sh

with the exception of the change in 'should not fail in an empty repo'
in 't7401-submodule-summary.sh', where it was 'test_cmp output
/dev/null'.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 3 insertions, 3 deletions

diff --git a/t/t3210-pack-refs.sh b/t/t3210-pack-refs.sh
index afa27ffe2d..112cbb0e62 100755
--- a/t/t3210-pack-refs.sh
+++ b/t/t3210-pack-refs.sh
@@ -127,7 +127,7 @@ test_expect_success 'explicit pack-refs with dangling packed reference' '
 	git reflog expire --expire=all --all &&
 	git prune --expire=all &&
 	git pack-refs --all 2>result &&
-	test_cmp /dev/null result
+	test_must_be_empty result
 '
 
 test_expect_success 'delete ref with dangling packed version' '
@@ -139,7 +139,7 @@ test_expect_success 'delete ref with dangling packed version' '
 	git reflog expire --expire=all --all &&
 	git prune --expire=all &&
 	git branch -d lamb 2>result &&
-	test_cmp /dev/null result
+	test_must_be_empty result
 '
 
 test_expect_success 'delete ref while another dangling packed ref' '
@@ -150,7 +150,7 @@ test_expect_success 'delete ref while another dangling packed ref' '
 	git reflog expire --expire=all --all &&
 	git prune --expire=all &&
 	git branch -d lamb 2>result &&
-	test_cmp /dev/null result
+	test_must_be_empty result
 '
 
 test_expect_success 'pack ref directly below refs/' '