ref_transaction_commit(): do not capitalize error messages

Our convention is for error messages to start with a lower-case
letter.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

refs.c

@@ -3922,7 +3922,7 @@ int ref_transaction_commit(struct ref_transaction *transaction,
 				? TRANSACTION_NAME_CONFLICT
 				: TRANSACTION_GENERIC_ERROR;
 			reason = strbuf_detach(err, NULL);
-			strbuf_addf(err, "Cannot lock ref '%s': %s",
+			strbuf_addf(err, "cannot lock ref '%s': %s",
 				    update->refname, reason);
 			free(reason);
 			goto cleanup;
@@ -3945,7 +3945,7 @@ int ref_transaction_commit(struct ref_transaction *transaction,
 				 * write_ref_to_lockfile():
 				 */
 				update->lock = NULL;
-				strbuf_addf(err, "Cannot update the ref '%s'.",
+				strbuf_addf(err, "cannot update the ref '%s'.",
 					    update->refname);
 				ret = TRANSACTION_GENERIC_ERROR;
 				goto cleanup;

t/t1400-update-ref.sh

@@ -519,7 +519,7 @@ test_expect_success 'stdin create ref works with path with space to blob' '
 test_expect_success 'stdin update ref fails with wrong old value' '
 	echo "update $c $m $m~1" >stdin &&
 	test_must_fail git update-ref --stdin <stdin 2>err &&
-	grep "fatal: Cannot lock ref '"'"'$c'"'"'" err &&
+	grep "fatal: cannot lock ref '"'"'$c'"'"'" err &&
 	test_must_fail git rev-parse --verify -q $c
 '
 
@@ -555,7 +555,7 @@ test_expect_success 'stdin update ref works with right old value' '
 test_expect_success 'stdin delete ref fails with wrong old value' '
 	echo "delete $a $m~1" >stdin &&
 	test_must_fail git update-ref --stdin <stdin 2>err &&
-	grep "fatal: Cannot lock ref '"'"'$a'"'"'" err &&
+	grep "fatal: cannot lock ref '"'"'$a'"'"'" err &&
 	git rev-parse $m >expect &&
 	git rev-parse $a >actual &&
 	test_cmp expect actual
@@ -688,7 +688,7 @@ test_expect_success 'stdin update refs fails with wrong old value' '
 	update $c  ''
 	EOF
 	test_must_fail git update-ref --stdin <stdin 2>err &&
-	grep "fatal: Cannot lock ref '"'"'$c'"'"'" err &&
+	grep "fatal: cannot lock ref '"'"'$c'"'"'" err &&
 	git rev-parse $m >expect &&
 	git rev-parse $a >actual &&
 	test_cmp expect actual &&
@@ -883,7 +883,7 @@ test_expect_success 'stdin -z create ref works with path with space to blob' '
 test_expect_success 'stdin -z update ref fails with wrong old value' '
 	printf $F "update $c" "$m" "$m~1" >stdin &&
 	test_must_fail git update-ref -z --stdin <stdin 2>err &&
-	grep "fatal: Cannot lock ref '"'"'$c'"'"'" err &&
+	grep "fatal: cannot lock ref '"'"'$c'"'"'" err &&
 	test_must_fail git rev-parse --verify -q $c
 '
 
@@ -899,7 +899,7 @@ test_expect_success 'stdin -z create ref fails when ref exists' '
 	git rev-parse "$c" >expect &&
 	printf $F "create $c" "$m~1" >stdin &&
 	test_must_fail git update-ref -z --stdin <stdin 2>err &&
-	grep "fatal: Cannot lock ref '"'"'$c'"'"'" err &&
+	grep "fatal: cannot lock ref '"'"'$c'"'"'" err &&
 	git rev-parse "$c" >actual &&
 	test_cmp expect actual
 '
@@ -930,7 +930,7 @@ test_expect_success 'stdin -z update ref works with right old value' '
 test_expect_success 'stdin -z delete ref fails with wrong old value' '
 	printf $F "delete $a" "$m~1" >stdin &&
 	test_must_fail git update-ref -z --stdin <stdin 2>err &&
-	grep "fatal: Cannot lock ref '"'"'$a'"'"'" err &&
+	grep "fatal: cannot lock ref '"'"'$a'"'"'" err &&
 	git rev-parse $m >expect &&
 	git rev-parse $a >actual &&
 	test_cmp expect actual
@@ -1045,7 +1045,7 @@ test_expect_success 'stdin -z update refs fails with wrong old value' '
 	git update-ref $c $m &&
 	printf $F "update $a" "$m" "$m" "update $b" "$m" "$m" "update $c" "$m" "$Z" >stdin &&
 	test_must_fail git update-ref -z --stdin <stdin 2>err &&
-	grep "fatal: Cannot lock ref '"'"'$c'"'"'" err &&
+	grep "fatal: cannot lock ref '"'"'$c'"'"'" err &&
 	git rev-parse $m >expect &&
 	git rev-parse $a >actual &&
 	test_cmp expect actual &&