t0040-parse-options: improve test coverage

diff --git a/t/t6002-rev-list-bisect.sh b/t/t6002-rev-list-bisect.sh
index 43ad7724845cd0e1523aadd60845f048a6b92ce5..3bf2759eaebd38bca5d37f624144436fc77828eb 100755 (executable)
--- a/t/t6002-rev-list-bisect.sh
+++ b/t/t6002-rev-list-bisect.sh
@@ -27,9 +27,9 @@ test_bisection_diff()
        # Test if bisection size is close to half of list size within
        # tolerance.
        #
-       _bisect_err=`expr $_list_size - $_bisection_size \* 2`
-       test "$_bisect_err" -lt 0 && _bisect_err=`expr 0 - $_bisect_err`
-       _bisect_err=`expr $_bisect_err / 2` ; # floor
+       _bisect_err=$(expr $_list_size - $_bisection_size \* 2)
+       test "$_bisect_err" -lt 0 && _bisect_err=$(expr 0 - $_bisect_err)
+       _bisect_err=$(expr $_bisect_err / 2) ; # floor
 
        test_expect_success \
        "bisection diff $_bisect_option $_head $* <= $_max_diff" \