test "$#" = 3 && { prereq=$1; shift; } || prereq=
test "$#" = 2 ||
error "bug in the test script: not 2 or 3 parameters to test_expect_equal"
test "$#" = 3 && { prereq=$1; shift; } || prereq=
test "$#" = 2 ||
error "bug in the test script: not 2 or 3 parameters to test_expect_equal"