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