標準配布の runit/assert.rb (など)は、[RAA:RubyUnit] の互換ライブラリ で、Test::Unit により実装されています。
assert(condition[, message])assert_equal(expected, actual[, message])assert_equals(expected, actual[, message])assert_operator(obj1, op, obj2[, message])assert_equal_float(expected, actual, e[, message])assert_same(expected, actual[, message])assert_send(obj, method, *args)assert_nil(obj[, message])assert_not_nil(obj[, message])assert_respond_to(method, obj[, message])assert_kind_of(c, obj[, message])assert_instance_of(c, obj[, message])assert_match(str, re[, message])assert_matches(str, re[, message])assert_not_match(str, re[, message])assert_exception(exception[, message]) { ... }assert_no_exception(exceptions, ...[, message]) { ... }assert_fail(message)