#lang racket
(require rackunit rackunit/text-ui "2.rkt")

(define s0 (initialize (flat-contract integer?) =))
(define s2 (push (push s0 2) 1))

(run-tests
 (test-suite
  "stack"
  (test-true
   "empty"
   (is-empty? (initialize (flat-contract integer?) =)))
  (test-true "push" (stack? s2))
  (test-true
   "push exn"
   (with-handlers ([exn:fail:contract? (lambda _ #t)])
     (push (initialize (flat-contract integer?)) 'a)
     #f))
  (test-true "pop" (stack? (pop s2)))
  (test-equal? "top" (top s2) 1)
  (test-equal? "toppop" (top (pop s2)) 2)))