test-suite/tests/guardians.test

   1 ;;;; guardians.test --- test suite for Guile Guardians     -*- scheme -*-
   2 ;;;; Jim Blandy <jimb@red-bean.com> --- July 1999
   3 ;;;;
   4 ;;;;    Copyright (C) 1999 Free Software Foundation, Inc.
   5 ;;;;
   6 ;;;; This program is free software; you can redistribute it and/or modify
   7 ;;;; it under the terms of the GNU General Public License as published by
   8 ;;;; the Free Software Foundation; either version 2, or (at your option)
   9 ;;;; any later version.
  10 ;;;;
  11 ;;;; This program is distributed in the hope that it will be useful,
  12 ;;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 ;;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 ;;;; GNU General Public License for more details.
  15 ;;;;
  16 ;;;; You should have received a copy of the GNU General Public License
  17 ;;;; along with this software; see the file COPYING.  If not, write to
  18 ;;;; the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  19 ;;;; Boston, MA 02111-1307 USA
  20
  21 ;;; These tests make some questionable assumptions.
  22 ;;; - They assume that a GC will find all dead objects, so they
  23 ;;;   will become flaky if we have a generational GC.
  24 ;;; - They assume that objects won't be saved by the guardian until
  25 ;;;   they explicitly invoke GC --- in other words, they assume that GC
  26 ;;;   won't happen too often.
  27
  28 (gc)
  29
  30 (define g1 (make-guardian))
  31 (define not-g1-garbage (list 'not-g1-garbage))
  32 (g1 not-g1-garbage)
  33 (g1 (list 'g1-garbage))
  34 (pass-if "g1-garbage not collected yet" (equal? (g1) #f))
  35 (gc)
  36 (pass-if "g1-garbage saved" (equal? (g1) '(g1-garbage)))
  37
  38 ;;; Who guards the guardian?
  39 (gc)
  40 (define g2 (make-guardian))
  41 (g2 (list 'g2-garbage))
  42 (define g3 (make-guardian))
  43 (g3 (list 'g3-garbage))
  44 (g3 g2)
  45 (pass-if "g2-garbage not collected yet" (equal? (g2) #f))
  46 (pass-if "g3-garbage not collected yet" (equal? (g3) #f))
  47 (set! g2 #f)
  48 (gc)
  49 (let ((seen-g3-garbage #f)
  50       (seen-g2 #f)
  51       (seen-something-else #f))
  52   (let loop ()
  53     (let ((saved (g3)))
  54       (if saved
  55           (begin
  56             (cond
  57              ((equal? saved '(g3-garbage)) (set! seen-g3-garbage #t))
  58              ((procedure? saved) (set! seen-g2 saved))
  59              (else (set! seen-something-else #t)))
  60             (loop)))))
  61   (pass-if "g3-garbage saved" seen-g3-garbage)
  62   (pass-if "g2-saved" seen-g2)
  63   (pass-if "nothing else saved" (not seen-something-else))
  64   (pass-if "g2-garbage saved" (and (procedure? seen-g2)
  65                                    (equal? (seen-g2) '(g2-garbage)))))