;;;; guardians.test --- test suite for Guile Guardians -*- scheme -*-
;;;; Jim Blandy <jimb@red-bean.com> --- July 1999
;;;;
-;;;; Copyright (C) 1999, 2001, 2006 Free Software Foundation, Inc.
+;;;; Copyright (C) 1999, 2001, 2006, 2014 Free Software Foundation, Inc.
;;;;
-;;;; This program is free software; you can redistribute it and/or modify
-;;;; it under the terms of the GNU General Public License as published by
-;;;; the Free Software Foundation; either version 2, or (at your option)
-;;;; any later version.
+;;;; This library is free software; you can redistribute it and/or
+;;;; modify it under the terms of the GNU Lesser General Public
+;;;; License as published by the Free Software Foundation; either
+;;;; version 3 of the License, or (at your option) any later version.
;;;;
-;;;; This program is distributed in the hope that it will be useful,
+;;;; This library is distributed in the hope that it will be useful,
;;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
-;;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-;;;; GNU General Public License for more details.
+;;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+;;;; Lesser General Public License for more details.
;;;;
-;;;; You should have received a copy of the GNU General Public License
-;;;; along with this software; see the file COPYING. If not, write to
-;;;; the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
-;;;; Boston, MA 02110-1301 USA
+;;;; You should have received a copy of the GNU Lesser General Public
+;;;; License along with this library; if not, write to the Free Software
+;;;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
;;; These tests make some questionable assumptions.
+;;;
;;; - They assume that a GC will find all dead objects, so they
;;; will become flaky if we have a generational GC.
+;;;
+;;; - More generally, when a weakly referenced object doesn't disappear as
+;;; expected, it's hard to tell whether that's because of a guardian bug of
+;;; because a reference to it is being held somewhere, e.g., one some part
+;;; of the stack that hasn't been overwritten. Thus, most tests cannot
+;;; fail, they can just throw `unresolved'. We try hard to clear
+;;; references that may have been left on the stacks (see "clear refs left
+;;; on the stack" lines).
+;;;
;;; - They assume that objects won't be saved by the guardian until
;;; they explicitly invoke GC --- in other words, they assume that GC
;;; won't happen too often.
-(use-modules (test-suite lib)
- (ice-9 documentation)
- (ice-9 weak-vector))
-
+(define-module (test-guardians)
+ :use-module (test-suite lib)
+ :use-module (ice-9 documentation)
+ :use-module (ice-9 weak-vector))
+\f
;;;
;;; miscellaneous
;;;
(pass-if "g3-garbage saved" (or seen-g3-garbage (throw 'unresolved)))
(pass-if "g2-saved" (or (procedure? seen-g2) (throw 'unresolved)))
(pass-if "nothing else saved" (not seen-something-else))
+
+ ;; FIXME: The following test fails because the guardian for `g2-garbage'
+ ;; disappared from the weak-car guardian list of `g2-garbage' right before
+ ;; `g2-garbage' was finalized (in `finalize_guarded ()'). Sample session
+ ;; (compiled with `-DDEBUG_GUARDIANS'):
+ ;;
+ ;; guile> (define g (make-guardian))
+ ;; guile> (let ((g2 (make-guardian)))
+ ;; (format #t "g2 = ~x~%" (object-address g2))
+ ;; (g2 (string-copy "foo"))
+ ;; (g g2))
+ ;; g2 = 81fde18
+ ;; guile> (gc)
+ ;; finalizing guarded 0x827f6a0 (1 guardians)
+ ;; guardian for 0x827f6a0 vanished
+ ;; end of finalize (0x827f6a0)
+ ;; finalizing guarded 0x81fde18 (1 guardians)
+ ;; end of finalize (0x81fde18)
+
(pass-if "g2-garbage saved" (or (and (procedure? seen-g2)
(equal? (seen-g2)
(list (string-copy
(let ((g (make-guardian)))
(gc)
(g (cons #f #f))
+ (cons 'clear 'stack) ;; clear refs left on the stack
(if (not (eq? (g) #f))
(throw 'unresolved)
(begin
(gc)
(g (cons #f #f))
(g (cons #t #t))
+ (cons 'clear 'stack) ;; clear refs left on the stack
(if (not (eq? (g) #f))
(throw 'unresolved)
(begin
(let ((g (make-guardian)))
(gc)
(g (cons #f #f))
+ (cons 'clear 'stack) ;; clear refs left on the stack
(if (not (eq? (g) #f))
(throw 'unresolved)
(begin
(gc)
(let ((p (cons #f #f)))
(g p)
- (vector-set! v 0 p))
+ (weak-vector-set! v 0 p)
+ (set! p #f)) ;; clear refs left on the stack
(if (not (eq? (g) #f))
(throw 'unresolved)
(begin
(gc)
(let ((p (cons #f #f)))
(g p)
- (vector-set! v 0 p))
+ (weak-vector-set! v 0 p)
+ (set! p #f)) ;; clear refs left on the stack
(begin
(gc)
(if (not (equal? (g) (cons #f #f)))
(throw 'unresolved)
(begin
(gc)
- (or (not (vector-ref v 0))
+ (or (not (weak-vector-ref v 0))
(throw 'unresolved))))))))
(with-test-prefix "guarding weak containers"
(pass-if "element of guarded weak vector gets collected"
(let ((g (make-guardian))
- (v (weak-vector (cons #f #f))))
+ (v (weak-vector #f)))
+ ;; Note: We don't pass `(cons #f #f)' as an argument to `weak-vector'
+ ;; otherwise references to it are likely to be left on the stack.
+ (weak-vector-set! v 0 (cons #f #f))
+
(g v)
(gc)
- (if (equal? (vector-ref v 0) (cons #f #f))
+ (if (equal? (weak-vector-ref v 0) (cons #f #f))
(throw 'unresolved)
#t))))
(gc)
(let ((p (cons #f #f)))
(g p)
- (g p))
+ (g p)
+ (set! p #f)) ;; clear refs left on the stack
(if (not (eq? (g) #f))
(throw 'unresolved)
(begin
(gc)
(let ((p (cons #f #f)))
(g p)
- (h p))
+ (h p)
+ (set! p #f)) ;; clear refs left on the stack
(if (not (eq? (g) #f))
(throw 'unresolved)
(begin
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