| Subject: | not tracking tied array/hash/scalar values |
| Date: | Fri, 24 Jul 2009 06:39:08 +1000 |
| To: | bug-Test-Weaken [...] rt.cpan.org |
| From: | Kevin Ryde <user42 [...] zip.com.au> |
When Test::Weaken looks at a tied array or hash, I believe there's no
actual scalars which are elements or values and therefore no underlying
storage to track in that case.
I think the way the current code takes proberefs like \($aref->[0]) ends
up, on a tied array, with a ref to a new magical scalar thingie which
does calls to FETCH and STORE. The little program below suggests you
get a brand new magical thingie on every single ref, so there isn't even
a shared one that might be checked against leaks, instead the taking of
the proberef brings a new one into existance.
The upshot would be that Test::Weaken could save some work on tied
arrays, hashes, and probably tied scalars too, by not attempting to
track the elements of those. It should still fetch the values and track
(I think) and descend into them as usual, just that \($aref->[0])
doesn't refer to any actual storage in the case of a tie.
#!/usr/bin/perl
use strict;
use warnings;
package MaiTai;
sub TIEARRAY {
return bless { abc => 123,
def => 456 }, __PACKAGE__;
}
sub FETCHSIZE {
return 1;
}
sub FETCH {
return 999;
}
package main;
my $aref;
{
my @array;
tie @array, 'MaiTai';
$aref = \@array;
}
my @refs;
foreach (1..5) {
push @refs, \($aref->[0]);
}
foreach my $ref (@refs) {
print "$ref\n";
}
print "refs 0 and 1 are ",
($refs[0] == $refs[1] ? "equal" : "NOT equal"), "\n";
exit 0;