package DBICTest::Util::LeakTracer;
use warnings;
use strict;
use Carp;
use Scalar::Util qw/isweak weaken blessed reftype refaddr/;
use DBICTest::Util 'stacktrace';
use base 'Exporter';
our @EXPORT_OK = qw/populate_weakregistry assert_empty_weakregistry/;
my $refs_traced = 0;
my $leaks_found;
my %reg_of_regs;
sub populate_weakregistry {
my ($weak_registry, $target, $slot) = @_;
croak 'Expecting a registry hashref' unless ref $weak_registry eq 'HASH';
croak 'Target is not a reference' unless length ref $target;
$slot ||= (sprintf '%s%s(0x%x)', # so we don't trigger stringification
(defined blessed $target) ? blessed($target) . '=' : '',
reftype $target,
refaddr $target,
);
if (defined $weak_registry->{$slot}{weakref}) {
if ( refaddr($weak_registry->{$slot}{weakref}) != (refaddr $target) ) {
print STDERR "Bail out! Weak Registry slot collision: $weak_registry->{$slot}{weakref} / $target\n";
exit 255;
}
}
else {
$refs_traced++;
weaken( $weak_registry->{$slot}{weakref} = $target );
$weak_registry->{$slot}{stacktrace} = stacktrace(1);
$weak_registry->{$slot}{renumber} = 1 unless $_[2];
}
weaken( $reg_of_regs{ refaddr($weak_registry) } = $weak_registry )
unless( $reg_of_regs{ refaddr($weak_registry) } );
$target;
}
# Renumber everything we auto-named on a thread spawn
sub CLONE {
my @individual_regs = grep { scalar keys %{$_||{}} } values %reg_of_regs;
%reg_of_regs = ();
for my $reg (@individual_regs) {
my @live_slots = grep { defined $reg->{$_}{weakref} } keys %$reg
or next;
my @live_instances = @{$reg}{@live_slots};
$reg = {}; # get a fresh hashref in the new thread ctx
weaken( $reg_of_regs{refaddr($reg)} = $reg );
while (@live_slots) {
my $slot = shift @live_slots;
my $inst = shift @live_instances;
$slot =~ s/0x[0-9A-F]+/'0x' . sprintf ('0x%x', refaddr($inst))/ieg
if $inst->{renumber};
$reg->{$slot} = $inst;
}
}
}
sub assert_empty_weakregistry {
my ($weak_registry, $quiet) = @_;
croak 'Expecting a registry hashref' unless ref $weak_registry eq 'HASH';
return unless keys %$weak_registry;
my $tb = eval { Test::Builder->new }
or croak 'Calling test_weakregistry without a loaded Test::Builder makes no sense';
for my $slot (sort keys %$weak_registry) {
next if ! defined $weak_registry->{$slot}{weakref};
$tb->BAILOUT("!!!! WEAK REGISTRY SLOT $slot IS NOT A WEAKREF !!!!")
unless isweak( $weak_registry->{$slot}{weakref} );
}
for my $slot (sort keys %$weak_registry) {
! defined $weak_registry->{$slot}{weakref} and next if $quiet;
$tb->ok (! defined $weak_registry->{$slot}{weakref}, "No leaks of $slot") or do {
$leaks_found = 1;
my $diag = '';
$diag .= Devel::FindRef::track ($weak_registry->{$slot}{weakref}, 20) . "\n"
if ( $ENV{TEST_VERBOSE} && eval { require Devel::FindRef });
if (my $stack = $weak_registry->{$slot}{stacktrace}) {
$diag .= " Reference first seen$stack";
}
$tb->diag($diag) if $diag;
};
}
}
END {
if ($INC{'Test/Builder.pm'}) {
my $tb = Test::Builder->new;
# we check for test passage - a leak may be a part of a TODO
if ($leaks_found and !$tb->is_passing) {
$tb->diag(sprintf
"\n\n%s\n%s\n\nInstall Devel::FindRef and re-run the test with set "
. '$ENV{TEST_VERBOSE} (prove -v) to see a more detailed leak-report'
. "\n\n%s\n%s\n\n", ('#' x 16) x 4
) if ( !$ENV{TEST_VERBOSE} or !$INC{'Devel/FindRef.pm'} );
}
else {
$tb->note("Auto checked $refs_traced references for leaks - none detected");
}
}
}
1;