Storable/t/recurse.t

#!./perl
#
#  Copyright (c) 1995-2000, Raphael Manfredi
#
#  You may redistribute only under the same terms as Perl 5, as specified
#  in the README file that comes with the distribution.
#
use Config;

sub BEGIN {
    unshift @INC, 't';
    unshift @INC, 't/compat' if $] < 5.006002;
    if ($ENV{PERL_CORE} and $Config{'extensions'} !~ /\bStorable\b/) {
        print "1..0 # Skip: Storable was not built\n";
        exit 0;
    }
}

use Storable qw(freeze thaw dclone);

$Storable::flags = Storable::FLAGS_COMPAT;

use Test::More tests => 39;

package OBJ_REAL;

use Storable qw(freeze thaw);

@x = ('a', 1);

sub make { bless [], shift }

sub STORABLE_freeze {
    my $self = shift;
    my $cloning = shift;
    die "STORABLE_freeze" unless Storable::is_storing;
    return (freeze(\@x), $self);
}

sub STORABLE_thaw {
    my $self = shift;
    my $cloning = shift;
    my ($x, $obj) = @_;
    die "STORABLE_thaw #1" unless $obj eq $self;
    my $len = length $x;
    my $a = thaw $x;
    die "STORABLE_thaw #2" unless ref $a eq 'ARRAY';
    die "STORABLE_thaw #3" unless @$a == 2 && $a->[0] eq 'a' && $a->[1] == 1;
    @$self = @$a;
    die "STORABLE_thaw #4" unless Storable::is_retrieving;
}

package OBJ_SYNC;

@x = ('a', 1);

sub make { bless {}, shift }

sub STORABLE_freeze {
    my $self = shift;
    my ($cloning) = @_;
    return if $cloning;
    return ("", \@x, $self);
}

sub STORABLE_thaw {
    my $self = shift;
    my ($cloning, $undef, $a, $obj) = @_;
    die "STORABLE_thaw #1" unless $obj eq $self;
    die "STORABLE_thaw #2" unless ref $a eq 'ARRAY' || @$a != 2;
    $self->{ok} = $self;
}

package OBJ_SYNC2;

use Storable qw(dclone);

sub make {
    my $self = bless {}, shift;
    my ($ext) = @_;
    $self->{sync} = OBJ_SYNC->make;
    $self->{ext} = $ext;
    return $self;
}

sub STORABLE_freeze {
    my $self = shift;
    my %copy = %$self;
    my $r = \%copy;
    my $t = dclone($r->{sync});
    return ("", [$t, $self->{ext}], $r, $self, $r->{ext});
}

sub STORABLE_thaw {
    my $self = shift;
    my ($cloning, $undef, $a, $r, $obj, $ext) = @_;
    die "STORABLE_thaw #1" unless $obj eq $self;
    die "STORABLE_thaw #2" unless ref $a eq 'ARRAY';
    die "STORABLE_thaw #3" unless ref $r eq 'HASH';
    die "STORABLE_thaw #4" unless $a->[1] == $r->{ext};
    $self->{ok} = $self;
    ($self->{sync}, $self->{ext}) = @$a;
}

package OBJ_REAL2;

use Storable qw(freeze thaw);

$MAX = 20;
$recursed = 0;
$hook_called = 0;

sub make { bless [], shift }

sub STORABLE_freeze {
    my $self = shift;
    $hook_called++;
    return (freeze($self), $self) if ++$recursed < $MAX;
    return ("no", $self);
}

sub STORABLE_thaw {
    my $self = shift;
    my $cloning = shift;
    my ($x, $obj) = @_;
    die "STORABLE_thaw #1" unless $obj eq $self;
    $self->[0] = thaw($x) if $x ne "no";
    $recursed--;
}

package main;

my $real = OBJ_REAL->make;
my $x = freeze $real;
isnt($x, undef);

my $y = thaw $x;
is(ref $y, 'OBJ_REAL');
is($y->[0], 'a');
is($y->[1], 1);

my $sync = OBJ_SYNC->make;
$x = freeze $sync;
isnt($x, undef);

$y = thaw $x;
is(ref $y, 'OBJ_SYNC');
is($y->{ok}, $y);

my $ext = [1, 2];
$sync = OBJ_SYNC2->make($ext);
$x = freeze [$sync, $ext];
isnt($x, undef);

my $z = thaw $x;
$y = $z->[0];
is(ref $y, 'OBJ_SYNC2');
is($y->{ok}, $y);
is(ref $y->{sync}, 'OBJ_SYNC');
is($y->{ext}, $z->[1]);

$real = OBJ_REAL2->make;
$x = freeze $real;
isnt($x, undef);
is($OBJ_REAL2::recursed, $OBJ_REAL2::MAX);
is($OBJ_REAL2::hook_called, $OBJ_REAL2::MAX);

$y = thaw $x;
is(ref $y, 'OBJ_REAL2');
is($OBJ_REAL2::recursed, 0);

$x = dclone $real;
isnt($x, undef);
is(ref $x, 'OBJ_REAL2');
is($OBJ_REAL2::recursed, 0);
is($OBJ_REAL2::hook_called, 2 * $OBJ_REAL2::MAX);

is(Storable::is_storing, '');
is(Storable::is_retrieving, '');

#
# The following was a test-case that Salvador Ortiz Garcia <sog@msg.com.mx>
# sent me, along with a proposed fix.
#

package Foo;

sub new {
    my $class = shift;
    my $dat = shift;
    return bless {dat => $dat}, $class;
}

package Bar;
sub new {
    my $class = shift;
    return bless {
        a => 'dummy',
        b => [
            Foo->new(1),
            Foo->new(2), # Second instance of a Foo
          ]
    }, $class;
}

sub STORABLE_freeze {
    my($self,$clonning) = @_;
    return "$self->{a}", $self->{b};
}

sub STORABLE_thaw {
    my($self,$clonning,$dummy,$o) = @_;
    $self->{a} = $dummy;
    $self->{b} = $o;
}

package main;

my $bar = new Bar;
my $bar2 = thaw freeze $bar;

is(ref($bar2), 'Bar');
is(ref($bar->{b}[0]), 'Foo');
is(ref($bar->{b}[1]), 'Foo');
is(ref($bar2->{b}[0]), 'Foo');
is(ref($bar2->{b}[1]), 'Foo');

#
# The following attempts to make sure blessed objects are blessed ASAP
# at retrieve time.
#

package CLASS_1;

sub make {
    my $self = bless {}, shift;
    return $self;
}

package CLASS_2;

sub make {
    my $self = bless {}, shift;
    my ($o) = @_;
    $self->{c1} = CLASS_1->make();
    $self->{o} = $o;
    $self->{c3} = bless CLASS_1->make(), "CLASS_3";
    $o->set_c2($self);
    return $self;
}

sub STORABLE_freeze {
    my($self, $clonning) = @_;
    return "", $self->{c1}, $self->{c3}, $self->{o};
}

sub STORABLE_thaw {
    my($self, $clonning, $frozen, $c1, $c3, $o) = @_;
    main::is(ref $self, "CLASS_2");
    main::is(ref $c1, "CLASS_1");
    main::is(ref $c3, "CLASS_3");
    main::is(ref $o, "CLASS_OTHER");
    $self->{c1} = $c1;
    $self->{c3} = $c3;
}

package CLASS_OTHER;

sub make {
    my $self = bless {}, shift;
    return $self;
}

sub set_c2 { $_[0]->{c2} = $_[1] }

#
# Is the reference count of the extra references returned from a
# STORABLE_freeze hook correct? [ID 20020601.005 (#9436)]
#
package Foo2;

sub new {
    my $self = bless {}, $_[0];
    $self->{freezed} = "$self";
    return $self;
}

sub DESTROY {
    my $self = shift;
    $::refcount_ok = 1 unless "$self" eq $self->{freezed};
}

package Foo3;

sub new {
    bless {}, $_[0];
}

sub STORABLE_freeze {
    my $obj = shift;
    return ("", $obj, Foo2->new);
}

sub STORABLE_thaw { } # Not really used

package main;

my $o = CLASS_OTHER->make();
my $c2 = CLASS_2->make($o);
my $so = thaw freeze $o;

our $refcount_ok = 0;
thaw freeze(Foo3->new);
is($refcount_ok, 1, "check refcount");

# Check stack overflows [cpan #97526]
# JSON::XS limits this to 512.
# Small 64bit systems fail with 1200 (c++ debugging), with gcc 3000.
# Optimized 64bit allows up to 33.000 recursion depth.
# with asan the limit is 255 though.

local $Storable::recursion_limit = 30;
local $Storable::recursion_limit_hash = 20;
sub MAX_DEPTH () { Storable::stack_depth() }
sub MAX_DEPTH_HASH () { Storable::stack_depth_hash() }
{
    my $t;
    print "# max depth ", MAX_DEPTH, "\n";
    $t = [$t] for 1 .. MAX_DEPTH;
    dclone $t;
    pass "can nest ".MAX_DEPTH." array refs";
}
{
    my $t;
    $t = {1=>$t} for 1 .. MAX_DEPTH_HASH-10;
    dclone $t;
    pass "can nest ".(MAX_DEPTH_HASH)." hash refs";
}
{
    my (@t);
    push @t, [{}] for 1..5000;
    #diag 'trying simple array[5000] stack overflow, no recursion';
    dclone \@t;
    is $@, '', 'No simple array[5000] stack overflow #257';
}

eval {
    my $t;
    $t = [$t] for 1 .. MAX_DEPTH*2;
    eval { note('trying catching recursive aref stack overflow') };
    dclone $t;
};
like $@, qr/Max\. recursion depth with nested structures exceeded/,
      'Caught aref stack overflow '.MAX_DEPTH*2;

if ($ENV{APPVEYOR} and length(pack "p", "") >= 8) {
    # TODO: need to repro this fail on a small machine.
    ok(1, "skip dclone of big hash");
}
else {
    eval {
        my $t;
        # 35.000 will cause appveyor 64bit windows to fail earlier
        $t = {1=>$t} for 1 .. MAX_DEPTH * 2;
        eval { note('trying catching recursive href stack overflow') };
        dclone $t;
    };
    like $@, qr/Max\. recursion depth with nested structures exceeded/,
      'Caught href stack overflow '.MAX_DEPTH_HASH*2;
}

{
    # perl #133326
    my @tt;
    #$Storable::DEBUGME=1;
    for (1..16000) {
        my $t = [[[]]];
        push @tt, $t;
    }
    ok(eval { dclone \@tt; 1 },
       "low depth structure shouldn't be treated as nested");
}