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|
use strict;
$^W++;
use Class::Prototyped qw(:EZACCESS);
use Data::Dumper;
use Test;
BEGIN {
$|++;
plan tests => 12
}
$Data::Dumper::Sortkeys = 1;
$Data::Dumper::Sortkeys = 1;
my $record = '';
package MyClass;
@MyClass::ISA = qw(Class::Prototyped);
sub DESTROY {
$record .= "You are in MyClass::DESTROY for " . ref($_[0]) . "\n";
}
package MyClass_Alt;
@MyClass_Alt::ISA = qw(Class::Prototyped);
sub DESTROY {
$record .= "You are in MyClass_Alt::DESTROY for " . ref($_[0]) . "\n";
}
package main;
my $name1;
my $name2;
my $name3;
# This demonstrates normal destruction.
{
my $foo = MyClass->new(
'destroy!' => sub {
$record .= "You are in the objects destroy.\n";
$_[0]->super('destroy');
$record .= "Just called super-destroy.\n";
},
);
$name1 = ref($foo);
}
ok( $record, <<END);
You are in the objects destroy.
Just called super-destroy.
You are in MyClass::DESTROY for $name1
END
use Data::Dumper;
# This demonstrates destruction where $p2 has a reference in it to $p1. Note
# that the destructor for $p1 runs as soon as the C::P::destory destructor
# runs on $p2, thus interrupting the $p2 destruction sequence
$record = '';
{
my $p2 = MyClass->new(
'destroy!' => sub {
$record .= "p2 before super for " . ref($_[0]) . "\n";
$_[0]->super('destroy');
$record .= "p2 after super for " . ref($_[0]) . "\n";
},
);
$name2 = ref($p2);
{
my $p1 = MyClass->new(
'destroy!' => sub {
$record .= "p1 before super for " . ref($_[0]) . "\n";
$_[0]->super('destroy');
$record .= "p1 after super for " . ref($_[0]) . "\n";
},
);
$name1 = ref($p1);
$p2->addSlot('p1' => $p1);
}
}
ok( $record, <<END);
p2 before super for $name2
p1 before super for $name1
p1 after super for $name1
You are in MyClass::DESTROY for $name1
p2 after super for $name2
You are in MyClass::DESTROY for $name2
END
# This demonstrates destruction where $p2 has a parent slot that points to
# $p1. In this situation, the $p2 destruction sequence is not interrupted
# because the reference to $p1 is not removed until the $p2 destruction
# sequence has completed.
$record = '';
{
my $p2 = MyClass->new(
'destroy!' => sub {
$record .= "p2 before super for " . ref($_[0]) . "\n";
$_[0]->super('destroy');
$record .= "p2 after super for " . ref($_[0]) . "\n";
},
);
$name2 = ref($p2);
{
my $p1 = MyClass->new(
'destroy!' => sub {
$record .= "p1 before super for " . ref($_[0]) . "\n";
$_[0]->super('destroy');
$record .= "p1 after super for " . ref($_[0]) . "\n";
},
);
$name1 = ref($p1);
$p2->addSlot('parent*' => $p1);
}
}
ok( $record, <<END);
p2 before super for $name2
p2 after super for $name2
You are in MyClass::DESTROY for $name2
p1 before super for $name1
p1 after super for $name1
You are in MyClass::DESTROY for $name1
END
# In this test, $p3 and $p2 reference $p1. The destructor for $p2 completes
# removing one of the references to $p1. Then the destructor for $p3 runs,
# at which point the last reference to $p1 is removed and so the destructor
# for $p1 interrupts the $p3 destruction sequence.
$record = '';
{
my $p3 = MyClass->new(
'destroy!' => sub {
$record .= "p3 before super for " . ref($_[0]) . "\n";
$_[0]->super('destroy');
$record .= "p3 after super for " . ref($_[0]) . "\n";
},
);
$name3 = ref($p3);
{
my $p2 = MyClass->new(
'destroy!' => sub {
$record .= "p2 before super for " . ref($_[0]) . "\n";
$_[0]->super('destroy');
$record .= "p2 after super for " . ref($_[0]) . "\n";
},
);
$name2 = ref($p2);
{
my $p1 = MyClass->new(
'destroy!' => sub {
$record .= "p1 before super for " . ref($_[0]) . "\n";
$_[0]->super('destroy');
$record .= "p1 after super for " . ref($_[0]) . "\n";
},
);
$name1 = ref($p1);
$p2->addSlot('p1' => $p1);
$p3->addSlot('p1' => $p1);
}
}
}
ok( $record, <<END);
p2 before super for $name2
p2 after super for $name2
You are in MyClass::DESTROY for $name2
p3 before super for $name3
p1 before super for $name1
p1 after super for $name1
You are in MyClass::DESTROY for $name1
p3 after super for $name3
You are in MyClass::DESTROY for $name3
END
# Same test, but using parent slots instead. Note that as a result, the
# destruction sequence for $p3 completes before the destructor for $p1
# is triggered
$record = '';
{
my $p3 = MyClass->new(
'destroy!' => sub {
$record .= "p3 before super for " . ref($_[0]) . "\n";
$_[0]->super('destroy');
$record .= "p3 after super for " . ref($_[0]) . "\n";
},
);
$name3 = ref($p3);
{
my $p2 = MyClass->new(
'destroy!' => sub {
$record .= "p2 before super for " . ref($_[0]) . "\n";
$_[0]->super('destroy');
$record .= "p2 after super for " . ref($_[0]) . "\n";
},
);
$name2 = ref($p2);
{
my $p1 = MyClass->new(
'destroy!' => sub {
$record .= "p1 before super for " . ref($_[0]) . "\n";
$_[0]->super('destroy');
$record .= "p1 after super for " . ref($_[0]) . "\n";
},
);
$name1 = ref($p1);
$p2->addSlot('parent*' => $p1);
$p3->addSlot('parent*' => $p1);
}
}
}
ok( $record, <<END);
p2 before super for $name2
p2 after super for $name2
You are in MyClass::DESTROY for $name2
p3 before super for $name3
p3 after super for $name3
You are in MyClass::DESTROY for $name3
p1 before super for $name1
p1 after super for $name1
You are in MyClass::DESTROY for $name1
END
# Here we use qw([parent* promote]) instead of parent* to move the parent slot
# up in precedence over class*. In the previous tests, the destroy method
# wasn't inherited from $p1 because the destroy method in C::P by way of
# MyClass took precedence.
$record = '';
{
my $p2 = MyClass->new(
'destroy!' => sub {
$record .= "p2 before super for " . ref($_[0]) . "\n";
$_[0]->super('destroy');
$record .= "p2 after super for " . ref($_[0]) . "\n";
},
);
$name2 = ref($p2);
{
my $p1 = MyClass->new(
'destroy!' => sub {
$record .= "p1 before super for " . ref($_[0]) . "\n";
$_[0]->super('destroy');
$record .= "p1 after super for " . ref($_[0]) . "\n";
},
);
$name1 = ref($p1);
$p2->addSlot([qw(parent* promote)] => $p1);
}
}
ok( $record, <<END);
p2 before super for $name2
p1 before super for $name2
p1 after super for $name2
p2 after super for $name2
You are in MyClass::DESTROY for $name2
p1 before super for $name1
p1 after super for $name1
You are in MyClass::DESTROY for $name1
END
# Note that we get the same behavior (including access to MyClass::DESTROY
# via the $p1 inheritance path) when we have a classless object.
$record = '';
{
my $p2 = Class::Prototyped->new(
'destroy!' => sub {
$record .= "p2 before super for " . ref($_[0]) . "\n";
$_[0]->super('destroy');
$record .= "p2 after super for " . ref($_[0]) . "\n";
},
);
$name2 = ref($p2);
{
my $p1 = MyClass->new(
'destroy!' => sub {
$record .= "p1 before super for " . ref($_[0]) . "\n";
$_[0]->super('destroy');
$record .= "p1 after super for " . ref($_[0]) . "\n";
},
);
$name1 = ref($p1);
$p2->addSlot('parent*' => $p1);
}
}
ok( $record, <<END);
p2 before super for $name2
p1 before super for $name2
p1 after super for $name2
p2 after super for $name2
You are in MyClass::DESTROY for $name2
p1 before super for $name1
p1 after super for $name1
You are in MyClass::DESTROY for $name1
END
# Demonstration of two objects referencing the same chained destructor
$record = '';
{
my $p3 = MyClass->new(
'destroy!' => sub {
$record .= "p3 before super for " . ref($_[0]) . "\n";
$_[0]->super('destroy');
$record .= "p3 after super for " . ref($_[0]) . "\n";
},
);
$name3 = ref($p3);
{
my $p2 = MyClass->new(
'destroy!' => sub {
$record .= "p2 before super for " . ref($_[0]) . "\n";
$_[0]->super('destroy');
$record .= "p2 after super for " . ref($_[0]) . "\n";
},
);
$name2 = ref($p2);
{
my $p1 = MyClass->new(
'destroy!' => sub {
$record .= "p1 before super for " . ref($_[0]) . "\n";
$_[0]->super('destroy');
$record .= "p1 after super for " . ref($_[0]) . "\n";
},
);
$name1 = ref($p1);
$p2->addSlot([qw(parent* promote)] => $p1);
$p3->addSlot([qw(parent* promote)] => $p1);
}
}
}
ok( $record, <<END);
p2 before super for $name2
p1 before super for $name2
p1 after super for $name2
p2 after super for $name2
You are in MyClass::DESTROY for $name2
p3 before super for $name3
p1 before super for $name3
p1 after super for $name3
p3 after super for $name3
You are in MyClass::DESTROY for $name3
p1 before super for $name1
p1 after super for $name1
You are in MyClass::DESTROY for $name1
END
# Demonstration of chained destructors
$record = '';
{
my $p3 = MyClass->new(
'destroy!' => sub {
$record .= "p3 before super for " . ref($_[0]) . "\n";
$_[0]->super('destroy');
$record .= "p3 after super for " . ref($_[0]) . "\n";
},
);
$name3 = ref($p3);
{
my $p2 = MyClass->new(
'destroy!' => sub {
$record .= "p2 before super for " . ref($_[0]) . "\n";
$_[0]->super('destroy');
$record .= "p2 after super for " . ref($_[0]) . "\n";
},
);
$name2 = ref($p2);
$p3->addSlot([qw(parent* promote)] => $p2);
{
my $p1 = MyClass->new(
'destroy!' => sub {
$record .= "p1 before super for " . ref($_[0]) . "\n";
$_[0]->super('destroy');
$record .= "p1 after super for " . ref($_[0]) . "\n";
},
);
$name1 = ref($p1);
$p2->addSlot([qw(parent* promote)] => $p1);
}
}
}
ok( $record, <<END);
p3 before super for $name3
p2 before super for $name3
p1 before super for $name3
p1 after super for $name3
p2 after super for $name3
p3 after super for $name3
You are in MyClass::DESTROY for $name3
p2 before super for $name2
p1 before super for $name2
p1 after super for $name2
p2 after super for $name2
You are in MyClass::DESTROY for $name2
p1 before super for $name1
p1 after super for $name1
You are in MyClass::DESTROY for $name1
END
# Demonstration of the search for DESTROY taking the same path as the search
# for destroy
$record = '';
{
my $p3 = MyClass->new(
'destroy!' => sub {
$record .= "p3 before super for " . ref($_[0]) . "\n";
$_[0]->super('destroy');
$record .= "p3 after super for " . ref($_[0]) . "\n";
},
);
$name3 = ref($p3);
{
my $p2 = MyClass->new(
'destroy!' => sub {
$record .= "p2 before super for " . ref($_[0]) . "\n";
$_[0]->super('destroy');
$record .= "p2 after super for " . ref($_[0]) . "\n";
},
);
$name2 = ref($p2);
$p3->addSlot('parent2**' => $p2);
{
my $p1 = MyClass_Alt->new(
'destroy!' => sub {
$record .= "p1 before super for " . ref($_[0]) . "\n";
$_[0]->super('destroy');
$record .= "p1 after super for " . ref($_[0]) . "\n";
},
);
$name1 = ref($p1);
$p3->addSlot('parent1**' => $p1);
}
}
}
ok( $record, <<END);
p3 before super for $name3
p1 before super for $name3
p1 after super for $name3
p3 after super for $name3
You are in MyClass_Alt::DESTROY for $name3
p1 before super for $name1
p1 after super for $name1
You are in MyClass_Alt::DESTROY for $name1
p2 before super for $name2
p2 after super for $name2
You are in MyClass::DESTROY for $name2
END
# Demonstration of the search for DESTROY taking a different path from the
# search for destroy
$record = '';
{
my $p3 = MyClass->new(
'destroy!' => sub {
$record .= "p3 before super for " . ref($_[0]) . "\n";
$_[0]->super('destroy');
$record .= "p3 after super for " . ref($_[0]) . "\n";
},
);
$name3 = ref($p3);
{
my $p2 = MyClass->new(
'destroy!' => sub {
$record .= "p2 before super for " . ref($_[0]) . "\n";
$_[0]->super('destroy');
$record .= "p2 after super for " . ref($_[0]) . "\n";
},
);
$name2 = ref($p2);
$p3->addSlot('parent2**' => $p2);
{
my $p1 = Class::Prototyped->new(
'destroy!' => sub {
$record .= "p1 before super for " . ref($_[0]) . "\n";
$_[0]->super('destroy');
$record .= "p1 after super for " . ref($_[0]) . "\n";
},
);
$name1 = ref($p1);
$p3->addSlot('parent1**' => $p1);
}
}
}
ok( $record, <<END);
p3 before super for $name3
p1 before super for $name3
p1 after super for $name3
p3 after super for $name3
You are in MyClass::DESTROY for $name3
p1 before super for $name1
p1 after super for $name1
p2 before super for $name2
p2 after super for $name2
You are in MyClass::DESTROY for $name2
END
# Demonstration of a real-world dependency on the parent slot remaining viable
$record = '';
{
my $p3;
{
my $p2;
{
my $p1;
{
$p1 = Class::Prototyped->new(
name => 'p1',
count => 0,
);
my $ref = ref($p1);
$p1->addSlots(
'new!' => sub {
my $self = $_[0]->super('new', 'parent*' => @_);
$self->count($self->count()+1);
$record .= "Incremented count to " . $self->count . " using " .
ref($self) . " from new called on " . ref($_[0]) . "\n";
return $self;
},
'destroy!' => sub {
if (ref($_[0]) eq $ref) {
$record .= "p1::destroy called on self with a count of " .
$_[0]->count . "\n";
} else {
$record .= "p1::destroy called on " . $_[0]->name() . " (" .
ref($_[0]) . ")\n";
$_[0]->count($_[0]->count()-1);
$record .= "Decremented count to " . $_[0]->count . "\n";
}
},
);
}
$name1 = ref($p1);
$p2 = $p1->new(name => 'p2');
$name2 = ref($p2);
$p3 = $p2->new(name => 'p3');
$name3 = ref($p3);
}
}
}
ok( $record, <<END);
Incremented count to 1 using $name2 from new called on $name1
Incremented count to 2 using $name3 from new called on $name2
p1::destroy called on p3 ($name3)
Decremented count to 1
p1::destroy called on p2 ($name2)
Decremented count to 0
p1::destroy called on self with a count of 0
END
|
