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#!/usr/bin/perl -w
my ($Has_PH, $Field);
BEGIN {
$Has_PH = $] < 5.009;
$Field = $Has_PH ? "pseudo-hash field" : "class field";
}
my $W;
BEGIN {
$W = 0;
$SIG{__WARN__} = sub {
if ($_[0] =~ /^Hides field '.*?' in base class/) {
$W++;
}
else {
warn $_[0];
}
};
}
use strict;
use Test::More tests => 29;
BEGIN { use_ok('base'); }
package B1;
use fields qw(b1 b2 b3);
package B2;
use fields '_b1';
use fields qw(b1 _b2 b2);
sub new { fields::new(shift) }
package B3;
use fields qw(b4 _b5 b6 _b7);
package D1;
use base 'B1';
use fields qw(d1 d2 d3);
package D2;
use base 'B1';
use fields qw(_d1 _d2);
use fields qw(d1 d2);
package D3;
use base 'B2';
use fields qw(b1 d1 _b1 _d1); # hide b1
package D4;
use base 'D3';
use fields qw(_d3 d3);
package M;
sub m {}
package D5;
use base qw(M B2);
# Test that multiple inheritance fails.
package D6;
eval { 'base'->import(qw(B2 M B3)); };
::like($@, qr/can't multiply inherit fields/i,
'No multiple field inheritance');
package Foo::Bar;
use base 'B1';
package Foo::Bar::Baz;
use base 'Foo::Bar';
use fields qw(foo bar baz);
# Test repeatability for when modules get reloaded.
package B1;
use fields qw(b1 b2 b3);
package D3;
use base 'B2';
use fields qw(b1 d1 _b1 _d1); # hide b1
# Test that a package with only private fields gets inherited properly
package B7;
use fields qw(_b1);
package D7;
use base qw(B7);
use fields qw(b1);
# Test that an intermediate package with no fields doesn't cause a problem.
package B8;
use fields qw(_b1);
package D8;
use base qw(B8);
package D8A;
use base qw(D8);
use fields qw(b1);
package main;
my %EXPECT = (
B1 => [qw(b1 b2 b3)],
D1 => [qw(b1 b2 b3 d1 d2 d3)],
D2 => [qw(b1 b2 b3 _d1 _d2 d1 d2)],
M => [qw()],
B2 => [qw(_b1 b1 _b2 b2)],
D3 => [(undef,undef,undef,
qw(b2 b1 d1 _b1 _d1))], # b1 is hidden
D4 => [(undef,undef,undef,
qw(b2 b1 d1),undef,undef,qw(_d3 d3))],
D5 => [undef, 'b1', undef, 'b2'],
B3 => [qw(b4 _b5 b6 _b7)],
B7 => [qw(_b1)],
D7 => [undef, 'b1'],
B8 => [qw(_b1)],
D8 => [undef],
D8A => [undef, 'b1'],
'Foo::Bar' => [qw(b1 b2 b3)],
'Foo::Bar::Baz' => [qw(b1 b2 b3 foo bar baz)],
);
while(my($class, $efields) = each %EXPECT) {
no strict 'refs';
my %fields = %{$class.'::FIELDS'};
my %expected_fields;
foreach my $idx (1..@$efields) {
my $key = $efields->[$idx-1];
next unless $key;
$expected_fields{$key} = $idx;
}
::is_deeply(\%fields, \%expected_fields, "%FIELDS check: $class");
}
# Did we get the appropriate amount of warnings?
is( $W, 1, 'right warnings' );
# A simple object creation and attribute access test
my B2 $obj1 = D3->new;
$obj1->{b1} = "B2";
my D3 $obj2 = $obj1;
$obj2->{b1} = "D3";
# We should get compile time failures field name typos
eval q(return; my D3 $obj3 = $obj2; $obj3->{notthere} = "");
like $@,
qr/^No such $Field "notthere" in variable \$obj3 of type D3/,
"Compile failure of undeclared fields (helem)";
SKIP: {
# Slices
# We should get compile time failures field name typos
skip "Doesn't work before 5.9", 2 if $] < 5.009;
eval q(return; my D3 $obj3 = $obj2; my $k; @$obj3{$k,'notthere'} = ());
like $@,
qr/^No such $Field "notthere" in variable \$obj3 of type D3/,
"Compile failure of undeclared fields (hslice)";
eval q(return; my D3 $obj3 = $obj2; my $k; @{$obj3}{$k,'notthere'} = ());
like
$@, qr/^No such $Field "notthere" in variable \$obj3 of type D3/,
"Compile failure of undeclared fields (hslice (block form))";
}
@$obj1{"_b1", "b1"} = (17, 29);
is( $obj1->{_b1}, 17 );
is( $obj1->{b1}, 29 );
@$obj1{'_b1', 'b1'} = (44,28);
is( $obj1->{_b1}, 44 );
is( $obj1->{b1}, 28 );
# Break multiple inheritance with a field name clash.
package E1;
use fields qw(yo this _lah meep 42);
package E2;
use fields qw(_yo ahhh this);
eval {
package Broken;
# The error must occur at run time for the eval to catch it.
require base;
'base'->import(qw(E1 E2));
};
::like( $@, qr/Can't multiply inherit fields/i, 'Again, no multi inherit' );
# Test that a package with no fields can inherit from a package with
# fields, and that pseudohash messages don't show up
package B9;
use fields qw(b1);
sub _mk_obj { fields::new($_[0])->{'b1'} };
package D9;
use base qw(B9);
package main;
{
my $w = 0;
local $SIG{__WARN__} = sub { $w++ };
B9->_mk_obj();
# used tp emit a warning that pseudohashes are deprecated, because
# %FIELDS wasn't blessed.
D9->_mk_obj();
is ($w, 0, "pseudohash warnings in derived class with no fields of it's own");
}
# [perl #31078] an intermediate class with no additional fields caused
# hidden fields in base class to get stomped on
{
package X;
use fields qw(X1 _X2);
sub new {
my X $self = shift;
$self = fields::new($self) unless ref $self;
$self->{X1} = "x1";
# FIXME. This code is dead on blead because the test is skipped.
# The test states that it's being skipped because restricted hashes
# don't support a feature. Presumably we need to make that feature
# supported. Bah.
# use Devel::Peek; Dump($self);
$self->{_X2} = "_x2";
return $self;
}
sub get_X2 { my X $self = shift; $self->{_X2} }
package Y;
use base qw(X);
sub new {
my Y $self = shift;
$self = fields::new($self) unless ref $self;
$self->SUPER::new();
return $self;
}
package Z;
use base qw(Y);
use fields qw(Z1);
sub new {
my Z $self = shift;
$self = fields::new($self) unless ref $self;
$self->SUPER::new();
$self->{Z1} = 'z1';
return $self;
}
package main;
if ($Has_PH) {
my Z $c = Z->new();
is($c->get_X2, '_x2', "empty intermediate class");
}
else {
SKIP: {
skip "restricted hashes don't support private fields properly", 1;
}
}
}