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=pod
=encoding utf-8
=head1 PURPOSE
Basic tests for B<HasMethods> from L<Types::Standard>.
=head1 AUTHOR
Toby Inkster E<lt>tobyink@cpan.orgE<gt>.
=head1 COPYRIGHT AND LICENCE
This software is copyright (c) 2019-2025 by Toby Inkster.
This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.
=cut
use strict;
use Test::Requires qw(boolean);
use Types::Standard qw( HasMethods );
isa_ok(HasMethods, 'Type::Tiny', 'HasMethods');
is(HasMethods->name, 'HasMethods', 'HasMethods has correct name');
is(HasMethods->display_name, 'HasMethods', 'HasMethods has correct display_name');
is(HasMethods->library, 'Types::Standard', 'HasMethods knows it is in the Types::Standard library');
ok(Types::Standard->has_type('HasMethods'), 'Types::Standard knows it has type HasMethods');
ok(!HasMethods->deprecated, 'HasMethods is not deprecated');
ok(!HasMethods->is_anon, 'HasMethods is not anonymous');
ok(HasMethods->can_be_inlined, 'HasMethods can be inlined');
is(exception { HasMethods->inline_check(q/$xyz/) }, undef, "Inlining HasMethods doesn't throw an exception");
ok(!HasMethods->has_coercion, "HasMethods doesn't have a coercion");
ok(HasMethods->is_parameterizable, "HasMethods is parameterizable");
is(HasMethods->type_default, undef, "HasMethods has no type_default");
#
# The @tests array is a list of triples:
#
# 1. Expected result - pass, fail, or xxxx (undefined).
# 2. A description of the value being tested.
# 3. The value being tested.
#
my @tests = (
fail => 'undef' => undef,
fail => 'false' => !!0,
fail => 'true' => !!1,
fail => 'zero' => 0,
fail => 'one' => 1,
fail => 'negative one' => -1,
fail => 'non integer' => 3.1416,
fail => 'empty string' => '',
fail => 'whitespace' => ' ',
fail => 'line break' => "\n",
fail => 'random string' => 'abc123',
fail => 'loaded package name' => 'Type::Tiny',
fail => 'unloaded package name' => 'This::Has::Probably::Not::Been::Loaded',
fail => 'a reference to undef' => do { my $x = undef; \$x },
fail => 'a reference to false' => do { my $x = !!0; \$x },
fail => 'a reference to true' => do { my $x = !!1; \$x },
fail => 'a reference to zero' => do { my $x = 0; \$x },
fail => 'a reference to one' => do { my $x = 1; \$x },
fail => 'a reference to empty string' => do { my $x = ''; \$x },
fail => 'a reference to random string' => do { my $x = 'abc123'; \$x },
pass => 'blessed scalarref' => bless(do { my $x = undef; \$x }, 'SomePkg'),
fail => 'empty arrayref' => [],
fail => 'arrayref with one zero' => [0],
fail => 'arrayref of integers' => [1..10],
fail => 'arrayref of numbers' => [1..10, 3.1416],
pass => 'blessed arrayref' => bless([], 'SomePkg'),
fail => 'empty hashref' => {},
fail => 'hashref' => { foo => 1 },
pass => 'blessed hashref' => bless({}, 'SomePkg'),
fail => 'coderef' => sub { 1 },
pass => 'blessed coderef' => bless(sub { 1 }, 'SomePkg'),
fail => 'glob' => do { no warnings 'once'; *SOMETHING },
fail => 'globref' => do { no warnings 'once'; my $x = *SOMETHING; \$x },
pass => 'blessed globref' => bless(do { no warnings 'once'; my $x = *SOMETHING; \$x }, 'SomePkg'),
xxxx => 'regexp' => qr/./,
pass => 'blessed regexp' => bless(qr/./, 'SomePkg'),
fail => 'filehandle' => do { open my $x, '<', $0 or die; $x },
pass => 'filehandle object' => do { require IO::File; 'IO::File'->new($0, 'r') },
fail => 'ref to scalarref' => do { my $x = undef; my $y = \$x; \$y },
fail => 'ref to arrayref' => do { my $x = []; \$x },
fail => 'ref to hashref' => do { my $x = {}; \$x },
fail => 'ref to coderef' => do { my $x = sub { 1 }; \$x },
fail => 'ref to blessed hashref' => do { my $x = bless({}, 'SomePkg'); \$x },
pass => 'object stringifying to ""' => do { package Local::OL::StringEmpty; use overload q[""] => sub { "" }; bless [] },
pass => 'object stringifying to "1"' => do { package Local::OL::StringOne; use overload q[""] => sub { "1" }; bless [] },
pass => 'object numifying to 0' => do { package Local::OL::NumZero; use overload q[0+] => sub { 0 }; bless [] },
pass => 'object numifying to 1' => do { package Local::OL::NumOne; use overload q[0+] => sub { 1 }; bless [] },
pass => 'object overloading arrayref' => do { package Local::OL::Array; use overload q[@{}] => sub { $_[0]{array} }; bless {array=>[]} },
pass => 'object overloading hashref' => do { package Local::OL::Hash; use overload q[%{}] => sub { $_[0][0] }; bless [{}] },
pass => 'object overloading coderef' => do { package Local::OL::Code; use overload q[&{}] => sub { $_[0][0] }; bless [sub { 1 }] },
pass => 'object booling to false' => do { package Local::OL::BoolFalse; use overload q[bool] => sub { 0 }; bless [] },
pass => 'object booling to true' => do { package Local::OL::BoolTrue; use overload q[bool] => sub { 1 }; bless [] },
pass => 'boolean::false' => boolean::false,
pass => 'boolean::true' => boolean::true,
fail => 'builtin::false' => do { no warnings; builtin->can('false') ? builtin::false() : !!0 },
fail => 'builtin::true' => do { no warnings; builtin->can('true') ? builtin::true() : !!1 },
#TESTS
);
while (@tests) {
my ($expect, $label, $value) = splice(@tests, 0 , 3);
if ($expect eq 'xxxx') {
note("UNDEFINED OUTCOME: $label");
}
elsif ($expect eq 'pass') {
should_pass($value, HasMethods, ucfirst("$label should pass HasMethods"));
}
elsif ($expect eq 'fail') {
should_fail($value, HasMethods, ucfirst("$label should fail HasMethods"));
}
else {
fail("expected '$expect'?!");
}
}
use Scalar::Util qw( refaddr );
my $plain = HasMethods;
my $paramd = HasMethods[];
is(
refaddr($plain),
refaddr($paramd),
'parameterizing with [] has no effect'
);
my $p1 = HasMethods['foo'];
my $p2 = HasMethods['foo'];
is(refaddr($p1), refaddr($p2), 'parameterizing is cached');
#
# We need a real object to test HasMethods on.
# Luckily HasMethods IS an object!
#
should_pass(
HasMethods,
HasMethods['constraint'],
"Parameterized with one method name",
);
should_pass(
HasMethods,
HasMethods['constraint', 'name'],
"Parameterized with multiple method names",
);
should_fail(
HasMethods,
HasMethods['constraint', 'should_not_exist'],
"... acts as intersection (requires the object to support ALL the methods)"
);
{
# A package where $thing->foo works but
# $thing->can("foo") is false.
package Local::Liar1;
sub foo { 1 }
sub can {
return if $_[1] eq 'foo';
goto \&UNIVERSAL::can;
}
}
should_fail(
bless([], 'Local::Liar1'),
HasMethods['foo'],
"HasMethods should believe \$object->can() if it returns false."
);
{
# A package where $thing->foo breaks but
# $thing->can("foo") is true.
package Local::Liar2;
sub can {
return sub { 1 } if $_[1] eq 'foo';
goto \&UNIVERSAL::can;
}
}
should_pass(
bless([], 'Local::Liar2'),
HasMethods['foo'],
"HasMethods should believe \$object->can() if it returns true."
);
#
# HasMethods is for blessed objects only.
#
should_fail(
'Local::Liar2',
HasMethods['foo'],
"HasMethods does't work on class names, even if they can do a method."
);
done_testing;