File: Overload.t

package info (click to toggle)
libtype-tiny-perl 2.002001-1
  • links: PTS, VCS
  • area: main
  • in suites: bookworm
  • size: 3,948 kB
  • sloc: perl: 14,610; makefile: 2; sh: 1
file content (162 lines) | stat: -rw-r--r-- 6,513 bytes parent folder | download
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
=pod

=encoding utf-8

=head1 PURPOSE

Basic tests for B<Overload> from L<Types::Standard>.

=head1 AUTHOR

Toby Inkster E<lt>tobyink@cpan.orgE<gt>.

=head1 COPYRIGHT AND LICENCE

This software is copyright (c) 2019-2023 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 warnings;
use Test::More;
use Test::Fatal;
use Test::TypeTiny;
use Types::Standard qw( Overload );

isa_ok(Overload, 'Type::Tiny', 'Overload');
is(Overload->name, 'Overload', 'Overload has correct name');
is(Overload->display_name, 'Overload', 'Overload has correct display_name');
is(Overload->library, 'Types::Standard', 'Overload knows it is in the Types::Standard library');
ok(Types::Standard->has_type('Overload'), 'Types::Standard knows it has type Overload');
ok(!Overload->deprecated, 'Overload is not deprecated');
ok(!Overload->is_anon, 'Overload is not anonymous');
ok(Overload->can_be_inlined, 'Overload can be inlined');
is(exception { Overload->inline_check(q/$xyz/) }, undef, "Inlining Overload doesn't throw an exception");
ok(!Overload->has_coercion, "Overload doesn't have a coercion");
ok(Overload->is_parameterizable, "Overload is parameterizable");
is(Overload->type_default, undef, "Overload 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 },
	fail => '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],
	fail => 'blessed arrayref'         => bless([], 'SomePkg'),
	fail => 'empty hashref'            => {},
	fail => 'hashref'                  => { foo => 1 },
	fail => 'blessed hashref'          => bless({}, 'SomePkg'),
	fail => 'coderef'                  => sub { 1 },
	fail => 'blessed coderef'          => bless(sub { 1 }, 'SomePkg'),
	fail => 'glob'                     => do { no warnings 'once'; *SOMETHING },
	fail => 'globref'                  => do { no warnings 'once'; my $x = *SOMETHING; \$x },
	fail => 'blessed globref'          => bless(do { no warnings 'once'; my $x = *SOMETHING; \$x }, 'SomePkg'),
	fail => 'regexp'                   => qr/./,
	fail => 'blessed regexp'           => bless(qr/./, 'SomePkg'),
	fail => 'filehandle'               => do { open my $x, '<', $0 or die; $x },
	fail => '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 }] },
#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($value, Overload, ucfirst("$label should pass Overload"));
	}
	elsif ($expect eq 'fail') {
		should_fail($value, Overload, ucfirst("$label should fail Overload"));
	}
	else {
		fail("expected '$expect'?!");
	}
}

#
# Type::Tiny itself overloads q[&{}] and q[""] but not q[${}].
#

should_pass(Overload, Overload[ q[&{}] ]);
should_pass(Overload, Overload[ q[""] ]);
should_fail(Overload, Overload[ q[${}] ]);

#
# It's possible to check multiple overloaded operations.
#

should_pass(Overload, Overload[ q[&{}], q[""] ]);
should_fail(Overload, Overload[ q[""], q[${}] ]);
should_fail(Overload, Overload[ q[&{}], q[${}] ]);

#
# In the following example, $fortytwo_withfallback doesn't overload
# '+' but still passes Overload['+'] because it provides a numification
# overload and allows fallbacks.
#

my $fortytwo_nofallback = do {
	package Local::OL::NoFallback;
	use overload q[0+] => sub { ${$_[0]} };
	my $x = 42;
	bless \$x;
};

my $fortytwo_withfallback = do {
	package Local::OL::WithFallback;
	use overload q[0+] => sub { ${$_[0]} }, fallback => 1;
	my $x = 42;
	bless \$x;
};

should_pass($fortytwo_nofallback, Overload['0+']);
should_pass($fortytwo_withfallback, Overload['0+']);
should_fail($fortytwo_nofallback, Overload['+']);
should_fail($fortytwo_withfallback, Overload['+']);

done_testing;