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
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
|
package Perl::Critic::Policy::RegularExpressions::ProhibitEnumeratedClasses;
use 5.010001;
use strict;
use warnings;
use List::SomeUtils qw(all);
use Readonly;
use Perl::Critic::Utils qw( :severities );
use parent 'Perl::Critic::Policy';
our $VERSION = '1.156';
#-----------------------------------------------------------------------------
Readonly::Scalar my $DESC => q{Use named character classes};
Readonly::Scalar my $EXPL => [248];
Readonly::Array my @PATTERNS => ( # order matters: most to least specific
[q{ },'\\t','\\r','\\n'] => ['\\s', '\\S'],
['A-Z','a-z','0-9','_'] => ['\\w', '\\W'], # RT 69322
['A-Z','a-z'] => ['[[:alpha:]]','[[:^alpha:]]'],
['A-Z'] => ['[[:upper:]]','[[:^upper:]]'],
['a-z'] => ['[[:lower:]]','[[:^lower:]]'],
['0-9'] => ['\\d','\\D'],
['\w'] => [undef, '\\W'],
['\s'] => [undef, '\\S'],
);
#-----------------------------------------------------------------------------
sub supported_parameters { return qw() }
sub default_severity { return $SEVERITY_LOWEST }
sub default_themes { return qw( core pbp cosmetic unicode ) }
sub applies_to { return qw(PPI::Token::Regexp::Match
PPI::Token::Regexp::Substitute
PPI::Token::QuoteLike::Regexp) }
#-----------------------------------------------------------------------------
sub violates {
my ( $self, $elem, $document ) = @_;
# optimization: don't bother parsing the regexp if there are no character classes
return if $elem !~ m/\[/xms;
my $re = $document->ppix_regexp_from_element( $elem ) or return;
$re->failures() and return;
my $anyofs = $re->find( 'PPIx::Regexp::Structure::CharClass' )
or return;
foreach my $anyof ( @{ $anyofs } ) {
my $violation;
$violation = $self->_get_character_class_violations( $elem, $anyof )
and return $violation;
}
return; # OK
}
sub _get_character_class_violations {
my ($self, $elem, $anyof) = @_;
my %elements;
foreach my $element ( $anyof->children() ) {
$elements{ _fixup( $element ) } = 1;
}
for (my $i = 0; $i < @PATTERNS; $i += 2) { ##no critic (CStyleForLoop)
if (all { exists $elements{$_} } @{$PATTERNS[$i]}) {
my $neg = $anyof->negated();
my $improvement = $PATTERNS[$i + 1]->[$neg ? 1 : 0];
next if !defined $improvement;
if ($neg && ! defined $PATTERNS[$i + 1]->[0]) {
# the [^\w] => \W rule only applies if \w is the only token.
# that is it does not apply to [^\w\s]
next if 1 != scalar keys %elements;
}
my $orig = join q{}, '[', ($neg ? q{^} : ()), @{$PATTERNS[$i]}, ']';
return $self->violation( $DESC . " ($orig vs. $improvement)", $EXPL, $elem );
}
}
return; # OK
}
Readonly::Hash my %ORDINALS => (
ord "\n" => '\\n',
ord "\f" => '\\f',
ord "\r" => '\\r',
ord q< > => q< >,
);
sub _fixup {
my ( $element ) = @_;
if ( $element->isa( 'PPIx::Regexp::Token::Literal' ) ) {
my $ord = $element->ordinal();
exists $ORDINALS{$ord} and return $ORDINALS{$ord};
return $element->content();
} elsif ( $element->isa( 'PPIx::Regexp::Node' ) ) {
return join q{}, map{ _fixup( $_ ) } $element->elements();
} else {
return $element->content();
}
}
1;
__END__
#-----------------------------------------------------------------------------
=pod
=head1 NAME
Perl::Critic::Policy::RegularExpressions::ProhibitEnumeratedClasses - Use named character classes instead of explicit character lists.
=head1 AFFILIATION
This Policy is part of the core L<Perl::Critic|Perl::Critic>
distribution.
=head1 DESCRIPTION
This policy is not for everyone! If you are working in pure ASCII,
then disable it now or you may see some false violations.
On the other hand many of us are working in a multilingual world with
an extended character set, probably Unicode. In that world, patterns
like C<m/[A-Z]/> can be a source of bugs when you really meant
C<m/\p{IsUpper}/>. This policy catches a selection of possible
incorrect character class usage.
Specifically, the patterns are:
B<C<[\t\r\n\f\ ]>> vs. B<C<\s>>
B<C<[\t\r\n\ ]>> vs. B<C<\s>> (because many people forget C<\f>)
B<C<[A-Za-z0-9_]>> vs. B<C<\w>>
B<C<[A-Za-z]>> vs. B<C<\p{IsAlphabetic}>>
B<C<[A-Z]>> vs. B<C<\p{IsUpper}>>
B<C<[a-z]>> vs. B<C<\p{IsLower}>>
B<C<[0-9]>> vs. B<C<\d>>
B<C<[^\w]>> vs. B<C<\W>>
B<C<[^\s]>> vs. B<C<\S>>
=head1 CONFIGURATION
This Policy is not configurable except for the standard options.
=head1 CREDITS
Initial development of this policy was supported by a grant from the
Perl Foundation.
=head1 AUTHOR
Chris Dolan <cdolan@cpan.org>
=head1 COPYRIGHT
Copyright (c) 2007-2023 Chris Dolan
This program is free software; you can redistribute it and/or modify
it under the same terms as Perl itself. The full text of this license
can be found in the LICENSE file included with this module
=cut
# Local Variables:
# mode: cperl
# cperl-indent-level: 4
# fill-column: 78
# indent-tabs-mode: nil
# c-indentation-style: bsd
# End:
# ex: set ts=8 sts=4 sw=4 tw=78 ft=perl expandtab shiftround :
|
