4 use warnings FATAL => 'all';
7 *_PERL_LT_5_8_4 = ($] < 5.008004) ? sub(){1} : sub(){0};
10 our $VERSION = '1.005003'; # 1.5.3
13 my ($class, $version) = @_;
15 last unless defined && !ref && int != 1;
16 die "Major version specified as $_ - this is strictures version 1";
18 # passing undef here may either warn or die depending on the version of perl.
19 # we can't match the caller's warning state in this case, so just disable the
21 no warnings 'uninitialized';
22 shift->SUPER::VERSION(@_);
25 our $extra_load_states;
27 our $Smells_Like_VCS = (-e '.git' || -e '.svn' || -e '.hg'
28 || (-e '../../dist.ini'
29 && (-e '../../.git' || -e '../../.svn' || -e '../../.hg' )));
33 warnings->import(FATAL => 'all');
35 my $extra_tests = do {
36 if (exists $ENV{PERL_STRICTURES_EXTRA}) {
37 if (_PERL_LT_5_8_4 and $ENV{PERL_STRICTURES_EXTRA}) {
38 die 'PERL_STRICTURES_EXTRA checks are not available on perls older than 5.8.4: '
39 . "please unset \$ENV{PERL_STRICTURES_EXTRA}\n";
41 $ENV{PERL_STRICTURES_EXTRA};
42 } elsif (! _PERL_LT_5_8_4) {
43 !!((caller)[1] =~ /^(?:t|xt|lib|blib)/
48 $extra_load_states ||= do {
51 foreach my $mod (qw(indirect multidimensional bareword::filehandles)) {
52 eval "require $mod; \$rv{'$mod'} = 1;" or do {
55 # courtesy of the 5.8 require bug
56 # (we do a copy because 5.16.2 at least uses the same read-only
57 # scalars for the qw() list and it doesn't seem worth a $^V check)
59 (my $file = $mod) =~ s|::|/|g;
60 delete $INC{"${file}.pm"};
65 my $failed = join ' ', @failed;
67 strictures.pm extra testing active but couldn't load all modules. Missing were:
71 Extra testing is auto-enabled in checkouts only, so if you're the author
72 of a strictures-using module you need to run:
74 cpan indirect multidimensional bareword::filehandles
76 but these modules are not required by your users.
83 indirect->unimport(':fatal') if $extra_load_states->{indirect};
84 multidimensional->unimport if $extra_load_states->{multidimensional};
85 bareword::filehandles->unimport if $extra_load_states->{'bareword::filehandles'};
94 strictures - turn on strict and make all warnings fatal
103 use warnings FATAL => 'all';
105 except when called from a file which matches:
107 (caller)[1] =~ /^(?:t|xt|lib|blib)/
109 and when either C<.git>, C<.svn>, or C<.hg> is present in the current directory (with
110 the intention of only forcing extra tests on the author side) -- or when C<.git>,
111 C<.svn>, or C<.hg> is present two directories up along with C<dist.ini> (which would
112 indicate we are in a C<dzil test> operation, via L<Dist::Zilla>) --
113 or when the C<PERL_STRICTURES_EXTRA> environment variable is set, in which case
120 use warnings FATAL => 'all';
123 no bareword::filehandles;
125 Note that C<PERL_STRICTURES_EXTRA> may at some point add even more tests, with only a minor
126 version increase, but any changes to the effect of C<use strictures> in
127 normal mode will involve a major version bump.
129 If any of the extra testing modules are not present, L<strictures> will
130 complain loudly, once, via C<warn()>, and then shut up. But you really
131 should consider installing them, they're all great anti-footgun tools.
135 I've been writing the equivalent of this module at the top of my code for
136 about a year now. I figured it was time to make it shorter.
138 Things like the importer in C<use Moose> don't help me because they turn
139 warnings on but don't make them fatal -- which from my point of view is
140 useless because I want an exception to tell me my code isn't warnings-clean.
142 Any time I see a warning from my code, that indicates a mistake.
144 Any time my code encounters a mistake, I want a crash -- not spew to STDERR
145 and then unknown (and probably undesired) subsequent behaviour.
147 I also want to ensure that obvious coding mistakes, like indirect object
148 syntax (and not so obvious mistakes that cause things to accidentally compile
149 as such) get caught, but not at the cost of an XS dependency and not at the
150 cost of blowing things up on another machine.
152 Therefore, L<strictures> turns on additional checking, but only when it thinks
153 it's running in a test file in a VCS checkout -- although if this causes
154 undesired behaviour this can be overridden by setting the
155 C<PERL_STRICTURES_EXTRA> environment variable.
157 If additional useful author side checks come to mind, I'll add them to the
158 C<PERL_STRICTURES_EXTRA> code path only -- this will result in a minor version increase (e.g.
159 1.000000 to 1.001000 (1.1.0) or similar). Any fixes only to the mechanism of
160 this code will result in a sub-version increase (e.g. 1.000000 to 1.000001
163 If the behaviour of C<use strictures> in normal mode changes in any way, that
164 will constitute a major version increase -- and the code already checks
165 when its version is tested to ensure that
169 will continue to only introduce the current set of strictures even if 2.0 is
176 This method does the setup work described above in L</DESCRIPTION>
180 This method traps the C<< strictures->VERSION(1) >> call produced by a use line
181 with a version number on it and does the version check.
183 =head1 EXTRA TESTING RATIONALE
185 Every so often, somebody complains that they're deploying via C<git pull>
186 and that they don't want L<strictures> to enable itself in this case -- and that
187 setting C<PERL_STRICTURES_EXTRA> to 0 isn't acceptable (additional ways to
188 disable extra testing would be welcome but the discussion never seems to get
191 In order to allow us to skip a couple of stages and get straight to a
192 productive conversation, here's my current rationale for turning the
193 extra testing on via a heuristic:
195 The extra testing is all stuff that only ever blows up at compile time;
196 this is intentional. So the oft-raised concern that it's different code being
197 tested is only sort of the case -- none of the modules involved affect the
198 final optree to my knowledge, so the author gets some additional compile
199 time crashes which he/she then fixes, and the rest of the testing is
200 completely valid for all environments.
202 The point of the extra testing -- especially C<no indirect> -- is to catch
203 mistakes that newbie users won't even realise are mistakes without
208 where foo is an & prototyped sub that you forgot to import -- this is
209 pernicious to track down since all I<seems> fine until it gets called
210 and you get a crash. Worse still, you can fail to have imported it due
211 to a circular require, at which point you have a load order dependent
212 bug which I've seen before now I<only> show up in production due to tiny
213 differences between the production and the development environment. I wrote
214 L<http://shadow.cat/blog/matt-s-trout/indirect-but-still-fatal/> to explain
215 this particular problem before L<strictures> itself existed.
217 As such, in my experience so far L<strictures>' extra testing has
218 I<avoided> production versus development differences, not caused them.
220 Additionally, L<strictures>' policy is very much "try and provide as much
221 protection as possible for newbies -- who won't think about whether there's
222 an option to turn on or not" -- so having only the environment variable
223 is not sufficient to achieve that (I get to explain that you need to add
224 C<use strict> at least once a week on freenode #perl -- newbies sometimes
225 completely skip steps because they don't understand that that step
228 I make no claims that the heuristic is perfect -- it's already been evolved
229 significantly over time, especially for 1.004 where we changed things to
230 ensure it only fires on files in your checkout (rather than L<strictures>-using
231 modules you happened to have installed, which was just silly). However, I
232 hope the above clarifies why a heuristic approach is not only necessary but
233 desirable from a point of view of providing new users with as much safety as possible,
234 and will allow any future discussion on the subject to focus on "how do we
235 minimise annoyance to people deploying from checkouts intentionally".
251 L<bareword::filehandles>
255 =head1 COMMUNITY AND SUPPORT
259 irc.perl.org #toolchain
261 (or bug 'mst' in query on there or freenode)
263 =head2 Git repository
265 Gitweb is on http://git.shadowcat.co.uk/ and the clone URL is:
267 git clone git://git.shadowcat.co.uk/p5sagit/strictures.git
269 The web interface to the repository is at:
271 http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=p5sagit/strictures.git
275 mst - Matt S. Trout (cpan:MSTROUT) <mst@shadowcat.co.uk>
279 Karen Etheridge (cpan:ETHER) <ether@cpan.org>
281 Mithaldu - Christian Walde (cpan:MITHALDU) <walde.christian@gmail.com>
283 haarg - Graham Knop (cpan:HAARG) <haarg@haarg.org>
287 Copyright (c) 2010 the strictures L</AUTHOR> and L</CONTRIBUTORS>
292 This library is free software and may be distributed under the same terms