4 use warnings FATAL => 'all';
7 *_PERL_LT_5_8_4 = ($] < 5.008004) ? sub(){1} : sub(){0};
10 our $VERSION = '2.000000';
11 $VERSION = eval $VERSION;
13 our @WARNING_CATEGORIES = grep { exists $warnings::Offsets{$_} } qw(
18 experimental::lexical_subs
19 experimental::lexical_topic
20 experimental::regex_sets
21 experimental::smartmatch
75 if (defined $_[1] && eval { $_[0]->UNIVERSAL::VERSION($_[1]); 1}) {
77 unless _PERL_LT_5_8_4;
78 $^H{strictures_enable} = int $_[1];
80 goto &UNIVERSAL::VERSION;
83 our %extra_load_states;
89 my %opts = ref $_[0] ? %{$_[0]} : @_;
90 if (!exists $opts{version}) {
92 = exists $^H{strictures_enable} ? delete $^H{strictures_enable}
95 $opts{file} = (caller)[1];
96 $class->_enable(\%opts);
100 my ($class, $opts) = @_;
101 my $version = $opts->{version};
103 if !defined $version;
104 my $method = "_enable_$version";
105 if (!$class->can($method)) {
107 Carp::croak("Major version specified as $version - not supported!");
109 $class->$method($opts);
113 my ($class, $opts) = @_;
115 warnings->import(FATAL => 'all');
117 if (_want_extra($opts->{file})) {
118 _load_extras(qw(indirect multidimensional bareword::filehandles));
119 indirect->unimport(':fatal')
120 if $extra_load_states{indirect};
121 multidimensional->unimport
122 if $extra_load_states{multidimensional};
123 bareword::filehandles->unimport
124 if $extra_load_states{'bareword::filehandles'};
128 our @V2_NONFATAL = grep { exists $warnings::Offsets{$_} } qw(
138 our @V2_DISABLE = grep { exists $warnings::Offsets{$_} } qw(
143 my ($class, $opts) = @_;
146 warnings->import(FATAL => @WARNING_CATEGORIES);
147 warnings->import(NONFATAL => @V2_NONFATAL);
148 warnings->unimport(@V2_DISABLE);
150 if (_want_extra($opts->{file})) {
151 _load_extras(qw(indirect multidimensional bareword::filehandles));
152 indirect->unimport(':fatal')
153 if $extra_load_states{indirect};
154 multidimensional->unimport
155 if $extra_load_states{multidimensional};
156 bareword::filehandles->unimport
157 if $extra_load_states{'bareword::filehandles'};
161 sub _want_extra_env {
162 if (exists $ENV{PERL_STRICTURES_EXTRA}) {
163 if (_PERL_LT_5_8_4 and $ENV{PERL_STRICTURES_EXTRA}) {
164 die 'PERL_STRICTURES_EXTRA checks are not available on perls older'
165 . "than 5.8.4: please unset \$ENV{PERL_STRICTURES_EXTRA}\n";
167 return $ENV{PERL_STRICTURES_EXTRA} ? 1 : 0;
174 my $want_env = _want_extra_env();
176 if defined $want_env;
179 and $file =~ /^(?:t|xt|lib|blib)[\\\/]/
180 and defined $Smells_Like_VCS ? $Smells_Like_VCS
181 : ( $Smells_Like_VCS = !!(
182 -e '.git' || -e '.svn' || -e '.hg'
183 || (-e '../../dist.ini'
184 && (-e '../../.git' || -e '../../.svn' || -e '../../.hg' ))
192 foreach my $mod (@extras) {
194 if exists $extra_load_states{$mod};
196 $extra_load_states{$mod} = eval "require $mod; 1;" or do {
199 #work around 5.8 require bug
200 (my $file = $mod) =~ s|::|/|g;
201 delete $INC{"${file}.pm"};
206 my $failed = join ' ', @failed;
207 my $extras = join ' ', @extras;
209 strictures.pm extra testing active but couldn't load all modules. Missing were:
213 Extra testing is auto-enabled in checkouts only, so if you're the author
214 of a strictures-using module you need to run:
218 but these modules are not required by your users.
228 strictures - turn on strict and make all warnings fatal
237 use warnings FATAL => 'all';
239 except when called from a file which matches:
241 (caller)[1] =~ /^(?:t|xt|lib|blib)[\\\/]/
243 and when either C<.git>, C<.svn>, or C<.hg> is present in the current directory
244 (with the intention of only forcing extra tests on the author side) -- or when
245 C<.git>, C<.svn>, or C<.hg> is present two directories up along with
246 C<dist.ini> (which would indicate we are in a C<dzil test> operation, via
247 L<Dist::Zilla>) -- or when the C<PERL_STRICTURES_EXTRA> environment variable is
255 use warnings FATAL => 'all';
258 no bareword::filehandles;
260 Note that C<PERL_STRICTURES_EXTRA> may at some point add even more tests, with
261 only a minor version increase, but any changes to the effect of C<use
262 strictures> in normal mode will involve a major version bump.
264 If any of the extra testing modules are not present, L<strictures> will
265 complain loudly, once, via C<warn()>, and then shut up. But you really
266 should consider installing them, they're all great anti-footgun tools.
270 I've been writing the equivalent of this module at the top of my code for
271 about a year now. I figured it was time to make it shorter.
273 Things like the importer in C<use Moose> don't help me because they turn
274 warnings on but don't make them fatal -- which from my point of view is
275 useless because I want an exception to tell me my code isn't warnings-clean.
277 Any time I see a warning from my code, that indicates a mistake.
279 Any time my code encounters a mistake, I want a crash -- not spew to STDERR
280 and then unknown (and probably undesired) subsequent behaviour.
282 I also want to ensure that obvious coding mistakes, like indirect object
283 syntax (and not so obvious mistakes that cause things to accidentally compile
284 as such) get caught, but not at the cost of an XS dependency and not at the
285 cost of blowing things up on another machine.
287 Therefore, L<strictures> turns on additional checking, but only when it thinks
288 it's running in a test file in a VCS checkout -- although if this causes
289 undesired behaviour this can be overridden by setting the
290 C<PERL_STRICTURES_EXTRA> environment variable.
292 If additional useful author side checks come to mind, I'll add them to the
293 C<PERL_STRICTURES_EXTRA> code path only -- this will result in a minor version
294 increase (e.g. 1.000000 to 1.001000 (1.1.0) or similar). Any fixes only to the
295 mechanism of this code will result in a sub-version increase (e.g. 1.000000 to
298 If the behaviour of C<use strictures> in normal mode changes in any way, that
299 will constitute a major version increase -- and the code already checks
300 when its version is tested to ensure that
304 will continue to only introduce the current set of strictures even if 2.0 is
311 This method does the setup work described above in L</DESCRIPTION>
315 This method traps the C<< strictures->VERSION(1) >> call produced by a use line
316 with a version number on it and does the version check.
318 =head1 EXTRA TESTING RATIONALE
320 Every so often, somebody complains that they're deploying via C<git pull>
321 and that they don't want L<strictures> to enable itself in this case -- and that
322 setting C<PERL_STRICTURES_EXTRA> to 0 isn't acceptable (additional ways to
323 disable extra testing would be welcome but the discussion never seems to get
326 In order to allow us to skip a couple of stages and get straight to a
327 productive conversation, here's my current rationale for turning the
328 extra testing on via a heuristic:
330 The extra testing is all stuff that only ever blows up at compile time;
331 this is intentional. So the oft-raised concern that it's different code being
332 tested is only sort of the case -- none of the modules involved affect the
333 final optree to my knowledge, so the author gets some additional compile
334 time crashes which he/she then fixes, and the rest of the testing is
335 completely valid for all environments.
337 The point of the extra testing -- especially C<no indirect> -- is to catch
338 mistakes that newbie users won't even realise are mistakes without
343 where foo is an & prototyped sub that you forgot to import -- this is
344 pernicious to track down since all I<seems> fine until it gets called
345 and you get a crash. Worse still, you can fail to have imported it due
346 to a circular require, at which point you have a load order dependent
347 bug which I've seen before now I<only> show up in production due to tiny
348 differences between the production and the development environment. I wrote
349 L<http://shadow.cat/blog/matt-s-trout/indirect-but-still-fatal/> to explain
350 this particular problem before L<strictures> itself existed.
352 As such, in my experience so far L<strictures>' extra testing has
353 I<avoided> production versus development differences, not caused them.
355 Additionally, L<strictures>' policy is very much "try and provide as much
356 protection as possible for newbies -- who won't think about whether there's
357 an option to turn on or not" -- so having only the environment variable
358 is not sufficient to achieve that (I get to explain that you need to add
359 C<use strict> at least once a week on freenode #perl -- newbies sometimes
360 completely skip steps because they don't understand that that step
363 I make no claims that the heuristic is perfect -- it's already been evolved
364 significantly over time, especially for 1.004 where we changed things to
365 ensure it only fires on files in your checkout (rather than L<strictures>-using
366 modules you happened to have installed, which was just silly). However, I
367 hope the above clarifies why a heuristic approach is not only necessary but
368 desirable from a point of view of providing new users with as much safety as
369 possible, and will allow any future discussion on the subject to focus on "how
370 do we minimise annoyance to people deploying from checkouts intentionally".
386 L<bareword::filehandles>
390 =head1 COMMUNITY AND SUPPORT
394 irc.perl.org #toolchain
396 (or bug 'mst' in query on there or freenode)
398 =head2 Git repository
400 Gitweb is on http://git.shadowcat.co.uk/ and the clone URL is:
402 git clone git://git.shadowcat.co.uk/p5sagit/strictures.git
404 The web interface to the repository is at:
406 http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=p5sagit/strictures.git
410 mst - Matt S. Trout (cpan:MSTROUT) <mst@shadowcat.co.uk>
414 Karen Etheridge (cpan:ETHER) <ether@cpan.org>
416 Mithaldu - Christian Walde (cpan:MITHALDU) <walde.christian@gmail.com>
418 haarg - Graham Knop (cpan:HAARG) <haarg@haarg.org>
422 Copyright (c) 2010 the strictures L</AUTHOR> and L</CONTRIBUTORS>
427 This library is free software and may be distributed under the same terms