4 use warnings FATAL => 'all';
7 *_PERL_LT_5_8_4 = ($] < 5.008004) ? sub(){1} : sub(){0};
8 *_CAN_GOTO_VERSION = ($] >= 5.008000) ? sub(){1} : sub(){0};
11 our $VERSION = '2.000000';
12 $VERSION = eval $VERSION;
14 our @WARNING_CATEGORIES = grep { exists $warnings::Offsets{$_} } qw(
20 experimental::autoderef
22 experimental::const_attr
23 experimental::lexical_subs
24 experimental::lexical_topic
25 experimental::postderef
26 experimental::re_strict
27 experimental::refaliasing
28 experimental::regex_sets
29 experimental::signatures
30 experimental::smartmatch
31 experimental::win32_perlio
92 if (defined $_[1] && eval { &UNIVERSAL::VERSION; 1}) {
94 unless _PERL_LT_5_8_4;
95 $^H{strictures_enable} = int $_[1];
98 _CAN_GOTO_VERSION ? goto &UNIVERSAL::VERSION : &UNIVERSAL::VERSION;
101 our %extra_load_states;
103 our $Smells_Like_VCS;
107 my %opts = ref $_[0] ? %{$_[0]} : @_;
108 if (!exists $opts{version}) {
110 = exists $^H{strictures_enable} ? delete $^H{strictures_enable}
113 $opts{file} = (caller)[1];
114 $class->_enable(\%opts);
118 my ($class, $opts) = @_;
119 my $version = $opts->{version};
121 if !defined $version;
122 my $method = "_enable_$version";
123 if (!$class->can($method)) {
125 Carp::croak("Major version specified as $version - not supported!");
127 $class->$method($opts);
131 my ($class, $opts) = @_;
133 warnings->import(FATAL => 'all');
135 if (_want_extra($opts->{file})) {
136 _load_extras(qw(indirect multidimensional bareword::filehandles));
137 indirect->unimport(':fatal')
138 if $extra_load_states{indirect};
139 multidimensional->unimport
140 if $extra_load_states{multidimensional};
141 bareword::filehandles->unimport
142 if $extra_load_states{'bareword::filehandles'};
146 our @V2_NONFATAL = grep { exists $warnings::Offsets{$_} } (
147 'exec', # not safe to catch
148 'recursion', # will be caught by other mechanisms
149 'internal', # not safe to catch
150 'malloc', # not safe to catch
151 'newline', # stat on nonexistent file with a newline in it
152 'experimental', # no reason for these to be fatal
153 'deprecated', # unfortunately can't make these fatal
154 'portable', # everything worked fine here, just may not elsewhere
156 our @V2_DISABLE = grep { exists $warnings::Offsets{$_} } (
157 'once' # triggers inconsistently, can't be fatalized
161 my ($class, $opts) = @_;
164 warnings->import(FATAL => @WARNING_CATEGORIES);
165 warnings->unimport(FATAL => @V2_NONFATAL);
166 warnings->import(@V2_NONFATAL);
167 warnings->unimport(@V2_DISABLE);
169 if (_want_extra($opts->{file})) {
170 _load_extras(qw(indirect multidimensional bareword::filehandles));
171 indirect->unimport(':fatal')
172 if $extra_load_states{indirect};
173 multidimensional->unimport
174 if $extra_load_states{multidimensional};
175 bareword::filehandles->unimport
176 if $extra_load_states{'bareword::filehandles'};
180 sub _want_extra_env {
181 if (exists $ENV{PERL_STRICTURES_EXTRA}) {
182 if (_PERL_LT_5_8_4 and $ENV{PERL_STRICTURES_EXTRA}) {
183 die 'PERL_STRICTURES_EXTRA checks are not available on perls older'
184 . "than 5.8.4: please unset \$ENV{PERL_STRICTURES_EXTRA}\n";
186 return $ENV{PERL_STRICTURES_EXTRA} ? 1 : 0;
193 my $want_env = _want_extra_env();
195 if defined $want_env;
198 and $file =~ /^(?:t|xt|lib|blib)[\\\/]/
199 and defined $Smells_Like_VCS ? $Smells_Like_VCS
200 : ( $Smells_Like_VCS = !!(
201 -e '.git' || -e '.svn' || -e '.hg' || -e '.bzr'
202 || (-e '../../dist.ini'
203 && (-e '../../.git' || -e '../../.svn' || -e '../../.hg' || -e '../../.bzr' ))
211 foreach my $mod (@extras) {
213 if exists $extra_load_states{$mod};
215 $extra_load_states{$mod} = eval "require $mod; 1;" or do {
218 #work around 5.8 require bug
219 (my $file = $mod) =~ s|::|/|g;
220 delete $INC{"${file}.pm"};
225 my $failed = join ' ', @failed;
226 my $extras = join ' ', @extras;
228 strictures.pm extra testing active but couldn't load all modules. Missing were:
232 Extra testing is auto-enabled in checkouts only, so if you're the author
233 of a strictures-using module you need to run:
237 but these modules are not required by your users.
247 strictures - turn on strict and make all warnings fatal
256 use warnings FATAL => 'all';
257 use warnings NONFATAL => qw(
269 except when called from a file which matches:
271 (caller)[1] =~ /^(?:t|xt|lib|blib)[\\\/]/
273 and when either C<.git>, C<.svn>, C<.hg>, or C<.bzr> is present in the current
274 directory (with the intention of only forcing extra tests on the author side)
275 -- or when C<.git>, C<.svn>, C<.hg>, or C<.bzr> is present two directories up
276 along with C<dist.ini> (which would indicate we are in a C<dzil test> operation,
277 via L<Dist::Zilla>) -- or when the C<PERL_STRICTURES_EXTRA> environment variable
278 is set, in which case it also does the equivalent of
282 no bareword::filehandles;
284 Note that C<PERL_STRICTURES_EXTRA> may at some point add even more tests, with
285 only a minor version increase, but any changes to the effect of C<use
286 strictures> in normal mode will involve a major version bump.
288 If any of the extra testing modules are not present, L<strictures> will
289 complain loudly, once, via C<warn()>, and then shut up. But you really
290 should consider installing them, they're all great anti-footgun tools.
294 I've been writing the equivalent of this module at the top of my code for
295 about a year now. I figured it was time to make it shorter.
297 Things like the importer in C<use Moose> don't help me because they turn
298 warnings on but don't make them fatal -- which from my point of view is
299 useless because I want an exception to tell me my code isn't warnings-clean.
301 Any time I see a warning from my code, that indicates a mistake.
303 Any time my code encounters a mistake, I want a crash -- not spew to STDERR
304 and then unknown (and probably undesired) subsequent behaviour.
306 I also want to ensure that obvious coding mistakes, like indirect object
307 syntax (and not so obvious mistakes that cause things to accidentally compile
308 as such) get caught, but not at the cost of an XS dependency and not at the
309 cost of blowing things up on another machine.
311 Therefore, L<strictures> turns on additional checking, but only when it thinks
312 it's running in a test file in a VCS checkout -- although if this causes
313 undesired behaviour this can be overridden by setting the
314 C<PERL_STRICTURES_EXTRA> environment variable.
316 If additional useful author side checks come to mind, I'll add them to the
317 C<PERL_STRICTURES_EXTRA> code path only -- this will result in a minor version
318 increase (e.g. 1.000000 to 1.001000 (1.1.0) or similar). Any fixes only to the
319 mechanism of this code will result in a sub-version increase (e.g. 1.000000 to
322 =head1 CATEGORY SELECTIONS
324 strictures does not enable fatal warnings for all categories.
330 Includes a warning that can cause your program to continue running
331 unintentionally after an internal fork. Not safe to fatalize.
335 Infinite recursion will end up overflowing the stack eventually anyway.
339 Triggers deep within perl, in places that are not safe to trap.
343 Triggers deep within perl, in places that are not safe to trap.
347 Includes a warning for using stat on a valid but suspect filename, ending in a
352 Experimental features are used intentionally.
356 Deprecations will inherently be added to in the future in unexpected ways,
357 so making them fatal won't be reliable.
361 Doesn't indicate an actual problem with the program, only that it may not
362 behave properly if run on a different machine.
366 Can't be fatalized. Also triggers very inconsistently, so we just disable it.
372 Depending on the version of strictures requested, different warnings will be
373 enabled. If no specific version is requested, the current version's behavior
374 will be used. Versions can be requested using perl's standard mechanism:
378 Or, by passing in a C<version> option:
380 use strictures version => 2;
387 use warnings FATAL => 'all';
388 use warnings NONFATAL => qw(
400 # and if in dev mode:
403 no bareword::filehandles;
405 Additionally, any warnings created by modules using L<warnings::register> or
406 C<warnings::register_categories()> will not be fatalized.
413 use warnings FATAL => 'all';
414 # and if in dev mode:
417 no bareword::filehandles;
423 This method does the setup work described above in L</DESCRIPTION>. Optionally
424 accepts a C<version> option to request a specific version's behavior.
428 This method traps the C<< strictures->VERSION(1) >> call produced by a use line
429 with a version number on it and does the version check.
431 =head1 EXTRA TESTING RATIONALE
433 Every so often, somebody complains that they're deploying via C<git pull>
434 and that they don't want L<strictures> to enable itself in this case -- and that
435 setting C<PERL_STRICTURES_EXTRA> to 0 isn't acceptable (additional ways to
436 disable extra testing would be welcome but the discussion never seems to get
439 In order to allow us to skip a couple of stages and get straight to a
440 productive conversation, here's my current rationale for turning the
441 extra testing on via a heuristic:
443 The extra testing is all stuff that only ever blows up at compile time;
444 this is intentional. So the oft-raised concern that it's different code being
445 tested is only sort of the case -- none of the modules involved affect the
446 final optree to my knowledge, so the author gets some additional compile
447 time crashes which he/she then fixes, and the rest of the testing is
448 completely valid for all environments.
450 The point of the extra testing -- especially C<no indirect> -- is to catch
451 mistakes that newbie users won't even realise are mistakes without
456 where foo is an & prototyped sub that you forgot to import -- this is
457 pernicious to track down since all I<seems> fine until it gets called
458 and you get a crash. Worse still, you can fail to have imported it due
459 to a circular require, at which point you have a load order dependent
460 bug which I've seen before now I<only> show up in production due to tiny
461 differences between the production and the development environment. I wrote
462 L<http://shadow.cat/blog/matt-s-trout/indirect-but-still-fatal/> to explain
463 this particular problem before L<strictures> itself existed.
465 As such, in my experience so far L<strictures>' extra testing has
466 I<avoided> production versus development differences, not caused them.
468 Additionally, L<strictures>' policy is very much "try and provide as much
469 protection as possible for newbies -- who won't think about whether there's
470 an option to turn on or not" -- so having only the environment variable
471 is not sufficient to achieve that (I get to explain that you need to add
472 C<use strict> at least once a week on freenode #perl -- newbies sometimes
473 completely skip steps because they don't understand that that step
476 I make no claims that the heuristic is perfect -- it's already been evolved
477 significantly over time, especially for 1.004 where we changed things to
478 ensure it only fires on files in your checkout (rather than L<strictures>-using
479 modules you happened to have installed, which was just silly). However, I
480 hope the above clarifies why a heuristic approach is not only necessary but
481 desirable from a point of view of providing new users with as much safety as
482 possible, and will allow any future discussion on the subject to focus on "how
483 do we minimise annoyance to people deploying from checkouts intentionally".
499 L<bareword::filehandles>
503 =head1 COMMUNITY AND SUPPORT
507 irc.perl.org #toolchain
509 (or bug 'mst' in query on there or freenode)
511 =head2 Git repository
513 Gitweb is on http://git.shadowcat.co.uk/ and the clone URL is:
515 git clone git://git.shadowcat.co.uk/p5sagit/strictures.git
517 The web interface to the repository is at:
519 http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=p5sagit/strictures.git
523 mst - Matt S. Trout (cpan:MSTROUT) <mst@shadowcat.co.uk>
527 Karen Etheridge (cpan:ETHER) <ether@cpan.org>
529 Mithaldu - Christian Walde (cpan:MITHALDU) <walde.christian@gmail.com>
531 haarg - Graham Knop (cpan:HAARG) <haarg@haarg.org>
535 Copyright (c) 2010 the strictures L</AUTHOR> and L</CONTRIBUTORS>
540 This library is free software and may be distributed under the same terms