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 = '1.999_001';
12 $VERSION = eval $VERSION;
13 $VERSION = 2; # a bit of a cheat, but requesting v2 needs to be possible
15 our @WARNING_CATEGORIES = grep { exists $warnings::Offsets{$_} } qw(
20 experimental::autoderef
21 experimental::const_attr
22 experimental::lexical_subs
23 experimental::lexical_topic
24 experimental::postderef
25 experimental::re_strict
26 experimental::refaliasing
27 experimental::regex_sets
28 experimental::signatures
29 experimental::smartmatch
30 experimental::win32_perlio
90 if (defined $_[1] && eval { &UNIVERSAL::VERSION; 1}) {
92 unless _PERL_LT_5_8_4;
93 $^H{strictures_enable} = int $_[1];
96 _CAN_GOTO_VERSION ? goto &UNIVERSAL::VERSION : &UNIVERSAL::VERSION;
99 our %extra_load_states;
101 our $Smells_Like_VCS;
105 my %opts = ref $_[0] ? %{$_[0]} : @_;
106 if (!exists $opts{version}) {
108 = exists $^H{strictures_enable} ? delete $^H{strictures_enable}
111 $opts{file} = (caller)[1];
112 $class->_enable(\%opts);
116 my ($class, $opts) = @_;
117 my $version = $opts->{version};
119 if !defined $version;
120 my $method = "_enable_$version";
121 if (!$class->can($method)) {
123 Carp::croak("Major version specified as $version - not supported!");
125 $class->$method($opts);
129 my ($class, $opts) = @_;
131 warnings->import(FATAL => 'all');
133 if (_want_extra($opts->{file})) {
134 _load_extras(qw(indirect multidimensional bareword::filehandles));
135 indirect->unimport(':fatal')
136 if $extra_load_states{indirect};
137 multidimensional->unimport
138 if $extra_load_states{multidimensional};
139 bareword::filehandles->unimport
140 if $extra_load_states{'bareword::filehandles'};
144 our @V2_NONFATAL = grep { exists $warnings::Offsets{$_} } (
145 'exec', # not safe to catch
146 'recursion', # will be caught by other mechanisms
147 'internal', # not safe to catch
148 'malloc', # not safe to catch
149 'newline', # stat on nonexistent file with a newline in it
150 'experimental', # no reason for these to be fatal
151 'deprecated', # unfortunately can't make these fatal
152 'portable', # everything worked fine here, just may not elsewhere
154 our @V2_DISABLE = grep { exists $warnings::Offsets{$_} } (
155 'once' # triggers inconsistently, can't be fatalized
159 my ($class, $opts) = @_;
162 warnings->import(FATAL => @WARNING_CATEGORIES);
163 warnings->unimport(FATAL => @V2_NONFATAL);
164 warnings->import(@V2_NONFATAL);
165 warnings->unimport(@V2_DISABLE);
167 if (_want_extra($opts->{file})) {
168 _load_extras(qw(indirect multidimensional bareword::filehandles));
169 indirect->unimport(':fatal')
170 if $extra_load_states{indirect};
171 multidimensional->unimport
172 if $extra_load_states{multidimensional};
173 bareword::filehandles->unimport
174 if $extra_load_states{'bareword::filehandles'};
178 sub _want_extra_env {
179 if (exists $ENV{PERL_STRICTURES_EXTRA}) {
180 if (_PERL_LT_5_8_4 and $ENV{PERL_STRICTURES_EXTRA}) {
181 die 'PERL_STRICTURES_EXTRA checks are not available on perls older'
182 . "than 5.8.4: please unset \$ENV{PERL_STRICTURES_EXTRA}\n";
184 return $ENV{PERL_STRICTURES_EXTRA} ? 1 : 0;
191 my $want_env = _want_extra_env();
193 if defined $want_env;
196 and $file =~ /^(?:t|xt|lib|blib)[\\\/]/
197 and defined $Smells_Like_VCS ? $Smells_Like_VCS
198 : ( $Smells_Like_VCS = !!(
199 -e '.git' || -e '.svn' || -e '.hg'
200 || (-e '../../dist.ini'
201 && (-e '../../.git' || -e '../../.svn' || -e '../../.hg' ))
209 foreach my $mod (@extras) {
211 if exists $extra_load_states{$mod};
213 $extra_load_states{$mod} = eval "require $mod; 1;" or do {
216 #work around 5.8 require bug
217 (my $file = $mod) =~ s|::|/|g;
218 delete $INC{"${file}.pm"};
223 my $failed = join ' ', @failed;
224 my $extras = join ' ', @extras;
226 strictures.pm extra testing active but couldn't load all modules. Missing were:
230 Extra testing is auto-enabled in checkouts only, so if you're the author
231 of a strictures-using module you need to run:
235 but these modules are not required by your users.
245 strictures - turn on strict and make all warnings fatal
254 use warnings FATAL => 'all';
255 use warnings NONFATAL => qw(
267 except when called from a file which matches:
269 (caller)[1] =~ /^(?:t|xt|lib|blib)[\\\/]/
271 and when either C<.git>, C<.svn>, or C<.hg> is present in the current directory
272 (with the intention of only forcing extra tests on the author side) -- or when
273 C<.git>, C<.svn>, or C<.hg> is present two directories up along with
274 C<dist.ini> (which would indicate we are in a C<dzil test> operation, via
275 L<Dist::Zilla>) -- or when the C<PERL_STRICTURES_EXTRA> environment variable is
276 set, in which case it also does the equivalent of
280 no bareword::filehandles;
282 Note that C<PERL_STRICTURES_EXTRA> may at some point add even more tests, with
283 only a minor version increase, but any changes to the effect of C<use
284 strictures> in normal mode will involve a major version bump.
286 If any of the extra testing modules are not present, L<strictures> will
287 complain loudly, once, via C<warn()>, and then shut up. But you really
288 should consider installing them, they're all great anti-footgun tools.
292 I've been writing the equivalent of this module at the top of my code for
293 about a year now. I figured it was time to make it shorter.
295 Things like the importer in C<use Moose> don't help me because they turn
296 warnings on but don't make them fatal -- which from my point of view is
297 useless because I want an exception to tell me my code isn't warnings-clean.
299 Any time I see a warning from my code, that indicates a mistake.
301 Any time my code encounters a mistake, I want a crash -- not spew to STDERR
302 and then unknown (and probably undesired) subsequent behaviour.
304 I also want to ensure that obvious coding mistakes, like indirect object
305 syntax (and not so obvious mistakes that cause things to accidentally compile
306 as such) get caught, but not at the cost of an XS dependency and not at the
307 cost of blowing things up on another machine.
309 Therefore, L<strictures> turns on additional checking, but only when it thinks
310 it's running in a test file in a VCS checkout -- although if this causes
311 undesired behaviour this can be overridden by setting the
312 C<PERL_STRICTURES_EXTRA> environment variable.
314 If additional useful author side checks come to mind, I'll add them to the
315 C<PERL_STRICTURES_EXTRA> code path only -- this will result in a minor version
316 increase (e.g. 1.000000 to 1.001000 (1.1.0) or similar). Any fixes only to the
317 mechanism of this code will result in a sub-version increase (e.g. 1.000000 to
320 =head1 CATEGORY SELECTIONS
322 strictures does not enable fatal warnings for all categories.
328 Includes a warning that can cause your program to continue running
329 unintentionally after an internal fork. Not safe to fatalize.
333 Infinite recursion will end up overflowing the stack eventually anyway.
337 Triggers deep within perl, in places that are not safe to trap.
341 Triggers deep within perl, in places that are not safe to trap.
345 Includes a warning for using stat on a valid but suspect filename, ending in a
350 Experimental features are used intentionally.
354 Deprecations will inherently be added to in the future in unexpected ways,
355 so making them fatal won't be reliable.
359 Doesn't indicate an actual problem with the program, only that it may not
360 behave properly if run on a different machine.
364 Can't be fatalized. Also triggers very inconsistently, so we just disable it.
370 Depending on the version of strictures requested, different warnings will be
371 enabled. If no specific version is requested, the current version's behavior
372 will be used. Versions can be requested using perl's standard mechanism:
376 Or, by passing in a C<version> option:
378 use strictures version => 2;
385 use warnings FATAL => 'all';
386 use warnings NONFATAL => qw(
398 # and if in dev mode:
401 no bareword::filehandles;
403 Additionally, any warnings created by modules using L<warnings::register> or
404 C<warnings::register_categories()> will not be fatalized.
411 use warnings FATAL => 'all';
412 # and if in dev mode:
415 no bareword::filehandles;
421 This method does the setup work described above in L</DESCRIPTION>. Optionally
422 accepts a C<version> option to request a specific version's behavior.
426 This method traps the C<< strictures->VERSION(1) >> call produced by a use line
427 with a version number on it and does the version check.
429 =head1 EXTRA TESTING RATIONALE
431 Every so often, somebody complains that they're deploying via C<git pull>
432 and that they don't want L<strictures> to enable itself in this case -- and that
433 setting C<PERL_STRICTURES_EXTRA> to 0 isn't acceptable (additional ways to
434 disable extra testing would be welcome but the discussion never seems to get
437 In order to allow us to skip a couple of stages and get straight to a
438 productive conversation, here's my current rationale for turning the
439 extra testing on via a heuristic:
441 The extra testing is all stuff that only ever blows up at compile time;
442 this is intentional. So the oft-raised concern that it's different code being
443 tested is only sort of the case -- none of the modules involved affect the
444 final optree to my knowledge, so the author gets some additional compile
445 time crashes which he/she then fixes, and the rest of the testing is
446 completely valid for all environments.
448 The point of the extra testing -- especially C<no indirect> -- is to catch
449 mistakes that newbie users won't even realise are mistakes without
454 where foo is an & prototyped sub that you forgot to import -- this is
455 pernicious to track down since all I<seems> fine until it gets called
456 and you get a crash. Worse still, you can fail to have imported it due
457 to a circular require, at which point you have a load order dependent
458 bug which I've seen before now I<only> show up in production due to tiny
459 differences between the production and the development environment. I wrote
460 L<http://shadow.cat/blog/matt-s-trout/indirect-but-still-fatal/> to explain
461 this particular problem before L<strictures> itself existed.
463 As such, in my experience so far L<strictures>' extra testing has
464 I<avoided> production versus development differences, not caused them.
466 Additionally, L<strictures>' policy is very much "try and provide as much
467 protection as possible for newbies -- who won't think about whether there's
468 an option to turn on or not" -- so having only the environment variable
469 is not sufficient to achieve that (I get to explain that you need to add
470 C<use strict> at least once a week on freenode #perl -- newbies sometimes
471 completely skip steps because they don't understand that that step
474 I make no claims that the heuristic is perfect -- it's already been evolved
475 significantly over time, especially for 1.004 where we changed things to
476 ensure it only fires on files in your checkout (rather than L<strictures>-using
477 modules you happened to have installed, which was just silly). However, I
478 hope the above clarifies why a heuristic approach is not only necessary but
479 desirable from a point of view of providing new users with as much safety as
480 possible, and will allow any future discussion on the subject to focus on "how
481 do we minimise annoyance to people deploying from checkouts intentionally".
497 L<bareword::filehandles>
501 =head1 COMMUNITY AND SUPPORT
505 irc.perl.org #toolchain
507 (or bug 'mst' in query on there or freenode)
509 =head2 Git repository
511 Gitweb is on http://git.shadowcat.co.uk/ and the clone URL is:
513 git clone git://git.shadowcat.co.uk/p5sagit/strictures.git
515 The web interface to the repository is at:
517 http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=p5sagit/strictures.git
521 mst - Matt S. Trout (cpan:MSTROUT) <mst@shadowcat.co.uk>
525 Karen Etheridge (cpan:ETHER) <ether@cpan.org>
527 Mithaldu - Christian Walde (cpan:MITHALDU) <walde.christian@gmail.com>
529 haarg - Graham Knop (cpan:HAARG) <haarg@haarg.org>
533 Copyright (c) 2010 the strictures L</AUTHOR> and L</CONTRIBUTORS>
538 This library is free software and may be distributed under the same terms