4 use warnings FATAL => 'all';
7 *_PERL_LT_5_8_4 = ($] < 5.008004) ? sub(){1} : sub(){0};
10 our $VERSION = '1.005006';
11 $VERSION = eval $VERSION;
16 if (defined $_[1] && eval { $_[0]->UNIVERSAL::VERSION($_[1]); 1}) {
18 unless _PERL_LT_5_8_4;
19 $^H{strictures_enable} = int $_[1];
21 goto &UNIVERSAL::VERSION;
24 our %extra_load_states;
30 my %opts = ref $_[0] ? %{$_[0]} : @_;
31 if (!exists $opts{version}) {
33 = exists $^H{strictures_enable} ? delete $^H{strictures_enable}
36 $opts{file} = (caller)[1];
37 $class->_enable(\%opts);
41 my ($class, $opts) = @_;
42 my $version = $opts->{version};
45 my $method = "_enable_$version";
46 if (!$class->can($method)) {
48 Carp::croak("Major version specified as $version - not supported!");
50 $class->$method($opts);
54 my ($class, $opts) = @_;
56 warnings->import(FATAL => 'all');
58 if (_want_extra($opts->{file})) {
59 _load_extras(qw(indirect multidimensional bareword::filehandles));
60 indirect->unimport(':fatal')
61 if $extra_load_states{indirect};
62 multidimensional->unimport
63 if $extra_load_states{multidimensional};
64 bareword::filehandles->unimport
65 if $extra_load_states{'bareword::filehandles'};
70 if (exists $ENV{PERL_STRICTURES_EXTRA}) {
71 if (_PERL_LT_5_8_4 and $ENV{PERL_STRICTURES_EXTRA}) {
72 die 'PERL_STRICTURES_EXTRA checks are not available on perls older'
73 . "than 5.8.4: please unset \$ENV{PERL_STRICTURES_EXTRA}\n";
75 return $ENV{PERL_STRICTURES_EXTRA} ? 1 : 0;
82 my $want_env = _want_extra_env();
87 and $file =~ /^(?:t|xt|lib|blib)[\\\/]/
88 and defined $Smells_Like_VCS ? $Smells_Like_VCS
89 : ( $Smells_Like_VCS = !!(
90 -e '.git' || -e '.svn' || -e '.hg'
91 || (-e '../../dist.ini'
92 && (-e '../../.git' || -e '../../.svn' || -e '../../.hg' ))
100 foreach my $mod (@extras) {
102 if exists $extra_load_states{$mod};
104 $extra_load_states{$mod} = eval "require $mod; 1;" or do {
107 #work around 5.8 require bug
108 (my $file = $mod) =~ s|::|/|g;
109 delete $INC{"${file}.pm"};
114 my $failed = join ' ', @failed;
115 my $extras = join ' ', @extras;
117 strictures.pm extra testing active but couldn't load all modules. Missing were:
121 Extra testing is auto-enabled in checkouts only, so if you're the author
122 of a strictures-using module you need to run:
126 but these modules are not required by your users.
136 strictures - turn on strict and make all warnings fatal
145 use warnings FATAL => 'all';
147 except when called from a file which matches:
149 (caller)[1] =~ /^(?:t|xt|lib|blib)[\\\/]/
151 and when either C<.git>, C<.svn>, or C<.hg> is present in the current directory
152 (with the intention of only forcing extra tests on the author side) -- or when
153 C<.git>, C<.svn>, or C<.hg> is present two directories up along with
154 C<dist.ini> (which would indicate we are in a C<dzil test> operation, via
155 L<Dist::Zilla>) -- or when the C<PERL_STRICTURES_EXTRA> environment variable is
163 use warnings FATAL => 'all';
166 no bareword::filehandles;
168 Note that C<PERL_STRICTURES_EXTRA> may at some point add even more tests, with
169 only a minor version increase, but any changes to the effect of C<use
170 strictures> in normal mode will involve a major version bump.
172 If any of the extra testing modules are not present, L<strictures> will
173 complain loudly, once, via C<warn()>, and then shut up. But you really
174 should consider installing them, they're all great anti-footgun tools.
178 I've been writing the equivalent of this module at the top of my code for
179 about a year now. I figured it was time to make it shorter.
181 Things like the importer in C<use Moose> don't help me because they turn
182 warnings on but don't make them fatal -- which from my point of view is
183 useless because I want an exception to tell me my code isn't warnings-clean.
185 Any time I see a warning from my code, that indicates a mistake.
187 Any time my code encounters a mistake, I want a crash -- not spew to STDERR
188 and then unknown (and probably undesired) subsequent behaviour.
190 I also want to ensure that obvious coding mistakes, like indirect object
191 syntax (and not so obvious mistakes that cause things to accidentally compile
192 as such) get caught, but not at the cost of an XS dependency and not at the
193 cost of blowing things up on another machine.
195 Therefore, L<strictures> turns on additional checking, but only when it thinks
196 it's running in a test file in a VCS checkout -- although if this causes
197 undesired behaviour this can be overridden by setting the
198 C<PERL_STRICTURES_EXTRA> environment variable.
200 If additional useful author side checks come to mind, I'll add them to the
201 C<PERL_STRICTURES_EXTRA> code path only -- this will result in a minor version
202 increase (e.g. 1.000000 to 1.001000 (1.1.0) or similar). Any fixes only to the
203 mechanism of this code will result in a sub-version increase (e.g. 1.000000 to
206 If the behaviour of C<use strictures> in normal mode changes in any way, that
207 will constitute a major version increase -- and the code already checks
208 when its version is tested to ensure that
212 will continue to only introduce the current set of strictures even if 2.0 is
219 This method does the setup work described above in L</DESCRIPTION>
223 This method traps the C<< strictures->VERSION(1) >> call produced by a use line
224 with a version number on it and does the version check.
226 =head1 EXTRA TESTING RATIONALE
228 Every so often, somebody complains that they're deploying via C<git pull>
229 and that they don't want L<strictures> to enable itself in this case -- and that
230 setting C<PERL_STRICTURES_EXTRA> to 0 isn't acceptable (additional ways to
231 disable extra testing would be welcome but the discussion never seems to get
234 In order to allow us to skip a couple of stages and get straight to a
235 productive conversation, here's my current rationale for turning the
236 extra testing on via a heuristic:
238 The extra testing is all stuff that only ever blows up at compile time;
239 this is intentional. So the oft-raised concern that it's different code being
240 tested is only sort of the case -- none of the modules involved affect the
241 final optree to my knowledge, so the author gets some additional compile
242 time crashes which he/she then fixes, and the rest of the testing is
243 completely valid for all environments.
245 The point of the extra testing -- especially C<no indirect> -- is to catch
246 mistakes that newbie users won't even realise are mistakes without
251 where foo is an & prototyped sub that you forgot to import -- this is
252 pernicious to track down since all I<seems> fine until it gets called
253 and you get a crash. Worse still, you can fail to have imported it due
254 to a circular require, at which point you have a load order dependent
255 bug which I've seen before now I<only> show up in production due to tiny
256 differences between the production and the development environment. I wrote
257 L<http://shadow.cat/blog/matt-s-trout/indirect-but-still-fatal/> to explain
258 this particular problem before L<strictures> itself existed.
260 As such, in my experience so far L<strictures>' extra testing has
261 I<avoided> production versus development differences, not caused them.
263 Additionally, L<strictures>' policy is very much "try and provide as much
264 protection as possible for newbies -- who won't think about whether there's
265 an option to turn on or not" -- so having only the environment variable
266 is not sufficient to achieve that (I get to explain that you need to add
267 C<use strict> at least once a week on freenode #perl -- newbies sometimes
268 completely skip steps because they don't understand that that step
271 I make no claims that the heuristic is perfect -- it's already been evolved
272 significantly over time, especially for 1.004 where we changed things to
273 ensure it only fires on files in your checkout (rather than L<strictures>-using
274 modules you happened to have installed, which was just silly). However, I
275 hope the above clarifies why a heuristic approach is not only necessary but
276 desirable from a point of view of providing new users with as much safety as
277 possible, and will allow any future discussion on the subject to focus on "how
278 do we minimise annoyance to people deploying from checkouts intentionally".
294 L<bareword::filehandles>
298 =head1 COMMUNITY AND SUPPORT
302 irc.perl.org #toolchain
304 (or bug 'mst' in query on there or freenode)
306 =head2 Git repository
308 Gitweb is on http://git.shadowcat.co.uk/ and the clone URL is:
310 git clone git://git.shadowcat.co.uk/p5sagit/strictures.git
312 The web interface to the repository is at:
314 http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=p5sagit/strictures.git
318 mst - Matt S. Trout (cpan:MSTROUT) <mst@shadowcat.co.uk>
322 Karen Etheridge (cpan:ETHER) <ether@cpan.org>
324 Mithaldu - Christian Walde (cpan:MITHALDU) <walde.christian@gmail.com>
326 haarg - Graham Knop (cpan:HAARG) <haarg@haarg.org>
330 Copyright (c) 2010 the strictures L</AUTHOR> and L</CONTRIBUTORS>
335 This library is free software and may be distributed under the same terms