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)) {
47 die "Major version specified as $version - not supported!";
49 $class->$method($opts);
53 my ($class, $opts) = @_;
55 warnings->import(FATAL => 'all');
57 if (_want_extra($opts->{file})) {
58 _load_extras(qw(indirect multidimensional bareword::filehandles));
59 indirect->unimport(':fatal')
60 if $extra_load_states{indirect};
61 multidimensional->unimport
62 if $extra_load_states{multidimensional};
63 bareword::filehandles->unimport
64 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};
79 and $file =~ /^(?:t|xt|lib|blib)[\\\/]/
80 and defined $Smells_Like_VCS ? $Smells_Like_VCS
81 : ( $Smells_Like_VCS = !!(
82 -e '.git' || -e '.svn' || -e '.hg'
83 || (-e '../../dist.ini'
84 && (-e '../../.git' || -e '../../.svn' || -e '../../.hg' ))
92 foreach my $mod (@extras) {
94 if exists $extra_load_states{$mod};
96 $extra_load_states{$mod} = eval "require $mod; 1;" or do {
99 #work around 5.8 require bug
100 (my $file = $mod) =~ s|::|/|g;
101 delete $INC{"${file}.pm"};
106 my $failed = join ' ', @failed;
107 my $extras = join ' ', @extras;
109 strictures.pm extra testing active but couldn't load all modules. Missing were:
113 Extra testing is auto-enabled in checkouts only, so if you're the author
114 of a strictures-using module you need to run:
118 but these modules are not required by your users.
128 strictures - turn on strict and make all warnings fatal
137 use warnings FATAL => 'all';
139 except when called from a file which matches:
141 (caller)[1] =~ /^(?:t|xt|lib|blib)[\\\/]/
143 and when either C<.git>, C<.svn>, or C<.hg> is present in the current directory
144 (with the intention of only forcing extra tests on the author side) -- or when
145 C<.git>, C<.svn>, or C<.hg> is present two directories up along with
146 C<dist.ini> (which would indicate we are in a C<dzil test> operation, via
147 L<Dist::Zilla>) -- or when the C<PERL_STRICTURES_EXTRA> environment variable is
155 use warnings FATAL => 'all';
158 no bareword::filehandles;
160 Note that C<PERL_STRICTURES_EXTRA> may at some point add even more tests, with
161 only a minor version increase, but any changes to the effect of C<use
162 strictures> in normal mode will involve a major version bump.
164 If any of the extra testing modules are not present, L<strictures> will
165 complain loudly, once, via C<warn()>, and then shut up. But you really
166 should consider installing them, they're all great anti-footgun tools.
170 I've been writing the equivalent of this module at the top of my code for
171 about a year now. I figured it was time to make it shorter.
173 Things like the importer in C<use Moose> don't help me because they turn
174 warnings on but don't make them fatal -- which from my point of view is
175 useless because I want an exception to tell me my code isn't warnings-clean.
177 Any time I see a warning from my code, that indicates a mistake.
179 Any time my code encounters a mistake, I want a crash -- not spew to STDERR
180 and then unknown (and probably undesired) subsequent behaviour.
182 I also want to ensure that obvious coding mistakes, like indirect object
183 syntax (and not so obvious mistakes that cause things to accidentally compile
184 as such) get caught, but not at the cost of an XS dependency and not at the
185 cost of blowing things up on another machine.
187 Therefore, L<strictures> turns on additional checking, but only when it thinks
188 it's running in a test file in a VCS checkout -- although if this causes
189 undesired behaviour this can be overridden by setting the
190 C<PERL_STRICTURES_EXTRA> environment variable.
192 If additional useful author side checks come to mind, I'll add them to the
193 C<PERL_STRICTURES_EXTRA> code path only -- this will result in a minor version
194 increase (e.g. 1.000000 to 1.001000 (1.1.0) or similar). Any fixes only to the
195 mechanism of this code will result in a sub-version increase (e.g. 1.000000 to
198 If the behaviour of C<use strictures> in normal mode changes in any way, that
199 will constitute a major version increase -- and the code already checks
200 when its version is tested to ensure that
204 will continue to only introduce the current set of strictures even if 2.0 is
211 This method does the setup work described above in L</DESCRIPTION>
215 This method traps the C<< strictures->VERSION(1) >> call produced by a use line
216 with a version number on it and does the version check.
218 =head1 EXTRA TESTING RATIONALE
220 Every so often, somebody complains that they're deploying via C<git pull>
221 and that they don't want L<strictures> to enable itself in this case -- and that
222 setting C<PERL_STRICTURES_EXTRA> to 0 isn't acceptable (additional ways to
223 disable extra testing would be welcome but the discussion never seems to get
226 In order to allow us to skip a couple of stages and get straight to a
227 productive conversation, here's my current rationale for turning the
228 extra testing on via a heuristic:
230 The extra testing is all stuff that only ever blows up at compile time;
231 this is intentional. So the oft-raised concern that it's different code being
232 tested is only sort of the case -- none of the modules involved affect the
233 final optree to my knowledge, so the author gets some additional compile
234 time crashes which he/she then fixes, and the rest of the testing is
235 completely valid for all environments.
237 The point of the extra testing -- especially C<no indirect> -- is to catch
238 mistakes that newbie users won't even realise are mistakes without
243 where foo is an & prototyped sub that you forgot to import -- this is
244 pernicious to track down since all I<seems> fine until it gets called
245 and you get a crash. Worse still, you can fail to have imported it due
246 to a circular require, at which point you have a load order dependent
247 bug which I've seen before now I<only> show up in production due to tiny
248 differences between the production and the development environment. I wrote
249 L<http://shadow.cat/blog/matt-s-trout/indirect-but-still-fatal/> to explain
250 this particular problem before L<strictures> itself existed.
252 As such, in my experience so far L<strictures>' extra testing has
253 I<avoided> production versus development differences, not caused them.
255 Additionally, L<strictures>' policy is very much "try and provide as much
256 protection as possible for newbies -- who won't think about whether there's
257 an option to turn on or not" -- so having only the environment variable
258 is not sufficient to achieve that (I get to explain that you need to add
259 C<use strict> at least once a week on freenode #perl -- newbies sometimes
260 completely skip steps because they don't understand that that step
263 I make no claims that the heuristic is perfect -- it's already been evolved
264 significantly over time, especially for 1.004 where we changed things to
265 ensure it only fires on files in your checkout (rather than L<strictures>-using
266 modules you happened to have installed, which was just silly). However, I
267 hope the above clarifies why a heuristic approach is not only necessary but
268 desirable from a point of view of providing new users with as much safety as
269 possible, and will allow any future discussion on the subject to focus on "how
270 do we minimise annoyance to people deploying from checkouts intentionally".
286 L<bareword::filehandles>
290 =head1 COMMUNITY AND SUPPORT
294 irc.perl.org #toolchain
296 (or bug 'mst' in query on there or freenode)
298 =head2 Git repository
300 Gitweb is on http://git.shadowcat.co.uk/ and the clone URL is:
302 git clone git://git.shadowcat.co.uk/p5sagit/strictures.git
304 The web interface to the repository is at:
306 http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=p5sagit/strictures.git
310 mst - Matt S. Trout (cpan:MSTROUT) <mst@shadowcat.co.uk>
314 Karen Etheridge (cpan:ETHER) <ether@cpan.org>
316 Mithaldu - Christian Walde (cpan:MITHALDU) <walde.christian@gmail.com>
318 haarg - Graham Knop (cpan:HAARG) <haarg@haarg.org>
322 Copyright (c) 2010 the strictures L</AUTHOR> and L</CONTRIBUTORS>
327 This library is free software and may be distributed under the same terms