4 use warnings FATAL => 'all';
7 *_PERL_LT_5_8_4 = ($] < 5.008004) ? sub(){1} : sub(){0};
10 our $VERSION = '1.005005';
11 $VERSION = eval $VERSION;
14 my ($class, $version) = @_;
16 last unless defined && !ref && int != 1;
17 die "Major version specified as $_ - this is strictures version 1";
19 # passing undef here may either warn or die depending on the version of perl.
20 # we can't match the caller's warning state in this case, so just disable the
22 no warnings 'uninitialized';
23 shift->SUPER::VERSION(@_);
26 our $extra_load_states;
32 warnings->import(FATAL => 'all');
34 my $extra_tests = do {
35 if (exists $ENV{PERL_STRICTURES_EXTRA}) {
36 if (_PERL_LT_5_8_4 and $ENV{PERL_STRICTURES_EXTRA}) {
37 die 'PERL_STRICTURES_EXTRA checks are not available on perls older than 5.8.4: '
38 . "please unset \$ENV{PERL_STRICTURES_EXTRA}\n";
40 $ENV{PERL_STRICTURES_EXTRA};
41 } elsif (! _PERL_LT_5_8_4) {
42 (caller)[1] =~ /^(?:t|xt|lib|blib)[\\\/]/
43 and defined $Smells_Like_VCS ? $Smells_Like_VCS
44 : ( $Smells_Like_VCS = !!(
45 -e '.git' || -e '.svn' || -e '.hg'
46 || (-e '../../dist.ini'
47 && (-e '../../.git' || -e '../../.svn' || -e '../../.hg' ))
52 $extra_load_states ||= do {
55 foreach my $mod (qw(indirect multidimensional bareword::filehandles)) {
56 eval "require $mod; \$rv{'$mod'} = 1;" or do {
59 # courtesy of the 5.8 require bug
60 # (we do a copy because 5.16.2 at least uses the same read-only
61 # scalars for the qw() list and it doesn't seem worth a $^V check)
63 (my $file = $mod) =~ s|::|/|g;
64 delete $INC{"${file}.pm"};
69 my $failed = join ' ', @failed;
71 strictures.pm extra testing active but couldn't load all modules. Missing were:
75 Extra testing is auto-enabled in checkouts only, so if you're the author
76 of a strictures-using module you need to run:
78 cpan indirect multidimensional bareword::filehandles
80 but these modules are not required by your users.
87 indirect->unimport(':fatal') if $extra_load_states->{indirect};
88 multidimensional->unimport if $extra_load_states->{multidimensional};
89 bareword::filehandles->unimport if $extra_load_states->{'bareword::filehandles'};
98 strictures - turn on strict and make all warnings fatal
107 use warnings FATAL => 'all';
109 except when called from a file which matches:
111 (caller)[1] =~ /^(?:t|xt|lib|blib)[\\\/]/
113 and when either C<.git>, C<.svn>, or C<.hg> is present in the current directory (with
114 the intention of only forcing extra tests on the author side) -- or when C<.git>,
115 C<.svn>, or C<.hg> is present two directories up along with C<dist.ini> (which would
116 indicate we are in a C<dzil test> operation, via L<Dist::Zilla>) --
117 or when the C<PERL_STRICTURES_EXTRA> environment variable is set, in which case
124 use warnings FATAL => 'all';
127 no bareword::filehandles;
129 Note that C<PERL_STRICTURES_EXTRA> may at some point add even more tests, with only a minor
130 version increase, but any changes to the effect of C<use strictures> in
131 normal mode will involve a major version bump.
133 If any of the extra testing modules are not present, L<strictures> will
134 complain loudly, once, via C<warn()>, and then shut up. But you really
135 should consider installing them, they're all great anti-footgun tools.
139 I've been writing the equivalent of this module at the top of my code for
140 about a year now. I figured it was time to make it shorter.
142 Things like the importer in C<use Moose> don't help me because they turn
143 warnings on but don't make them fatal -- which from my point of view is
144 useless because I want an exception to tell me my code isn't warnings-clean.
146 Any time I see a warning from my code, that indicates a mistake.
148 Any time my code encounters a mistake, I want a crash -- not spew to STDERR
149 and then unknown (and probably undesired) subsequent behaviour.
151 I also want to ensure that obvious coding mistakes, like indirect object
152 syntax (and not so obvious mistakes that cause things to accidentally compile
153 as such) get caught, but not at the cost of an XS dependency and not at the
154 cost of blowing things up on another machine.
156 Therefore, L<strictures> turns on additional checking, but only when it thinks
157 it's running in a test file in a VCS checkout -- although if this causes
158 undesired behaviour this can be overridden by setting the
159 C<PERL_STRICTURES_EXTRA> environment variable.
161 If additional useful author side checks come to mind, I'll add them to the
162 C<PERL_STRICTURES_EXTRA> code path only -- this will result in a minor version increase (e.g.
163 1.000000 to 1.001000 (1.1.0) or similar). Any fixes only to the mechanism of
164 this code will result in a sub-version increase (e.g. 1.000000 to 1.000001
167 If the behaviour of C<use strictures> in normal mode changes in any way, that
168 will constitute a major version increase -- and the code already checks
169 when its version is tested to ensure that
173 will continue to only introduce the current set of strictures even if 2.0 is
180 This method does the setup work described above in L</DESCRIPTION>
184 This method traps the C<< strictures->VERSION(1) >> call produced by a use line
185 with a version number on it and does the version check.
187 =head1 EXTRA TESTING RATIONALE
189 Every so often, somebody complains that they're deploying via C<git pull>
190 and that they don't want L<strictures> to enable itself in this case -- and that
191 setting C<PERL_STRICTURES_EXTRA> to 0 isn't acceptable (additional ways to
192 disable extra testing would be welcome but the discussion never seems to get
195 In order to allow us to skip a couple of stages and get straight to a
196 productive conversation, here's my current rationale for turning the
197 extra testing on via a heuristic:
199 The extra testing is all stuff that only ever blows up at compile time;
200 this is intentional. So the oft-raised concern that it's different code being
201 tested is only sort of the case -- none of the modules involved affect the
202 final optree to my knowledge, so the author gets some additional compile
203 time crashes which he/she then fixes, and the rest of the testing is
204 completely valid for all environments.
206 The point of the extra testing -- especially C<no indirect> -- is to catch
207 mistakes that newbie users won't even realise are mistakes without
212 where foo is an & prototyped sub that you forgot to import -- this is
213 pernicious to track down since all I<seems> fine until it gets called
214 and you get a crash. Worse still, you can fail to have imported it due
215 to a circular require, at which point you have a load order dependent
216 bug which I've seen before now I<only> show up in production due to tiny
217 differences between the production and the development environment. I wrote
218 L<http://shadow.cat/blog/matt-s-trout/indirect-but-still-fatal/> to explain
219 this particular problem before L<strictures> itself existed.
221 As such, in my experience so far L<strictures>' extra testing has
222 I<avoided> production versus development differences, not caused them.
224 Additionally, L<strictures>' policy is very much "try and provide as much
225 protection as possible for newbies -- who won't think about whether there's
226 an option to turn on or not" -- so having only the environment variable
227 is not sufficient to achieve that (I get to explain that you need to add
228 C<use strict> at least once a week on freenode #perl -- newbies sometimes
229 completely skip steps because they don't understand that that step
232 I make no claims that the heuristic is perfect -- it's already been evolved
233 significantly over time, especially for 1.004 where we changed things to
234 ensure it only fires on files in your checkout (rather than L<strictures>-using
235 modules you happened to have installed, which was just silly). However, I
236 hope the above clarifies why a heuristic approach is not only necessary but
237 desirable from a point of view of providing new users with as much safety as possible,
238 and will allow any future discussion on the subject to focus on "how do we
239 minimise annoyance to people deploying from checkouts intentionally".
255 L<bareword::filehandles>
259 =head1 COMMUNITY AND SUPPORT
263 irc.perl.org #toolchain
265 (or bug 'mst' in query on there or freenode)
267 =head2 Git repository
269 Gitweb is on http://git.shadowcat.co.uk/ and the clone URL is:
271 git clone git://git.shadowcat.co.uk/p5sagit/strictures.git
273 The web interface to the repository is at:
275 http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=p5sagit/strictures.git
279 mst - Matt S. Trout (cpan:MSTROUT) <mst@shadowcat.co.uk>
283 Karen Etheridge (cpan:ETHER) <ether@cpan.org>
285 Mithaldu - Christian Walde (cpan:MITHALDU) <walde.christian@gmail.com>
287 haarg - Graham Knop (cpan:HAARG) <haarg@haarg.org>
291 Copyright (c) 2010 the strictures L</AUTHOR> and L</CONTRIBUTORS>
296 This library is free software and may be distributed under the same terms