4 use warnings FATAL => 'all';
7 *_PERL_LT_5_8_4 = ($] < 5.008004) ? sub(){1} : sub(){0};
10 our $VERSION = '1.005005';
13 my ($class, $version) = @_;
15 last unless defined && !ref && int != 1;
16 die "Major version specified as $_ - this is strictures version 1";
18 # passing undef here may either warn or die depending on the version of perl.
19 # we can't match the caller's warning state in this case, so just disable the
21 no warnings 'uninitialized';
22 shift->SUPER::VERSION(@_);
25 our $extra_load_states;
31 warnings->import(FATAL => 'all');
33 my $extra_tests = do {
34 if (exists $ENV{PERL_STRICTURES_EXTRA}) {
35 if (_PERL_LT_5_8_4 and $ENV{PERL_STRICTURES_EXTRA}) {
36 die 'PERL_STRICTURES_EXTRA checks are not available on perls older than 5.8.4: '
37 . "please unset \$ENV{PERL_STRICTURES_EXTRA}\n";
39 $ENV{PERL_STRICTURES_EXTRA};
40 } elsif (_PERL_LT_5_8_4) {
41 (caller)[1] =~ /^(?:t|xt|lib|blib)[\\\/]/
42 and defined $Smells_Like_VCS ? $Smells_Like_VCS
43 : ( $Smells_Like_VCS = (
44 -e '.git' || -e '.svn' || -e '.hg'
45 || (-e '../../dist.ini'
46 && (-e '../../.git' || -e '../../.svn' || -e '../../.hg' ))
51 $extra_load_states ||= do {
54 foreach my $mod (qw(indirect multidimensional bareword::filehandles)) {
55 eval "require $mod; \$rv{'$mod'} = 1;" or do {
58 # courtesy of the 5.8 require bug
59 # (we do a copy because 5.16.2 at least uses the same read-only
60 # scalars for the qw() list and it doesn't seem worth a $^V check)
62 (my $file = $mod) =~ s|::|/|g;
63 delete $INC{"${file}.pm"};
68 my $failed = join ' ', @failed;
70 strictures.pm extra testing active but couldn't load all modules. Missing were:
74 Extra testing is auto-enabled in checkouts only, so if you're the author
75 of a strictures-using module you need to run:
77 cpan indirect multidimensional bareword::filehandles
79 but these modules are not required by your users.
86 indirect->unimport(':fatal') if $extra_load_states->{indirect};
87 multidimensional->unimport if $extra_load_states->{multidimensional};
88 bareword::filehandles->unimport if $extra_load_states->{'bareword::filehandles'};
97 strictures - turn on strict and make all warnings fatal
106 use warnings FATAL => 'all';
108 except when called from a file which matches:
110 (caller)[1] =~ /^(?:t|xt|lib|blib)[\\\/]/
112 and when either C<.git>, C<.svn>, or C<.hg> is present in the current directory (with
113 the intention of only forcing extra tests on the author side) -- or when C<.git>,
114 C<.svn>, or C<.hg> is present two directories up along with C<dist.ini> (which would
115 indicate we are in a C<dzil test> operation, via L<Dist::Zilla>) --
116 or when the C<PERL_STRICTURES_EXTRA> environment variable is set, in which case
123 use warnings FATAL => 'all';
126 no bareword::filehandles;
128 Note that C<PERL_STRICTURES_EXTRA> may at some point add even more tests, with only a minor
129 version increase, but any changes to the effect of C<use strictures> in
130 normal mode will involve a major version bump.
132 If any of the extra testing modules are not present, L<strictures> will
133 complain loudly, once, via C<warn()>, and then shut up. But you really
134 should consider installing them, they're all great anti-footgun tools.
138 I've been writing the equivalent of this module at the top of my code for
139 about a year now. I figured it was time to make it shorter.
141 Things like the importer in C<use Moose> don't help me because they turn
142 warnings on but don't make them fatal -- which from my point of view is
143 useless because I want an exception to tell me my code isn't warnings-clean.
145 Any time I see a warning from my code, that indicates a mistake.
147 Any time my code encounters a mistake, I want a crash -- not spew to STDERR
148 and then unknown (and probably undesired) subsequent behaviour.
150 I also want to ensure that obvious coding mistakes, like indirect object
151 syntax (and not so obvious mistakes that cause things to accidentally compile
152 as such) get caught, but not at the cost of an XS dependency and not at the
153 cost of blowing things up on another machine.
155 Therefore, L<strictures> turns on additional checking, but only when it thinks
156 it's running in a test file in a VCS checkout -- although if this causes
157 undesired behaviour this can be overridden by setting the
158 C<PERL_STRICTURES_EXTRA> environment variable.
160 If additional useful author side checks come to mind, I'll add them to the
161 C<PERL_STRICTURES_EXTRA> code path only -- this will result in a minor version increase (e.g.
162 1.000000 to 1.001000 (1.1.0) or similar). Any fixes only to the mechanism of
163 this code will result in a sub-version increase (e.g. 1.000000 to 1.000001
166 If the behaviour of C<use strictures> in normal mode changes in any way, that
167 will constitute a major version increase -- and the code already checks
168 when its version is tested to ensure that
172 will continue to only introduce the current set of strictures even if 2.0 is
179 This method does the setup work described above in L</DESCRIPTION>
183 This method traps the C<< strictures->VERSION(1) >> call produced by a use line
184 with a version number on it and does the version check.
186 =head1 EXTRA TESTING RATIONALE
188 Every so often, somebody complains that they're deploying via C<git pull>
189 and that they don't want L<strictures> to enable itself in this case -- and that
190 setting C<PERL_STRICTURES_EXTRA> to 0 isn't acceptable (additional ways to
191 disable extra testing would be welcome but the discussion never seems to get
194 In order to allow us to skip a couple of stages and get straight to a
195 productive conversation, here's my current rationale for turning the
196 extra testing on via a heuristic:
198 The extra testing is all stuff that only ever blows up at compile time;
199 this is intentional. So the oft-raised concern that it's different code being
200 tested is only sort of the case -- none of the modules involved affect the
201 final optree to my knowledge, so the author gets some additional compile
202 time crashes which he/she then fixes, and the rest of the testing is
203 completely valid for all environments.
205 The point of the extra testing -- especially C<no indirect> -- is to catch
206 mistakes that newbie users won't even realise are mistakes without
211 where foo is an & prototyped sub that you forgot to import -- this is
212 pernicious to track down since all I<seems> fine until it gets called
213 and you get a crash. Worse still, you can fail to have imported it due
214 to a circular require, at which point you have a load order dependent
215 bug which I've seen before now I<only> show up in production due to tiny
216 differences between the production and the development environment. I wrote
217 L<http://shadow.cat/blog/matt-s-trout/indirect-but-still-fatal/> to explain
218 this particular problem before L<strictures> itself existed.
220 As such, in my experience so far L<strictures>' extra testing has
221 I<avoided> production versus development differences, not caused them.
223 Additionally, L<strictures>' policy is very much "try and provide as much
224 protection as possible for newbies -- who won't think about whether there's
225 an option to turn on or not" -- so having only the environment variable
226 is not sufficient to achieve that (I get to explain that you need to add
227 C<use strict> at least once a week on freenode #perl -- newbies sometimes
228 completely skip steps because they don't understand that that step
231 I make no claims that the heuristic is perfect -- it's already been evolved
232 significantly over time, especially for 1.004 where we changed things to
233 ensure it only fires on files in your checkout (rather than L<strictures>-using
234 modules you happened to have installed, which was just silly). However, I
235 hope the above clarifies why a heuristic approach is not only necessary but
236 desirable from a point of view of providing new users with as much safety as possible,
237 and will allow any future discussion on the subject to focus on "how do we
238 minimise annoyance to people deploying from checkouts intentionally".
254 L<bareword::filehandles>
258 =head1 COMMUNITY AND SUPPORT
262 irc.perl.org #toolchain
264 (or bug 'mst' in query on there or freenode)
266 =head2 Git repository
268 Gitweb is on http://git.shadowcat.co.uk/ and the clone URL is:
270 git clone git://git.shadowcat.co.uk/p5sagit/strictures.git
272 The web interface to the repository is at:
274 http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=p5sagit/strictures.git
278 mst - Matt S. Trout (cpan:MSTROUT) <mst@shadowcat.co.uk>
282 Karen Etheridge (cpan:ETHER) <ether@cpan.org>
284 Mithaldu - Christian Walde (cpan:MITHALDU) <walde.christian@gmail.com>
286 haarg - Graham Knop (cpan:HAARG) <haarg@haarg.org>
290 Copyright (c) 2010 the strictures L</AUTHOR> and L</CONTRIBUTORS>
295 This library is free software and may be distributed under the same terms