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 $VERSION;
14 my ($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
114 (with the intention of only forcing extra tests on the author side) -- or when
115 C<.git>, C<.svn>, or C<.hg> is present two directories up along with
116 C<dist.ini> (which would indicate we are in a C<dzil test> operation, via
117 L<Dist::Zilla>) -- or when the C<PERL_STRICTURES_EXTRA> environment variable is
125 use warnings FATAL => 'all';
128 no bareword::filehandles;
130 Note that C<PERL_STRICTURES_EXTRA> may at some point add even more tests, with
131 only a minor version increase, but any changes to the effect of C<use
132 strictures> in normal mode will involve a major version bump.
134 If any of the extra testing modules are not present, L<strictures> will
135 complain loudly, once, via C<warn()>, and then shut up. But you really
136 should consider installing them, they're all great anti-footgun tools.
140 I've been writing the equivalent of this module at the top of my code for
141 about a year now. I figured it was time to make it shorter.
143 Things like the importer in C<use Moose> don't help me because they turn
144 warnings on but don't make them fatal -- which from my point of view is
145 useless because I want an exception to tell me my code isn't warnings-clean.
147 Any time I see a warning from my code, that indicates a mistake.
149 Any time my code encounters a mistake, I want a crash -- not spew to STDERR
150 and then unknown (and probably undesired) subsequent behaviour.
152 I also want to ensure that obvious coding mistakes, like indirect object
153 syntax (and not so obvious mistakes that cause things to accidentally compile
154 as such) get caught, but not at the cost of an XS dependency and not at the
155 cost of blowing things up on another machine.
157 Therefore, L<strictures> turns on additional checking, but only when it thinks
158 it's running in a test file in a VCS checkout -- although if this causes
159 undesired behaviour this can be overridden by setting the
160 C<PERL_STRICTURES_EXTRA> environment variable.
162 If additional useful author side checks come to mind, I'll add them to the
163 C<PERL_STRICTURES_EXTRA> code path only -- this will result in a minor version
164 increase (e.g. 1.000000 to 1.001000 (1.1.0) or similar). Any fixes only to the
165 mechanism of this code will result in a sub-version increase (e.g. 1.000000 to
168 If the behaviour of C<use strictures> in normal mode changes in any way, that
169 will constitute a major version increase -- and the code already checks
170 when its version is tested to ensure that
174 will continue to only introduce the current set of strictures even if 2.0 is
181 This method does the setup work described above in L</DESCRIPTION>
185 This method traps the C<< strictures->VERSION(1) >> call produced by a use line
186 with a version number on it and does the version check.
188 =head1 EXTRA TESTING RATIONALE
190 Every so often, somebody complains that they're deploying via C<git pull>
191 and that they don't want L<strictures> to enable itself in this case -- and that
192 setting C<PERL_STRICTURES_EXTRA> to 0 isn't acceptable (additional ways to
193 disable extra testing would be welcome but the discussion never seems to get
196 In order to allow us to skip a couple of stages and get straight to a
197 productive conversation, here's my current rationale for turning the
198 extra testing on via a heuristic:
200 The extra testing is all stuff that only ever blows up at compile time;
201 this is intentional. So the oft-raised concern that it's different code being
202 tested is only sort of the case -- none of the modules involved affect the
203 final optree to my knowledge, so the author gets some additional compile
204 time crashes which he/she then fixes, and the rest of the testing is
205 completely valid for all environments.
207 The point of the extra testing -- especially C<no indirect> -- is to catch
208 mistakes that newbie users won't even realise are mistakes without
213 where foo is an & prototyped sub that you forgot to import -- this is
214 pernicious to track down since all I<seems> fine until it gets called
215 and you get a crash. Worse still, you can fail to have imported it due
216 to a circular require, at which point you have a load order dependent
217 bug which I've seen before now I<only> show up in production due to tiny
218 differences between the production and the development environment. I wrote
219 L<http://shadow.cat/blog/matt-s-trout/indirect-but-still-fatal/> to explain
220 this particular problem before L<strictures> itself existed.
222 As such, in my experience so far L<strictures>' extra testing has
223 I<avoided> production versus development differences, not caused them.
225 Additionally, L<strictures>' policy is very much "try and provide as much
226 protection as possible for newbies -- who won't think about whether there's
227 an option to turn on or not" -- so having only the environment variable
228 is not sufficient to achieve that (I get to explain that you need to add
229 C<use strict> at least once a week on freenode #perl -- newbies sometimes
230 completely skip steps because they don't understand that that step
233 I make no claims that the heuristic is perfect -- it's already been evolved
234 significantly over time, especially for 1.004 where we changed things to
235 ensure it only fires on files in your checkout (rather than L<strictures>-using
236 modules you happened to have installed, which was just silly). However, I
237 hope the above clarifies why a heuristic approach is not only necessary but
238 desirable from a point of view of providing new users with as much safety as
239 possible, and will allow any future discussion on the subject to focus on "how
240 do we minimise annoyance to people deploying from checkouts intentionally".
256 L<bareword::filehandles>
260 =head1 COMMUNITY AND SUPPORT
264 irc.perl.org #toolchain
266 (or bug 'mst' in query on there or freenode)
268 =head2 Git repository
270 Gitweb is on http://git.shadowcat.co.uk/ and the clone URL is:
272 git clone git://git.shadowcat.co.uk/p5sagit/strictures.git
274 The web interface to the repository is at:
276 http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=p5sagit/strictures.git
280 mst - Matt S. Trout (cpan:MSTROUT) <mst@shadowcat.co.uk>
284 Karen Etheridge (cpan:ETHER) <ether@cpan.org>
286 Mithaldu - Christian Walde (cpan:MITHALDU) <walde.christian@gmail.com>
288 haarg - Graham Knop (cpan:HAARG) <haarg@haarg.org>
292 Copyright (c) 2010 the strictures L</AUTHOR> and L</CONTRIBUTORS>
297 This library is free software and may be distributed under the same terms