Commit | Line | Data |
a2227e71 |
1 | package Mouse::Meta::Role; |
2 | use strict; |
3 | use warnings; |
74be9f76 |
4 | |
c6d8f5ca |
5 | use Mouse::Util qw(:meta not_supported english_list get_code_info); |
6d28c5cf |
6 | use Mouse::Meta::Module; |
f3bb863f |
7 | our @ISA = qw(Mouse::Meta::Module); |
a2227e71 |
8 | |
6cfa1e5e |
9 | sub method_metaclass(){ 'Mouse::Meta::Role::Method' } # required for get_method() |
10 | |
c6d8f5ca |
11 | # XXX: for backward compatibility |
12 | my %foreign = map{ $_ => undef } qw(Mouse::Role Carp Scalar::Util UNIVERSAL); |
13 | sub _code_is_mine{ |
14 | my($self, $code) = @_; |
15 | |
16 | my($package, $name) = get_code_info($code); |
17 | |
18 | return $package && !exists $foreign{$package}; |
19 | } |
20 | |
21 | |
8e64d0fa |
22 | sub _construct_meta { |
acf0f643 |
23 | my $class = shift; |
7a50b450 |
24 | |
acf0f643 |
25 | my %args = @_; |
26 | |
3a63a2e7 |
27 | $args{methods} ||= {}; |
59089ec3 |
28 | $args{attributes} ||= {}; |
29 | $args{required_methods} ||= []; |
47f36c05 |
30 | $args{roles} ||= []; |
274b6cce |
31 | |
7a50b450 |
32 | # return Mouse::Meta::Class->initialize($class)->new_object(%args) |
33 | # if $class ne __PACKAGE__; |
34 | |
8e64d0fa |
35 | return bless \%args, ref($class) || $class; |
7a50b450 |
36 | } |
37 | |
38 | sub create_anon_role{ |
39 | my $self = shift; |
40 | return $self->create(undef, @_); |
41 | } |
42 | |
43 | sub is_anon_role{ |
44 | return exists $_[0]->{anon_serial_id}; |
acf0f643 |
45 | } |
a2227e71 |
46 | |
afc73948 |
47 | sub get_roles { $_[0]->{roles} } |
48 | |
6cfa1e5e |
49 | sub get_required_method_list{ |
50 | return @{ $_[0]->{required_methods} }; |
51 | } |
afc73948 |
52 | |
59089ec3 |
53 | sub add_required_methods { |
ea249879 |
54 | my($self, @methods) = @_; |
59089ec3 |
55 | push @{$self->{required_methods}}, @methods; |
56 | } |
57 | |
6cfa1e5e |
58 | sub requires_method { |
59 | my($self, $name) = @_; |
60 | return scalar( grep{ $_ eq $name } @{ $self->{required_methods} } ) != 0; |
61 | } |
62 | |
274b6cce |
63 | sub add_attribute { |
64 | my $self = shift; |
65 | my $name = shift; |
6cfa1e5e |
66 | |
67 | $self->{attributes}->{$name} = (@_ == 1) ? $_[0] : { @_ }; |
da0c885d |
68 | } |
69 | |
7a50b450 |
70 | sub _canonicalize_apply_args{ |
71 | my($self, $applicant, %args) = @_; |
72 | |
73 | if($applicant->isa('Mouse::Meta::Class')){ |
74 | $args{_to} = 'class'; |
75 | } |
76 | elsif($applicant->isa('Mouse::Meta::Role')){ |
77 | $args{_to} = 'role'; |
78 | } |
79 | else{ |
80 | $args{_to} = 'instance'; |
81 | |
82 | not_supported 'Application::ToInstance'; |
83 | } |
84 | |
85 | if($args{alias} && !exists $args{-alias}){ |
86 | $args{-alias} = $args{alias}; |
87 | } |
88 | if($args{excludes} && !exists $args{-excludes}){ |
89 | $args{-excludes} = $args{excludes}; |
90 | } |
91 | |
92 | if(my $excludes = $args{-excludes}){ |
93 | $args{-excludes} = {}; # replace with a hash ref |
94 | if(ref $excludes){ |
95 | %{$args{-excludes}} = (map{ $_ => undef } @{$excludes}); |
96 | } |
97 | else{ |
98 | $args{-excludes}{$excludes} = undef; |
99 | } |
100 | } |
101 | |
102 | return \%args; |
103 | } |
104 | |
3a63a2e7 |
105 | sub _check_required_methods{ |
106 | my($role, $class, $args, @other_roles) = @_; |
107 | |
7a50b450 |
108 | if($args->{_to} eq 'class'){ |
3a63a2e7 |
109 | my $class_name = $class->name; |
7a50b450 |
110 | my $role_name = $role->name; |
111 | my @missing; |
3a63a2e7 |
112 | foreach my $method_name(@{$role->{required_methods}}){ |
7a50b450 |
113 | if(!$class_name->can($method_name)){ |
3a63a2e7 |
114 | my $has_method = 0; |
115 | |
116 | foreach my $another_role_spec(@other_roles){ |
117 | my $another_role_name = $another_role_spec->[0]; |
118 | if($role_name ne $another_role_name && $another_role_name->can($method_name)){ |
119 | $has_method = 1; |
120 | last; |
121 | } |
122 | } |
7a50b450 |
123 | |
124 | push @missing, $method_name if !$has_method; |
3a63a2e7 |
125 | } |
126 | } |
7a50b450 |
127 | if(@missing){ |
128 | $class->throw_error("'$role_name' requires the " |
129 | . (@missing == 1 ? 'method' : 'methods') |
130 | . " " |
131 | . english_list(map{ sprintf q{'%s'}, $_ } @missing) |
132 | . " to be implemented by '$class_name'"); |
133 | } |
134 | } |
135 | elsif($args->{_to} eq 'role'){ |
136 | # apply role($role) to role($class) |
137 | foreach my $method_name($role->get_required_method_list){ |
138 | next if $class->has_method($method_name); # already has it |
139 | $class->add_required_methods($method_name); |
140 | } |
3a63a2e7 |
141 | } |
2e92bb89 |
142 | |
3a63a2e7 |
143 | return; |
2e92bb89 |
144 | } |
145 | |
3a63a2e7 |
146 | sub _apply_methods{ |
147 | my($role, $class, $args) = @_; |
da0c885d |
148 | |
3a63a2e7 |
149 | my $role_name = $role->name; |
150 | my $class_name = $class->name; |
6cfa1e5e |
151 | |
7a50b450 |
152 | my $alias = $args->{-alias}; |
153 | my $excludes = $args->{-excludes}; |
e0b163e1 |
154 | |
3a63a2e7 |
155 | foreach my $method_name($role->get_method_list){ |
156 | next if $method_name eq 'meta'; |
157 | |
158 | my $code = $role_name->can($method_name); |
6cfa1e5e |
159 | |
7a50b450 |
160 | if(!exists $excludes->{$method_name}){ |
6cfa1e5e |
161 | if(!$class->has_method($method_name)){ |
162 | $class->add_method($method_name => $code); |
163 | } |
2e92bb89 |
164 | } |
2e92bb89 |
165 | |
3a63a2e7 |
166 | if($alias && $alias->{$method_name}){ |
167 | my $dstname = $alias->{$method_name}; |
6cfa1e5e |
168 | |
7a50b450 |
169 | my $dstcode = do{ no strict 'refs'; *{$class_name . '::' . $dstname}{CODE} }; |
170 | |
171 | if(defined($dstcode) && $dstcode != $code){ |
6cfa1e5e |
172 | $class->throw_error("Cannot create a method alias if a local method of the same name exists"); |
21498b08 |
173 | } |
3a63a2e7 |
174 | else{ |
175 | $class->add_method($dstname => $code); |
2e92bb89 |
176 | } |
59089ec3 |
177 | } |
178 | } |
179 | |
3a63a2e7 |
180 | return; |
181 | } |
182 | |
183 | sub _apply_attributes{ |
184 | my($role, $class, $args) = @_; |
185 | |
7a50b450 |
186 | if ($args->{_to} eq 'class') { |
b1b81553 |
187 | # apply role to class |
3a63a2e7 |
188 | for my $attr_name ($role->get_attribute_list) { |
189 | next if $class->has_attribute($attr_name); |
190 | |
191 | my $spec = $role->get_attribute($attr_name); |
05b9dc92 |
192 | |
1b9e472d |
193 | $class->add_attribute($attr_name => %{$spec}); |
b1b81553 |
194 | } |
7a50b450 |
195 | } |
196 | elsif($args->{_to} eq 'role'){ |
b1b81553 |
197 | # apply role to role |
3a63a2e7 |
198 | for my $attr_name ($role->get_attribute_list) { |
199 | next if $class->has_attribute($attr_name); |
200 | |
201 | my $spec = $role->get_attribute($attr_name); |
202 | $class->add_attribute($attr_name => $spec); |
b1b81553 |
203 | } |
da0c885d |
204 | } |
d99db7b6 |
205 | |
3a63a2e7 |
206 | return; |
207 | } |
208 | |
209 | sub _apply_modifiers{ |
210 | my($role, $class, $args) = @_; |
211 | |
7a50b450 |
212 | for my $modifier_type (qw/override before around after/) { |
3a63a2e7 |
213 | my $add_modifier = "add_${modifier_type}_method_modifier"; |
214 | my $modifiers = $role->{"${modifier_type}_method_modifiers"}; |
d99db7b6 |
215 | |
3a63a2e7 |
216 | while(my($method_name, $modifier_codes) = each %{$modifiers}){ |
6cfa1e5e |
217 | foreach my $code(ref($modifier_codes) eq 'ARRAY' ? @{$modifier_codes} : $modifier_codes){ |
3a63a2e7 |
218 | $class->$add_modifier($method_name => $code); |
d99db7b6 |
219 | } |
220 | } |
221 | } |
3a63a2e7 |
222 | return; |
da0c885d |
223 | } |
0fc8adbc |
224 | |
3a63a2e7 |
225 | sub _append_roles{ |
226 | my($role, $class, $args) = @_; |
21498b08 |
227 | |
7a50b450 |
228 | my $roles = ($args->{_to} eq 'class') ? $class->roles : $class->get_roles; |
3a63a2e7 |
229 | |
230 | foreach my $r($role, @{$role->get_roles}){ |
231 | if(!$class->does_role($r->name)){ |
232 | push @{$roles}, $r; |
21498b08 |
233 | } |
234 | } |
3a63a2e7 |
235 | return; |
236 | } |
21498b08 |
237 | |
3a63a2e7 |
238 | # Moose uses Application::ToInstance, Application::ToClass, Application::ToRole |
239 | sub apply { |
7a50b450 |
240 | my $self = shift; |
241 | my $applicant = shift; |
3a63a2e7 |
242 | |
7a50b450 |
243 | my $args = $self->_canonicalize_apply_args($applicant, @_); |
21498b08 |
244 | |
7a50b450 |
245 | $self->_check_required_methods($applicant, $args); |
246 | $self->_apply_methods($applicant, $args); |
247 | $self->_apply_attributes($applicant, $args); |
248 | $self->_apply_modifiers($applicant, $args); |
249 | $self->_append_roles($applicant, $args); |
3a63a2e7 |
250 | return; |
251 | } |
21498b08 |
252 | |
3a63a2e7 |
253 | sub combine_apply { |
254 | my(undef, $class, @roles) = @_; |
05b9dc92 |
255 | |
7a50b450 |
256 | if($class->isa('Mouse::Object')){ |
257 | not_supported 'Application::ToInstance'; |
258 | } |
259 | |
60b5c3be |
260 | # check conflicting |
261 | my %method_provided; |
262 | my @method_conflicts; |
263 | my %attr_provided; |
264 | my %override_provided; |
265 | |
266 | foreach my $role_spec (@roles) { |
267 | my $role = $role_spec->[0]->meta; |
268 | my $role_name = $role->name; |
269 | |
270 | # methods |
271 | foreach my $method_name($role->get_method_list){ |
272 | next if $class->has_method($method_name); # manually resolved |
273 | |
274 | my $code = do{ no strict 'refs'; \&{ $role_name . '::' . $method_name } }; |
275 | |
276 | my $c = $method_provided{$method_name}; |
277 | |
278 | if($c && $c->[0] != $code){ |
279 | push @{$c}, $role; |
280 | push @method_conflicts, $c; |
281 | } |
282 | else{ |
283 | $method_provided{$method_name} = [$code, $method_name, $role]; |
284 | } |
285 | } |
286 | |
287 | # attributes |
288 | foreach my $attr_name($role->get_attribute_list){ |
289 | my $attr = $role->get_attribute($attr_name); |
290 | my $c = $attr_provided{$attr_name}; |
291 | if($c && $c != $attr){ |
8e64d0fa |
292 | $class->throw_error("We have encountered an attribute conflict with '$attr_name' " |
60b5c3be |
293 | . "during composition. This is fatal error and cannot be disambiguated.") |
294 | } |
295 | else{ |
296 | $attr_provided{$attr_name} = $attr; |
297 | } |
298 | } |
299 | |
300 | # override modifiers |
301 | foreach my $method_name($role->get_method_modifier_list('override')){ |
302 | my $override = $role->get_override_method_modifier($method_name); |
303 | my $c = $override_provided{$method_name}; |
304 | if($c && $c != $override){ |
8e64d0fa |
305 | $class->throw_error( "We have encountered an 'override' method conflict with '$method_name' during " |
306 | . "composition (Two 'override' methods of the same name encountered). " |
60b5c3be |
307 | . "This is fatal error.") |
308 | } |
309 | else{ |
310 | $override_provided{$method_name} = $override; |
311 | } |
312 | } |
313 | } |
314 | if(@method_conflicts){ |
315 | my $error; |
316 | |
317 | if(@method_conflicts == 1){ |
318 | my($code, $method_name, @roles) = @{$method_conflicts[0]}; |
319 | $class->throw_error( |
320 | sprintf q{Due to a method name conflict in roles %s, the method '%s' must be implemented or excluded by '%s'}, |
321 | english_list(map{ sprintf q{'%s'}, $_->name } @roles), $method_name, $class->name |
322 | ); |
323 | } |
324 | else{ |
325 | @method_conflicts = sort { $a->[0] cmp $b->[0] } @method_conflicts; # to avoid hash-ordering bugs |
326 | my $methods = english_list(map{ sprintf q{'%s'}, $_->[1] } @method_conflicts); |
327 | my $roles = english_list( |
328 | map{ sprintf q{'%s'}, $_->name } |
329 | map{ my($code, $method_name, @roles) = @{$_}; @roles } @method_conflicts |
330 | ); |
331 | |
332 | $class->throw_error( |
333 | sprintf q{Due to method name conflicts in roles %s, the methods %s must be implemented or excluded by '%s'}, |
334 | $roles, $methods, $class->name |
335 | ); |
336 | } |
337 | } |
338 | |
3a63a2e7 |
339 | foreach my $role_spec (@roles) { |
340 | my($role_name, $args) = @{$role_spec}; |
21498b08 |
341 | |
3a63a2e7 |
342 | my $role = $role_name->meta; |
21498b08 |
343 | |
7a50b450 |
344 | $args = $role->_canonicalize_apply_args($class, %{$args}); |
345 | |
3a63a2e7 |
346 | $role->_check_required_methods($class, $args, @roles); |
347 | $role->_apply_methods($class, $args); |
348 | $role->_apply_attributes($class, $args); |
349 | $role->_apply_modifiers($class, $args); |
350 | $role->_append_roles($class, $args); |
21498b08 |
351 | } |
3a63a2e7 |
352 | return; |
21498b08 |
353 | } |
354 | |
6cfa1e5e |
355 | for my $modifier_type (qw/before after around/) { |
3a63a2e7 |
356 | |
357 | my $modifier = "${modifier_type}_method_modifiers"; |
358 | my $add_method_modifier = sub { |
fc0e0bbd |
359 | my ($self, $method_name, $method) = @_; |
360 | |
3a63a2e7 |
361 | push @{ $self->{$modifier}->{$method_name} ||= [] }, $method; |
362 | return; |
fc0e0bbd |
363 | }; |
3370794f |
364 | my $has_method_modifiers = sub{ |
365 | my($self, $method_name) = @_; |
366 | my $m = $self->{$modifier}->{$method_name}; |
367 | return $m && @{$m} != 0; |
368 | }; |
3a63a2e7 |
369 | my $get_method_modifiers = sub { |
370 | my ($self, $method_name) = @_; |
371 | return @{ $self->{$modifier}->{$method_name} ||= [] } |
c2f128e7 |
372 | }; |
c2f128e7 |
373 | |
3a63a2e7 |
374 | no strict 'refs'; |
375 | *{ 'add_' . $modifier_type . '_method_modifier' } = $add_method_modifier; |
3370794f |
376 | *{ 'has_' . $modifier_type . '_method_modifiers' } = $has_method_modifiers; |
3a63a2e7 |
377 | *{ 'get_' . $modifier_type . '_method_modifiers' } = $get_method_modifiers; |
378 | } |
47f36c05 |
379 | |
6cfa1e5e |
380 | sub add_override_method_modifier{ |
381 | my($self, $method_name, $method) = @_; |
382 | |
60b5c3be |
383 | if($self->has_method($method_name)){ |
384 | # This error happens in the override keyword or during role composition, |
385 | # so I added a message, "A local method of ...", only for compatibility (gfx) |
8e64d0fa |
386 | $self->throw_error("Cannot add an override of method '$method_name' " |
60b5c3be |
387 | . "because there is a local version of '$method_name'" |
388 | . "(A local method of the same name as been found)"); |
389 | } |
6cfa1e5e |
390 | |
391 | $self->{override_method_modifiers}->{$method_name} = $method; |
392 | } |
393 | |
8e64d0fa |
394 | sub has_override_method_modifier { |
395 | my ($self, $method_name) = @_; |
396 | return exists $self->{override_method_modifiers}->{$method_name}; |
397 | } |
398 | |
399 | sub get_override_method_modifier { |
400 | my ($self, $method_name) = @_; |
401 | return $self->{override_method_modifiers}->{$method_name}; |
6cfa1e5e |
402 | } |
403 | |
404 | sub get_method_modifier_list { |
405 | my($self, $modifier_type) = @_; |
406 | |
407 | return keys %{ $self->{$modifier_type . '_method_modifiers'} }; |
408 | } |
409 | |
67199842 |
410 | # This is currently not passing all the Moose tests. |
411 | sub does_role { |
412 | my ($self, $role_name) = @_; |
413 | |
414 | (defined $role_name) |
fce211ae |
415 | || $self->throw_error("You must supply a role name to look for"); |
67199842 |
416 | |
417 | # if we are it,.. then return true |
418 | return 1 if $role_name eq $self->name; |
3a63a2e7 |
419 | # otherwise.. check our children |
420 | for my $role (@{ $self->get_roles }) { |
67199842 |
421 | return 1 if $role->does_role($role_name); |
422 | } |
423 | return 0; |
424 | } |
425 | |
426 | |
a2227e71 |
427 | 1; |
428 | |
1820fffe |
429 | __END__ |
430 | |
431 | =head1 NAME |
432 | |
433 | Mouse::Meta::Role - The Mouse Role metaclass |
434 | |
435 | =head1 SEE ALSO |
436 | |
437 | L<Moose::Meta::Role> |
438 | |
439 | =cut |