add BUILDALL support
[gitmo/Moo.git] / lib / Role / Tiny.pm
CommitLineData
ab3370e7 1package Role::Tiny;
2
3use strictures 1;
6c74d087 4use Class::Tiny::_Utils;
ab3370e7 5
6our %INFO;
7our %APPLIED_TO;
1947330a 8our %COMPOSED;
ab3370e7 9
10sub import {
11 my $target = caller;
de3d4906 12 strictures->import;
ab3370e7 13 # get symbol table reference
14 my $stash = do { no strict 'refs'; \%{"${target}::"} };
15 # install before/after/around subs
16 foreach my $type (qw(before after around)) {
5a247406 17 *{_getglob "${target}::${type}"} = sub {
ab3370e7 18 push @{$INFO{$target}{modifiers}||=[]}, [ $type => @_ ];
19 };
20 }
5a247406 21 *{_getglob "${target}::requires"} = sub {
ab3370e7 22 push @{$INFO{$target}{requires}||=[]}, @_;
23 };
5a247406 24 *{_getglob "${target}::with"} = sub {
25 die "Only one role supported at a time by with" if @_ > 1;
26 Role::Tiny->apply_role_to_package($_[0], $target);
27 };
96d3f07a 28 *{_getglob "${target}::has"} = sub {
29 my ($name, %spec) = @_;
30 ($INFO{$target}{accessor_maker} ||= do {
31 require Method::Generate::Accessor;
32 Method::Generate::Accessor->new
33 })->generate_method($target, $name, \%spec);
34 $INFO{$target}{attributes}{$name} = \%spec;
35 };
ab3370e7 36 # grab all *non-constant* (ref eq 'SCALAR') subs present
37 # in the symbol table and store their refaddrs (no need to forcibly
38 # inflate constant subs into real subs) - also add '' to here (this
39 # is used later)
40 @{$INFO{$target}{not_methods}={}}{
41 '', map { *$_{CODE}||() } grep !(ref eq 'SCALAR'), values %$stash
42 } = ();
43 # a role does itself
44 $APPLIED_TO{$target} = { $target => undef };
45}
46
47sub apply_role_to_package {
1947330a 48 my ($me, $role, $to) = @_;
49
ab3370e7 50 die "This is apply_role_to_package" if ref($to);
1947330a 51 die "${role} is not a Role::Tiny" unless my $info = $INFO{$role};
52
53 $me->_check_requires($to, $role, @{$info->{requires}||[]});
54
55 $me->_install_methods($to, $role);
56
57 $me->_install_modifiers($to, $info->{modifiers});
58
59 # only add does() method to classes and only if they don't have one
60 if (not $INFO{$to} and not $to->can('does')) {
61 *{_getglob "${to}::does"} = \&does_role;
62 }
63
64 $me->_handle_constructor($to, $info->{attributes});
65
66 # copy our role list into the target's
67 @{$APPLIED_TO{$to}||={}}{keys %{$APPLIED_TO{$role}}} = ();
68}
69
70sub apply_roles_to_object {
71 my ($me, $object, @roles) = @_;
72 die "No roles supplied!" unless @roles;
73 my $class = ref($object);
74 bless($object, $me->create_class_with_roles($class, @roles));
75 $object;
76}
77
78sub create_class_with_roles {
79 my ($me, $superclass, @roles) = @_;
80
81 my $new_name = join('+', $superclass, my $compose_name = join '+', @roles);
82 return $new_name if $COMPOSED{class}{$new_name};
83
84 foreach my $role (@roles) {
85 die "${role} is not a Role::Tiny" unless my $info = $INFO{$role};
86 }
87
098a367b 88 require Class::Tiny::_mro;
1947330a 89 require Sub::Quote;
90
91 my @composable = map $me->_composable_package_for($_), reverse @roles;
92
93 *{_getglob("${new_name}::ISA")} = [ @composable, $superclass ];
94
95 my @info = map +($INFO{$_} ? $INFO{$_} : ()), @roles;
96
97 $me->_check_requires(
98 $new_name, $compose_name,
99 do { my %h; @h{map @{$_->{requires}||[]}, @info} = (); keys %h }
100 );
101 $me->_handle_constructor(
102 $new_name, { map %{$_->{attr_info}||{}}, @info }
103 );
104
105 *{_getglob "${new_name}::does"} = \&does_role unless $new_name->can('does');
106
107 @{$APPLIED_TO{$new_name}||={}}{
108 map keys %{$APPLIED_TO{$_}}, @roles
109 } = ();
110
111 $COMPOSED{class}{$new_name} = 1;
112 return $new_name;
113}
114
115sub _composable_package_for {
116 my ($me, $role) = @_;
117 my $composed_name = 'Role::Tiny::_COMPOSABLE::'.$role;
118 return $composed_name if $COMPOSED{role}{$composed_name};
119 $me->_install_methods($composed_name, $role);
120 my $base_name = $composed_name.'::_BASE';
121 *{_getglob("${composed_name}::ISA")} = [ $base_name ];
122 my $modifiers = $INFO{$role}{modifiers}||[];
123 foreach my $modified (
124 do { my %h; @h{map $_->[1], @$modifiers} = (); keys %h }
125 ) {
126 Sub::Quote::quote_sub(
127 "${base_name}::${modified}" => q{ shift->next::method(@_) }
128 );
129 }
130 $me->_install_modifiers($composed_name, $modifiers);
131 $COMPOSED{role}{$composed_name} = 1;
132 return $composed_name;
133}
134
135sub _check_requires {
136 my ($me, $to, $name, @requires) = @_;
137 if (my @requires_fail = grep !$to->can($_), @requires) {
138 # role -> role, add to requires, role -> class, error out
139 if (my $to_info = $INFO{$to}) {
140 push @{$to_info->{requires}||=[]}, @requires_fail;
141 } else {
142 die "Can't apply ${name} to ${to} - missing ".join(', ', @requires_fail);
143 }
144 }
145}
146
147sub _install_methods {
148 my ($me, $to, $role) = @_;
149
150 my $info = $INFO{$role};
151
ab3370e7 152 my $methods = $info->{methods} ||= do {
153 # grab role symbol table
154 my $stash = do { no strict 'refs'; \%{"${role}::"}};
155 my $not_methods = $info->{not_methods};
156 +{
157 # grab all code entries that aren't in the not_methods list
158 map {
934ea2c1 159 my $code = *{$stash->{$_}}{CODE};
160 # rely on the '' key we added in import for "no code here"
161 exists $not_methods->{$code||''} ? () : ($_ => $code)
ab3370e7 162 } grep !(ref($stash->{$_}) eq 'SCALAR'), keys %$stash
163 };
164 };
1947330a 165
ab3370e7 166 # grab target symbol table
167 my $stash = do { no strict 'refs'; \%{"${to}::"}};
1947330a 168
ab3370e7 169 # determine already extant methods of target
170 my %has_methods;
171 @has_methods{grep
172 +((ref($stash->{$_}) eq 'SCALAR') || (*{$stash->{$_}}{CODE})),
173 keys %$stash
174 } = ();
ab3370e7 175
1947330a 176 foreach my $i (grep !exists $has_methods{$_}, keys %$methods) {
ab3370e7 177 no warnings 'once';
5a247406 178 *{_getglob "${to}::${i}"} = $methods->{$i};
ab3370e7 179 }
1947330a 180}
ab3370e7 181
1947330a 182sub _install_modifiers {
183 my ($me, $to, $modifiers) = @_;
184 foreach my $modifier (@{$modifiers||[]}) {
6c74d087 185 _install_modifier($to, @{$modifier});
ab3370e7 186 }
1947330a 187}
ab3370e7 188
1947330a 189sub _handle_constructor {
190 my ($me, $to, $attr_info) = @_;
191 return unless $attr_info && keys %$attr_info;
192 if ($INFO{$to}) {
193 @{$INFO{$to}{attributes}||={}}{keys %$attr_info} = values %$attr_info;
194 } else {
195 # only fiddle with the constructor if the target is a Class::Tiny class
196 if ($INC{"Class/Tiny.pm"}
197 and my $con = Class::Tiny->_constructor_maker_for($to)) {
198 $con->register_attribute_specs(%$attr_info);
96d3f07a 199 }
200 }
ab3370e7 201}
202
203sub does_role {
204 my ($package, $role) = @_;
205 return exists $APPLIED_TO{$package}{$role};
206}
207
2081;