X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=gitmo%2FMouse.git;a=blobdiff_plain;f=lib%2FMouse%2FMeta%2FRole.pm;h=6deb58c33e6b11120c068313ab044294a0b1e2bf;hp=6c5d32fc6cc021f1be077ec9985309cb25a462c2;hb=ea249879d28f5ce42afb95feeb7dcb6d37fcd241;hpb=3084f7a95178f560a7a973867a3b1ab4934b2932

diff --git a/lib/Mouse/Meta/Role.pm b/lib/Mouse/Meta/Role.pm
index 6c5d32f..6deb58c 100644
--- a/lib/Mouse/Meta/Role.pm
+++ b/lib/Mouse/Meta/Role.pm
@@ -1,296 +1,413 @@
 package Mouse::Meta::Role;
 use strict;
 use warnings;
-use Carp 'confess';
-use Mouse::Util qw(version authority identifier);
-
-do {
-    my %METACLASS_CACHE;
-
-    # because Mouse doesn't introspect existing classes, we're forced to
-    # only pay attention to other Mouse classes
-    sub _metaclass_cache {
-        my $class = shift;
-        my $name  = shift;
-        return $METACLASS_CACHE{$name};
-    }
 
-    sub initialize {
-        my $class = shift;
-        my $name  = shift;
-        $METACLASS_CACHE{$name} = $class->new(name => $name)
-            if !exists($METACLASS_CACHE{$name});
-        return $METACLASS_CACHE{$name};
-    }
-};
+use Mouse::Util qw(not_supported english_list);
+use Mouse::Meta::Module;
+
+use base qw(Mouse::Meta::Module);
+
+sub method_metaclass(){ 'Mouse::Meta::Role::Method' } # required for get_method()
 
-sub new {
+sub _construct_meta {
     my $class = shift;
+
     my %args  = @_;
 
+    $args{methods}          ||= {};
     $args{attributes}       ||= {};
     $args{required_methods} ||= [];
     $args{roles}            ||= [];
 
-    bless \%args, $class;
+#    return Mouse::Meta::Class->initialize($class)->new_object(%args)
+#        if $class ne __PACKAGE__;
+
+    return bless \%args, ref($class) || $class;
+}
+
+sub create_anon_role{
+    my $self = shift;
+    return $self->create(undef, @_);
+}
+
+sub is_anon_role{
+    return exists $_[0]->{anon_serial_id};
 }
 
-sub name { $_[0]->{name} }
+sub get_roles { $_[0]->{roles} }
+
+sub get_required_method_list{
+    return @{ $_[0]->{required_methods} };
+}
 
 sub add_required_methods {
-    my $self = shift;
-    my @methods = @_;
+    my($self, @methods) = @_;
     push @{$self->{required_methods}}, @methods;
 }
 
-
+sub requires_method {
+    my($self, $name) = @_;
+    return scalar( grep{ $_ eq $name } @{ $self->{required_methods} } ) != 0;
+}
 
 sub add_attribute {
     my $self = shift;
     my $name = shift;
-    my $spec = shift;
-    $self->{attributes}->{$name} = $spec;
+
+    $self->{attributes}->{$name} = (@_ == 1) ? $_[0] : { @_ };
 }
 
-sub has_attribute { exists $_[0]->{attributes}->{$_[1]}  }
-sub get_attribute_list { keys %{ $_[0]->{attributes} } }
-sub get_attribute { $_[0]->{attributes}->{$_[1]} }
+sub _canonicalize_apply_args{
+    my($self, $applicant, %args) = @_;
 
-# copied from Class::Inspector
-sub get_method_list {
-    my $self = shift;
-    my $name = $self->name;
+    if($applicant->isa('Mouse::Meta::Class')){
+        $args{_to} = 'class';
+    }
+    elsif($applicant->isa('Mouse::Meta::Role')){
+        $args{_to} = 'role';
+    }
+    else{
+        $args{_to} = 'instance';
 
-    no strict 'refs';
-    # Get all the CODE symbol table entries
-    my @functions =
-      grep !/^(?:has|with|around|before|after|augment|inner|override|super|blessed|extends|confess|excludes|meta|requires)$/,
-      grep { defined &{"${name}::$_"} }
-      keys %{"${name}::"};
-    wantarray ? @functions : \@functions;
+        not_supported 'Application::ToInstance';
+    }
+
+    if($args{alias} && !exists $args{-alias}){
+        $args{-alias} = $args{alias};
+    }
+    if($args{excludes} && !exists $args{-excludes}){
+        $args{-excludes} = $args{excludes};
+    }
+
+    if(my $excludes = $args{-excludes}){
+        $args{-excludes} = {}; # replace with a hash ref
+        if(ref $excludes){
+            %{$args{-excludes}} = (map{ $_ => undef } @{$excludes});
+        }
+        else{
+            $args{-excludes}{$excludes} = undef;
+        }
+    }
+
+    return \%args;
 }
 
-sub apply {
-    my $self  = shift;
-    my $selfname = $self->name;
-    my $class = shift;
-    my $classname = $class->name;
-    my %args  = @_;
+sub _check_required_methods{
+    my($role, $class, $args, @other_roles) = @_;
+
+    if($args->{_to} eq 'class'){
+        my $class_name = $class->name;
+        my $role_name  = $role->name;
+        my @missing;
+        foreach my $method_name(@{$role->{required_methods}}){
+            if(!$class_name->can($method_name)){
+                my $has_method      = 0;
+
+                foreach my $another_role_spec(@other_roles){
+                    my $another_role_name = $another_role_spec->[0];
+                    if($role_name ne $another_role_name && $another_role_name->can($method_name)){
+                        $has_method = 1;
+                        last;
+                    }
+                }
 
-    if ($class->isa('Mouse::Meta::Class')) {
-        for my $name (@{$self->{required_methods}}) {
-            unless ($classname->can($name)) {
-                confess "'$selfname' requires the method '$name' to be implemented by '$classname'";
+                push @missing, $method_name if !$has_method;
             }
         }
+        if(@missing){
+            $class->throw_error("'$role_name' requires the "
+                . (@missing == 1 ? 'method' : 'methods')
+                . " "
+                . english_list(map{ sprintf q{'%s'}, $_ } @missing)
+                . " to be implemented by '$class_name'");
+        }
+    }
+    elsif($args->{_to} eq 'role'){
+        # apply role($role) to role($class)
+        foreach my $method_name($role->get_required_method_list){
+            next if $class->has_method($method_name); # already has it
+            $class->add_required_methods($method_name);
+        }
     }
 
-    {
-        no strict 'refs';
-        for my $name ($self->get_method_list) {
-            next if $name eq 'meta';
-
-            my $class_function = "${classname}::${name}";
-            my $role_function = "${selfname}::${name}";
-            if (defined &$class_function) {
-                # XXX what's Moose's behavior?
-                #next;
-            } else {
-                *$class_function = *$role_function;
+    return;
+}
+
+sub _apply_methods{
+    my($role, $class, $args) = @_;
+
+    my $role_name  = $role->name;
+    my $class_name = $class->name;
+
+    my $alias    = $args->{-alias};
+    my $excludes = $args->{-excludes};
+
+    foreach my $method_name($role->get_method_list){
+        next if $method_name eq 'meta';
+
+        my $code = $role_name->can($method_name);
+
+        if(!exists $excludes->{$method_name}){
+            if(!$class->has_method($method_name)){
+                $class->add_method($method_name => $code);
             }
-            if ($args{alias} && $args{alias}->{$name}) {
-                my $dstname = $args{alias}->{$name};
-                unless ($classname->can($dstname)) {
-                    *{"${classname}::${dstname}"} = \&$role_function;
-                }
+        }
+
+        if($alias && $alias->{$method_name}){
+            my $dstname = $alias->{$method_name};
+
+            my $dstcode = do{ no strict 'refs'; *{$class_name . '::' . $dstname}{CODE} };
+
+            if(defined($dstcode) && $dstcode != $code){
+                $class->throw_error("Cannot create a method alias if a local method of the same name exists");
+            }
+            else{
+                $class->add_method($dstname => $code);
             }
         }
     }
 
-    if ($class->isa('Mouse::Meta::Class')) {
+    return;
+}
+
+sub _apply_attributes{
+    my($role, $class, $args) = @_;
+
+    if ($args->{_to} eq 'class') {
         # apply role to class
-        for my $name ($self->get_attribute_list) {
-            next if $class->has_attribute($name);
-            my $spec = $self->get_attribute($name);
-
-            my $metaclass = 'Mouse::Meta::Attribute';
-            if ( my $metaclass_name = $spec->{metaclass} ) {
-                my $new_class = Mouse::Util::resolve_metaclass_alias(
-                    'Attribute',
-                    $metaclass_name
-                );
-                if ( $metaclass ne $new_class ) {
-                    $metaclass = $new_class;
-                }
-            }
+        for my $attr_name ($role->get_attribute_list) {
+            next if $class->has_attribute($attr_name);
 
-            $metaclass->create($class, $name, %$spec);
+            my $spec = $role->get_attribute($attr_name);
+
+            $class->add_attribute($attr_name => %{$spec});
         }
-    } else {
+    }
+    elsif($args->{_to} eq 'role'){
         # apply role to role
-        # XXX Room for speed improvement
-        for my $name ($self->get_attribute_list) {
-            next if $class->has_attribute($name);
-            my $spec = $self->get_attribute($name);
-            $class->add_attribute($name, $spec);
+        for my $attr_name ($role->get_attribute_list) {
+            next if $class->has_attribute($attr_name);
+
+            my $spec = $role->get_attribute($attr_name);
+            $class->add_attribute($attr_name => $spec);
         }
     }
 
-    # XXX Room for speed improvement in role to role
-    for my $modifier_type (qw/before after around override/) {
-        my $add_method = "add_${modifier_type}_method_modifier";
-        my $modified = $self->{"${modifier_type}_method_modifiers"};
+    return;
+}
+
+sub _apply_modifiers{
+    my($role, $class, $args) = @_;
 
-        for my $method_name (keys %$modified) {
-            for my $code (@{ $modified->{$method_name} }) {
-                $class->$add_method($method_name => $code);
+    for my $modifier_type (qw/override before around after/) {
+        my $add_modifier = "add_${modifier_type}_method_modifier";
+        my $modifiers    = $role->{"${modifier_type}_method_modifiers"};
+
+        while(my($method_name, $modifier_codes) = each %{$modifiers}){
+            foreach my $code(ref($modifier_codes) eq 'ARRAY' ? @{$modifier_codes} : $modifier_codes){
+                $class->$add_modifier($method_name => $code);
             }
         }
     }
+    return;
+}
+
+sub _append_roles{
+    my($role, $class, $args) = @_;
+
+    my $roles = ($args->{_to} eq 'class') ? $class->roles : $class->get_roles;
 
-    # append roles
-    push @{ $class->roles }, $self, @{ $self->roles };
+    foreach my $r($role, @{$role->get_roles}){
+        if(!$class->does_role($r->name)){
+            push @{$roles}, $r;
+        }
+    }
+    return;
+}
+
+# Moose uses Application::ToInstance, Application::ToClass, Application::ToRole
+sub apply {
+    my $self      = shift;
+    my $applicant = shift;
+
+    my $args = $self->_canonicalize_apply_args($applicant, @_);
+
+    $self->_check_required_methods($applicant, $args);
+    $self->_apply_methods($applicant, $args);
+    $self->_apply_attributes($applicant, $args);
+    $self->_apply_modifiers($applicant, $args);
+    $self->_append_roles($applicant, $args);
+    return;
 }
 
 sub combine_apply {
     my(undef, $class, @roles) = @_;
-    my $classname = $class->name;
-
-    if ($class->isa('Mouse::Meta::Class')) {
-        for my $role_spec (@roles) {
-            my $self = $role_spec->[0]->meta;
-            for my $name (@{$self->{required_methods}}) {
-                unless ($classname->can($name)) {
-                    my $method_required = 0;
-                    for my $role (@roles) {
-                        $method_required = 1 if $self->name ne $role->[0] && $role->[0]->can($name);
-                    }
-                    confess "'".$self->name."' requires the method '$name' to be implemented by '$classname'"
-                        unless $method_required;
-                }
-            }
-        }
-    }
 
-    {
-        no strict 'refs';
-        for my $role_spec (@roles) {
-            my $self = $role_spec->[0]->meta;
-            my $selfname = $self->name;
-            my %args = %{ $role_spec->[1] };
-            for my $name ($self->get_method_list) {
-                next if $name eq 'meta';
-
-                my $class_function = "${classname}::${name}";
-                my $role_function = "${selfname}::${name}";
-                if (defined &$class_function) {
-                    # XXX what's Moose's behavior?
-                    #next;
-                } else {
-                    *$class_function = *$role_function;
-                }
-                if ($args{alias} && $args{alias}->{$name}) {
-                    my $dstname = $args{alias}->{$name};
-                    unless ($classname->can($dstname)) {
-                        *{"${classname}::${dstname}"} = \&$role_function;
-                    }
-                }
-            }
-        }
+    if($class->isa('Mouse::Object')){
+        not_supported 'Application::ToInstance';
     }
 
+    # check conflicting
+    my %method_provided;
+    my @method_conflicts;
+    my %attr_provided;
+    my %override_provided;
 
-    if ($class->isa('Mouse::Meta::Class')) {
-        # apply role to class
-        for my $role_spec (@roles) {
-            my $self = $role_spec->[0]->meta;
-            for my $name ($self->get_attribute_list) {
-                next if $class->has_attribute($name);
-                my $spec = $self->get_attribute($name);
-
-                my $metaclass = 'Mouse::Meta::Attribute';
-                if ( my $metaclass_name = $spec->{metaclass} ) {
-                    my $new_class = Mouse::Util::resolve_metaclass_alias(
-                        'Attribute',
-                        $metaclass_name
-                    );
-                    if ( $metaclass ne $new_class ) {
-                        $metaclass = $new_class;
-                    }
-                }
+    foreach my $role_spec (@roles) {
+        my $role      = $role_spec->[0]->meta;
+        my $role_name = $role->name;
+
+        # methods
+        foreach my $method_name($role->get_method_list){
+            next if $class->has_method($method_name); # manually resolved
+
+            my $code = do{ no strict 'refs'; \&{ $role_name . '::' . $method_name } };
+
+            my $c = $method_provided{$method_name};
 
-                $metaclass->create($class, $name, %$spec);
+            if($c && $c->[0] != $code){
+                push @{$c}, $role;
+                push @method_conflicts, $c;
             }
-        }
-    } else {
-        # apply role to role
-        # XXX Room for speed improvement
-        for my $role_spec (@roles) {
-            my $self = $role_spec->[0]->meta;
-            for my $name ($self->get_attribute_list) {
-                next if $class->has_attribute($name);
-                my $spec = $self->get_attribute($name);
-                $class->add_attribute($name, $spec);
+            else{
+                $method_provided{$method_name} = [$code, $method_name, $role];
             }
         }
-    }
 
-    # XXX Room for speed improvement in role to role
-    for my $modifier_type (qw/before after around override/) {
-        my $add_method = "add_${modifier_type}_method_modifier";
-        for my $role_spec (@roles) {
-            my $self = $role_spec->[0]->meta;
-            my $modified = $self->{"${modifier_type}_method_modifiers"};
+        # attributes
+        foreach my $attr_name($role->get_attribute_list){
+            my $attr = $role->get_attribute($attr_name);
+            my $c    = $attr_provided{$attr_name};
+            if($c && $c != $attr){
+                $class->throw_error("We have encountered an attribute conflict with '$attr_name' "
+                                   . "during composition. This is fatal error and cannot be disambiguated.")
+            }
+            else{
+                $attr_provided{$attr_name} = $attr;
+            }
+        }
 
-            for my $method_name (keys %$modified) {
-                for my $code (@{ $modified->{$method_name} }) {
-                    $class->$add_method($method_name => $code);
-                }
+        # override modifiers
+        foreach my $method_name($role->get_method_modifier_list('override')){
+            my $override = $role->get_override_method_modifier($method_name);
+            my $c        = $override_provided{$method_name};
+            if($c && $c != $override){
+                $class->throw_error( "We have encountered an 'override' method conflict with '$method_name' during "
+                                   . "composition (Two 'override' methods of the same name encountered). "
+                                   . "This is fatal error.")
+            }
+            else{
+                $override_provided{$method_name} = $override;
             }
         }
     }
-
-    # append roles
-    my %role_apply_cache;
-    my $apply_roles = $class->roles;
-    for my $role_spec (@roles) {
-        my $self = $role_spec->[0]->meta;
-        push @$apply_roles, $self unless $role_apply_cache{$self}++;
-        for my $role (@{ $self->roles }) {
-            push @$apply_roles, $role unless $role_apply_cache{$role}++;
+    if(@method_conflicts){
+        my $error;
+
+        if(@method_conflicts == 1){
+            my($code, $method_name, @roles) = @{$method_conflicts[0]};
+            $class->throw_error(
+                sprintf q{Due to a method name conflict in roles %s, the method '%s' must be implemented or excluded by '%s'},
+                    english_list(map{ sprintf q{'%s'}, $_->name } @roles), $method_name, $class->name
+            );
+        }
+        else{
+            @method_conflicts = sort { $a->[0] cmp $b->[0] } @method_conflicts; # to avoid hash-ordering bugs
+            my $methods = english_list(map{ sprintf q{'%s'}, $_->[1] } @method_conflicts);
+            my $roles   = english_list(
+                map{ sprintf q{'%s'}, $_->name }
+                map{ my($code, $method_name, @roles) = @{$_}; @roles } @method_conflicts
+            );
+
+            $class->throw_error(
+                sprintf q{Due to method name conflicts in roles %s, the methods %s must be implemented or excluded by '%s'},
+                    $roles, $methods, $class->name
+            );
         }
     }
+
+    foreach my $role_spec (@roles) {
+        my($role_name, $args) = @{$role_spec};
+
+        my $role = $role_name->meta;
+
+        $args = $role->_canonicalize_apply_args($class, %{$args});
+
+        $role->_check_required_methods($class, $args, @roles);
+        $role->_apply_methods($class, $args);
+        $role->_apply_attributes($class, $args);
+        $role->_apply_modifiers($class, $args);
+        $role->_append_roles($class, $args);
+    }
+    return;
 }
 
-for my $modifier_type (qw/before after around override/) {
-    no strict 'refs';
-    *{ __PACKAGE__ . '::' . "add_${modifier_type}_method_modifier" } = sub {
+for my $modifier_type (qw/before after around/) {
+
+    my $modifier = "${modifier_type}_method_modifiers";
+    my $add_method_modifier =  sub {
         my ($self, $method_name, $method) = @_;
 
-        push @{ $self->{"${modifier_type}_method_modifiers"}->{$method_name} },
-            $method;
+        push @{ $self->{$modifier}->{$method_name} ||= [] }, $method;
+        return;
     };
-
-    *{ __PACKAGE__ . '::' . "get_${modifier_type}_method_modifiers" } = sub {
-        my ($self, $method_name, $method) = @_;
-        @{ $self->{"${modifier_type}_method_modifiers"}->{$method_name} || [] }
+    my $has_method_modifiers = sub{
+        my($self, $method_name) = @_;
+        my $m = $self->{$modifier}->{$method_name};
+        return $m && @{$m} != 0;
+    };
+    my $get_method_modifiers = sub {
+        my ($self, $method_name) = @_;
+        return @{ $self->{$modifier}->{$method_name} ||= [] }
     };
+
+    no strict 'refs';
+    *{ 'add_' . $modifier_type . '_method_modifier'  } = $add_method_modifier;
+    *{ 'has_' . $modifier_type . '_method_modifiers' } = $has_method_modifiers;
+    *{ 'get_' . $modifier_type . '_method_modifiers' } = $get_method_modifiers;
 }
 
-sub roles { $_[0]->{roles} }
+sub add_override_method_modifier{
+    my($self, $method_name, $method) = @_;
 
+    if($self->has_method($method_name)){
+        # This error happens in the override keyword or during role composition,
+        # so I added a message, "A local method of ...", only for compatibility (gfx)
+        $self->throw_error("Cannot add an override of method '$method_name' "
+                   . "because there is a local version of '$method_name'"
+                   . "(A local method of the same name as been found)");
+    }
+
+    $self->{override_method_modifiers}->{$method_name} = $method;
+}
+
+sub has_override_method_modifier {
+    my ($self, $method_name) = @_;
+    return exists $self->{override_method_modifiers}->{$method_name};
+}
+
+sub get_override_method_modifier {
+    my ($self, $method_name) = @_;
+    return $self->{override_method_modifiers}->{$method_name};
+}
+
+sub get_method_modifier_list {
+    my($self, $modifier_type) = @_;
+
+    return keys %{ $self->{$modifier_type . '_method_modifiers'} };
+}
 
 # This is currently not passing all the Moose tests.
 sub does_role {
     my ($self, $role_name) = @_;
 
     (defined $role_name)
-        || confess "You must supply a role name to look for";
+        || $self->throw_error("You must supply a role name to look for");
 
     # if we are it,.. then return true
     return 1 if $role_name eq $self->name;
-
-    for my $role (@{ $self->{roles} }) {
+    # otherwise.. check our children
+    for my $role (@{ $self->get_roles }) {
         return 1 if $role->does_role($role_name);
     }
     return 0;