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#!/usr/bin/perl

use strict;
use warnings;

use Test::More;
use Test::Exception;


{
    # test no conflicts here
    package Role::A;
    use Moose::Role;

    sub bar { 'Role::A::bar' }

    package Role::B;
    use Moose::Role;

    sub xxy { 'Role::B::xxy' }

    package Role::C;
    use Moose::Role;

    ::lives_ok {
        with qw(Role::A Role::B); # no conflict here
    } "define role C";

    sub foo { 'Role::C::foo' }
    sub zot { 'Role::C::zot' }

    package Class::A;
    use Moose;

    ::lives_ok {
        with qw(Role::C);
    } "define class A";

    sub zot { 'Class::A::zot' }
}

can_ok( Class::A->new, qw(foo bar xxy zot) );

is( Class::A->new->foo, "Role::C::foo",  "... got the right foo method" );
is( Class::A->new->zot, "Class::A::zot", "... got the right zot method" );
is( Class::A->new->bar, "Role::A::bar",  "... got the right bar method" );
is( Class::A->new->xxy, "Role::B::xxy",  "... got the right xxy method" );

{
    # check that when a role is added to another role
    # and they conflict and the method they conflict
    # with is then required.

    package Role::A::Conflict;
    use Moose::Role;

    with 'Role::A';

    sub bar { 'Role::A::Conflict::bar' }

    package Class::A::Conflict;
    use Moose;

    ::throws_ok {
        with 'Role::A::Conflict';
    }  qr/Due to a method name conflict in roles 'Role::A' and 'Role::A::Conflict', the method 'bar' must be implemented or excluded by 'Class::A::Conflict'/, '... did not fufill the requirement of &bar method';

    package Class::A::Resolved;
    use Moose;

    ::lives_ok {
        with 'Role::A::Conflict';
    } '... did fufill the requirement of &bar method';

    sub bar { 'Class::A::Resolved::bar' }
}

ok(Role::A::Conflict->meta->requires_method('bar'), '... Role::A::Conflict created the bar requirement');

can_ok( Class::A::Resolved->new, qw(bar) );

is( Class::A::Resolved->new->bar, 'Class::A::Resolved::bar', "... got the right bar method" );

{
    # check that when two roles are composed, they conflict
    # but the composing role can resolve that conflict

    package Role::D;
    use Moose::Role;

    sub foo { 'Role::D::foo' }
    sub bar { 'Role::D::bar' }

    package Role::E;
    use Moose::Role;

    sub foo { 'Role::E::foo' }
    sub xxy { 'Role::E::xxy' }

    package Role::F;
    use Moose::Role;

    ::lives_ok {
        with qw(Role::D Role::E); # conflict between 'foo's here
    } "define role Role::F";

    sub foo { 'Role::F::foo' }
    sub zot { 'Role::F::zot' }

    package Class::B;
    use Moose;

    ::lives_ok {
        with qw(Role::F);
    } "define class Class::B";

    sub zot { 'Class::B::zot' }
}

can_ok( Class::B->new, qw(foo bar xxy zot) );

is( Class::B->new->foo, "Role::F::foo",  "... got the &foo method okay" );
is( Class::B->new->zot, "Class::B::zot", "... got the &zot method okay" );
is( Class::B->new->bar, "Role::D::bar",  "... got the &bar method okay" );
is( Class::B->new->xxy, "Role::E::xxy",  "... got the &xxy method okay" );

ok(!Role::F->meta->requires_method('foo'), '... Role::F fufilled the &foo requirement');

{
    # check that a conflict can be resolved
    # by a role, but also new ones can be
    # created just as easily ...

    package Role::D::And::E::Conflict;
    use Moose::Role;

    ::lives_ok {
        with qw(Role::D Role::E); # conflict between 'foo's here
    } "... define role Role::D::And::E::Conflict";

    sub foo { 'Role::D::And::E::Conflict::foo' }  # this overrides ...

    # but these conflict
    sub xxy { 'Role::D::And::E::Conflict::xxy' }
    sub bar { 'Role::D::And::E::Conflict::bar' }

}

ok(!Role::D::And::E::Conflict->meta->requires_method('foo'), '... Role::D::And::E::Conflict fufilled the &foo requirement');
ok(Role::D::And::E::Conflict->meta->requires_method('xxy'), '... Role::D::And::E::Conflict adds the &xxy requirement');
ok(Role::D::And::E::Conflict->meta->requires_method('bar'), '... Role::D::And::E::Conflict adds the &bar requirement');

{
    # conflict propagation

    package Role::H;
    use Moose::Role;

    sub foo { 'Role::H::foo' }
    sub bar { 'Role::H::bar' }

    package Role::J;
    use Moose::Role;

    sub foo { 'Role::J::foo' }
    sub xxy { 'Role::J::xxy' }

    package Role::I;
    use Moose::Role;

    ::lives_ok {
        with qw(Role::J Role::H); # conflict between 'foo's here
    } "define role Role::I";

    sub zot { 'Role::I::zot' }
    sub zzy { 'Role::I::zzy' }

    package Class::C;
    use Moose;

    ::throws_ok {
        with qw(Role::I);
    } qr/Due to a method name conflict in roles 'Role::H' and 'Role::J', the method 'foo' must be implemented or excluded by 'Class::C'/, "defining class Class::C fails";

    sub zot { 'Class::C::zot' }

    package Class::E;
    use Moose;

    ::lives_ok {
        with qw(Role::I);
    } "resolved with method";

    sub foo { 'Class::E::foo' }
    sub zot { 'Class::E::zot' }
}

can_ok( Class::E->new, qw(foo bar xxy zot) );

is( Class::E->new->foo, "Class::E::foo", "... got the right &foo method" );
is( Class::E->new->zot, "Class::E::zot", "... got the right &zot method" );
is( Class::E->new->bar, "Role::H::bar",  "... got the right &bar method" );
is( Class::E->new->xxy, "Role::J::xxy",  "... got the right &xxy method" );

ok(Role::I->meta->requires_method('foo'), '... Role::I still have the &foo requirement');

{
    lives_ok {
        package Class::D;
        use Moose;

        has foo => ( default => __PACKAGE__ . "::foo", is => "rw" );

        sub zot { 'Class::D::zot' }

        with qw(Role::I);

    } "resolved with attr";

    can_ok( Class::D->new, qw(foo bar xxy zot) );
    is( eval { Class::D->new->bar }, "Role::H::bar", "bar" );
    is( eval { Class::D->new->zzy }, "Role::I::zzy", "zzy" );

    is( eval { Class::D->new->foo }, "Class::D::foo", "foo" );
    is( eval { Class::D->new->zot }, "Class::D::zot", "zot" );

}

done_testing;