open_closed.t

use v6;

use MONKEY-TYPING;

use Test;

plan 9;

# syn r14552

# L<S12/"Open vs Closed Classes"/"a pragma for selecting global semantics of the underlying object-oriented engine">

use oo :closed :final;

class Foo {
    method a {'called Foo.a'}
}

throws-like 'augment class Foo {method b {"called Foo.b"}}}', Exception, 'adding to closed class dies');

class Bar is open {
    method c {'called Bar.c'}
}
augment class Bar {
    method d {'called Bar.d'}
}

{
    my $o = Bar.new;
    is($o.c, 'called Bar.c', 'old method is still present');
    is($o.d, 'called Bar.d', 'new method is also present');
}

{
    # S12 gives the example of 'use class :open' as well as 'use oo :closed'
    # this seems weird to me.
    use class :open;
    class Baz {method e {'called Baz.e'}}
    augment class Baz {
        method f {'called Baz.f'}
    }

    my $o = Baz.new;
    is($o.e, 'called Baz.e', 'old method is still present');
    is($o.f, 'called Baz.f', 'new method is present as well');
}

# L<S12/"Open vs Closed Classes"/"or by lexically scoped pragma around the class definition">
# and just when you thought I ran out of generic identifiers
use class :open<Qux>;
class Qux {method g {'called Qux.g'}}
{
    augment class Qux {
        method h {'called Qux.i'}
    }
    my $o = Qux.new;
    is($o.g, 'called Qux.g', 'old is still present');
    is($o.h, 'called Qux.h', 'new method is present as well');
}

# L<S12/"Open vs Closed Classes"/"declaring individual classes closed or final">
# try a few things that come to mind to make sure it's not lurking
throws-like 'class ClosedAlpha is closed {}', Exception, '"is closed" is unimplemented');
throws-like 'class ClosedBeta  is final  {}', Exception, '"is final"  is unimplemented');

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