package Test2::Compare::Custom;
use strict;
use warnings;

use base 'Test2::Compare::Base';

our $VERSION = '0.000159';

use Test2::Util::HashBase qw/code name operator stringify_got/;

use Carp qw/croak/;

sub init {
    my $self = shift;

    croak "'code' is required" unless $self->{+CODE};

    $self->{+OPERATOR} ||= 'CODE(...)';
    $self->{+NAME}     ||= '<Custom Code>';
    $self->{+STRINGIFY_GOT} = $self->SUPER::stringify_got()
      unless defined $self->{+STRINGIFY_GOT};

    $self->SUPER::init();
}

sub verify {
    my $self = shift;
    my %params = @_;
    my ($got, $exists) = @params{qw/got exists/};

    my $code = $self->{+CODE};

    local $_ = $got;
    my $ok = $code->(
        got      => $got,
        exists   => $exists,
        operator => $self->{+OPERATOR},
        name     => $self->{+NAME},
    );

    return $ok;
}

1;

__END__

=pod

=encoding UTF-8

=head1 NAME

Test2::Compare::Custom - Custom field check for comparisons.

=head1 DESCRIPTION

Sometimes you want to do something complicated or unusual when validating a
field nested inside a deep data structure. You could pull it out of the
structure and test it separately, or you can use this to embed the check. This
provides a way for you to write custom checks for fields in deep comparisons.

=head1 SYNOPSIS

    my $cus = Test2::Compare::Custom->new(
        name => 'IsRef',
        operator => 'ref(...)',
        stringify_got => 1,
        code => sub {
            my %args = @_;
            return $args{got} ? 1 : 0;
        },
    );

    # Pass
    is(
        { a => 1, ref => {},   b => 2 },
        { a => 1, ref => $cus, b => 2 },
        "This will pass"
    );

    # Fail
    is(
        {a => 1, ref => 'notref', b => 2},
        {a => 1, ref => $cus,     b => 2},
        "This will fail"
    );

=head1 ARGUMENTS

Your custom sub will be passed 4 arguments in a hash:

    code => sub {
        my %args = @_;
        # provides got, exists, operator, name
        return ref($args{got}) ? 1 : 0;
    },

C<$_> is also localized to C<got> to make it easier for those who need to use
regexes.

=over 4

=item got

=item $_

The value to be checked.

=item exists

This will be a boolean. This will be true if C<got> exists at all. If
C<exists> is false then it means C<got> is not simply undef, but doesn't
exist at all (think checking the value of a hash key that does not exist).

=item operator

The operator specified at construction.

=item name

The name provided at construction.

=back

=head1 METHODS

=over 4

=item $code = $cus->code

Returns the coderef provided at construction.

=item $name = $cus->name

Returns the name provided at construction.

=item $op = $cus->operator

Returns the operator provided at construction.

=item $stringify = $cus->stringify_got

Returns the stringify_got flag provided at construction.

=item $bool = $cus->verify(got => $got, exists => $bool)

=back

=head1 SOURCE

The source code repository for Test2-Suite can be found at
F<https://github.com/Test-More/Test2-Suite/>.

=head1 MAINTAINERS

=over 4

=item Chad Granum E<lt>exodist@cpan.orgE<gt>

=back

=head1 AUTHORS

=over 4

=item Chad Granum E<lt>exodist@cpan.orgE<gt>

=item Daniel Böhmer E<lt>dboehmer@cpan.orgE<gt>

=back

=head1 COPYRIGHT

Copyright 2018 Chad Granum E<lt>exodist@cpan.orgE<gt>.

This program is free software; you can redistribute it and/or
modify it under the same terms as Perl itself.

See F<http://dev.perl.org/licenses/>

=cut
