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#!/usr/bin/perl
use strict;
use warnings;
use Test::More tests => 23;
use Test::Exception;
use MooseX::Declare;
class BankAccount {
has 'balance' => ( isa => 'Num', is => 'rw', default => 0 );
method deposit (Num $amount) {
$self->balance( $self->balance + $amount );
}
method withdraw (Num $amount) {
my $current_balance = $self->balance();
( $current_balance >= $amount )
|| confess "Account overdrawn";
$self->balance( $current_balance - $amount );
}
}
class CheckingAccount extends BankAccount {
has 'overdraft_account' => ( isa => 'BankAccount', is => 'rw' );
before withdraw (Num $amount) {
my $overdraft_amount = $amount - $self->balance();
if ( $self->overdraft_account && $overdraft_amount > 0 ) {
$self->overdraft_account->withdraw($overdraft_amount);
$self->deposit($overdraft_amount);
}
}
}
my $savings_account = BankAccount->new(balance => 250);
isa_ok($savings_account, 'BankAccount');
is($savings_account->balance, 250, '... got the right savings balance');
lives_ok {
$savings_account->withdraw(50);
} '... withdrew from savings successfully';
is($savings_account->balance, 200, '... got the right savings balance after withdrawl');
$savings_account->deposit(150);
is($savings_account->balance, 350, '... got the right savings balance after deposit');
{
my $checking_account = CheckingAccount->new(
balance => 100,
overdraft_account => $savings_account
);
isa_ok($checking_account, 'CheckingAccount');
isa_ok($checking_account, 'BankAccount');
is($checking_account->overdraft_account, $savings_account, '... got the right overdraft account');
is($checking_account->balance, 100, '... got the right checkings balance');
lives_ok {
$checking_account->withdraw(50);
} '... withdrew from checking successfully';
is($checking_account->balance, 50, '... got the right checkings balance after withdrawl');
is($savings_account->balance, 350, '... got the right savings balance after checking withdrawl (no overdraft)');
lives_ok {
$checking_account->withdraw(200);
} '... withdrew from checking successfully';
is($checking_account->balance, 0, '... got the right checkings balance after withdrawl');
is($savings_account->balance, 200, '... got the right savings balance after overdraft withdrawl');
}
{
my $checking_account = CheckingAccount->new(
balance => 100
# no overdraft account
);
isa_ok($checking_account, 'CheckingAccount');
isa_ok($checking_account, 'BankAccount');
is($checking_account->overdraft_account, undef, '... no overdraft account');
is($checking_account->balance, 100, '... got the right checkings balance');
lives_ok {
$checking_account->withdraw(50);
} '... withdrew from checking successfully';
is($checking_account->balance, 50, '... got the right checkings balance after withdrawl');
dies_ok {
$checking_account->withdraw(200);
} '... withdrawl failed due to attempted overdraft';
is($checking_account->balance, 50, '... got the right checkings balance after withdrawl failure');
}
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