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NAME

Test::Mock::One - Mock the world with one object

VERSION

version 0.011

SYNOPSIS

    use Test::Mock::One;

    my $mock = Test::Mock::One->new(
        foo      => 'return value',
        bar      => 1,

        hashref  => \{ foo => 'bar' },
        arrayref => \[ foo => 'bar' ],
        code     => sub    { return your_special_function() },

    );

    $mock->foo;         # 'return value'
    $mock->bar;         # 1
    $mock->hashref;     # { foo => bar}
    $mock->arrayref;    # [ foo, bar ]
    $mock->code;        # executes your_special_function

    $mock->no->yes->work->it; # works fine

In combination with Sub::Override:

    my $override = Sub::Override->new('Foo::Bar::baz', sub { Test::Mock::One(foo => 'bar') });

DESCRIPTION

Be able to mock many things with little code by using AUTOLOAD.

The problem this module tries to solve is to allow testing many things without having to write many lines of code. If you want to create mock objects you often need to write code like this:

    {
        no warnings qw(redefine once);
        local *Foo::thing = sub {
            return bless({}, 'Baz');
        };
        local *Baz::foo = sub { return 1 };
        local *Baz::bar = sub { return 1 };
        local *Baz::baz = sub { return 1 };
        use warnings;

        # Actual test here
    }

Test::Mock::One allows you to write a simple object that allows you to do the same with

    my $mock = Test::Mock::One->new(foo => 1, bar => 1, baz => 1);
    # Sub::Override helps too
    my $override = Sub::Override->new('Foo::thing' => sub { return $mock });

    # Actual test here

You don't actually need to define anything, by default method on a Test::Mock::One object will return itself. You can tweak the behaviour by how you instantiate the object. There are several attributes that control the object, these are defined as X-Mock attributes, see "METHODS" in Test::Mock::One for more on this.

Example

Let's say you want to test a function that retrieves a user from a database and checks if it is active

    Package Foo;
    use Moose;

    has schema => (is => 'ro');

    sub check_user_in_db {
        my ($self, $username) = @_;
        my $user = $self->schema->resultset('User')->search_rs(
            { username => $username }
        )->first;

        return $user if $user && $user->is_active;
        die "Unable to find user";
    }

    # In your test
    my $foo = Foo->new(
        schema => Test::Mock::One->new(
            schema => {
                resultset =>
                    { search_rs => { first => { is_active => undef } } }
            },
            'X-Mock-Strict' => 1,
        )
    );

    # Is the same as above, without Strict mode
    $foo = Foo->new(
        schema => Test::Mock::One->new(
            is_active => undef
            # This doesn't work with X-Mock-Strict enabled, because
            # the chain schema->resultset->search_rs->first cannot be
            # resolved
        )
    );

    throws_ok(
        sub {
            $foo->check_user_in_db('username');
        },
        qr/Unable to find user/,
        "username isn't active"
    );

    # A sunny day scenario would have been:
    my $mock = Foo->new(schema => Test::Mock::One->new());
    lives_ok(sub { $mock->check_user_in_db('username') },
        "We found the user");

METHODS

new

Instantiate a new Test::Mock::One object

X-Mock-Strict

Boolean value. Undefined attributes/methods will not be mocked and calling them makes us die.

X-Mock-ISA

Mock the ISA into the given class. Supported ways to mock the ISA:

    'X-Mock-ISA' => 'Some::Pkg',
    'X-Mock-ISA' => qr/Some::Pkg/,
    'X-Mock-ISA' => [qw(Some::Pkg Other::Pkg)],
    'X-Mock-ISA' => sub { return 0 },
    'X-Mock-ISA' => undef,
X-Mock-Stringify

Tell us how to stringify the object

    'X-Mock-Stringify' => 'My custom string',
    'X-Mock-Stringify' => sub { return "foo" },
X-Mock-Called

Boolean value. Allows mock object to keep caller information. See also Test::Mock::Two.

X-Mock-SelfArg

Boolean value. Make all the code blocks use $self. This allows you to do things like

    Test::Mock::One->new(
        'X-Mock-SelfArg' => 1,
        code             => sub {
            my $self = shift;
            die "We have bar" if $self->foo eq 'bar';
            return "some value";
        }
    );

This also impacts X-Mock-ISA and X-Mock-Stringify.

isa

Returns true or false, depending on how X-Mock-ISA is set.

can

Returns true or false, depending on how X-Mock-Strict is set.

SEE ALSO

Test::Mock::Two
Sub::Override

AUTHOR

Wesley Schwengle <waterkip@cpan.org>

COPYRIGHT AND LICENSE

This software is Copyright (c) 2017 by Wesley Schwengle.

This is free software, licensed under:

  The (three-clause) BSD License