Question

鉴于以下角色：

package MyRole;
use Moo::Role;

sub foo { 
    return 'blah';
}

以下消费类：

package MyClass;
use Moo;
with 'MyRole';

around foo = sub { 
    my ($orig, $self) = @_;
    return 'bak' if $self->$orig eq 'baz';
    return $self->$orig;
}

我想测试around修饰符中定义的行为。我该怎么做呢？ Test :: MockModule似乎无法工作：

use MyClass;
use Test::Most;
use Test::MockModule;

my $mock = Test::MockModule->new('MyRole');
$mock->mock('foo' => sub { return 'baz' });

my $obj = MyClass->new;
# Does not work
is $obj->foo, 'bak', 'Foo is what it oughtta be';

编辑：我想要测试的是MyClass与MyRole的交互，如around修饰符中所定义。我想测试around修饰符中的代码是否符合我的想法。这是另一个与我的实际代码更接近的例子：

package MyRole2
use Moo::Role;

sub call {
    my $self = shift;
    # Connect to server, retrieve a document
    my $document = $self->get_document;
    return $document;
}

package MyClass2;
use Moo;
with 'MyRole2';

around call = sub { 
    my ($orig, $self) = @_;
    my $document = $self->$orig;
    if (has_error($document)) {
        die 'Error';
    }
    return parse($document);
};

所以我想在这里做的是模拟MyRole2::call以返回一个静态文档，该文档在我的测试装置中定义，包含错误并测试异常是否被正确抛出。我知道如何使用Test::More::throws_ok或类似方法对其进行测试。我不知道该怎么做是模拟 MyRole2 :: call 和不 MyClass2::call。

Answer 1

来自#moose上的mst：

datetime

诀窍是在之前覆盖MyRole :: foo 任何使用它的东西都会被加载。这意味着使用use 5.016; use Test::Most tests => 1; require MyRole; our $orig = MyRole->can('foo'); no warnings 'redefine'; *MyRole::foo = sub { goto &$orig }; { local $orig = sub {'baz'}; require MyClass; my $obj = MyClass->new; is $obj->foo, 'bak', 'Foo is what it oughtta be'; }代替require MyClass，因为use MyClass会转换为use MyClass，它会在之前覆盖之前的所有内容，而加载。

Answer 2

可以使用Test::MockModule

完成

这些是所需的微小变化：

around foo {应写为around foo => sub {，因为around需要子程序参考。
$self->$orig需要写为$self->($orig)
文档将其列为my ($orig, $self) = @_;，因此我将其更改为$orig->($self);

这是一个工作版本：

<强> MyRole.pm

package MyRole;
use Moo::Role;

sub foo { 
    return 'foo blah';
}

sub bar { 
    return 'bar blah';
}

1;

<强> MyClass.pm

package MyClass;

use Moo;
with 'MyRole';

around foo => sub { 
    my ($orig, $self) = (@_);
    my ($result) = $orig->($self);
    return 'bak' if $result eq 'baz'; # Will never return 'bak' as coded.
    return $result;
};

<强> test.t

#!/usr/bin/env perl

use MyClass;
use Test::Most;
use Test::MockModule;

my $obj = MyClass->new;
# foo has an around block, bar does not
is($obj->bar, 'bar blah', 'bar() returns [ bar blah ]');
is($obj->foo, 'foo blah', 'foo() returns [ foo blah ]');

my $mock = Test::MockModule->new('MyClass');
$mock->mock('foo' => sub { return 'mocked foo blah' } );

my $mocked = MyClass->new;
is($mocked->bar, 'bar blah', 'bar() still returns [ bar blah ]');
is($mocked->foo, 'mocked foo blah', 'foo() now returns mocked answer [ mocked foo blah ]');

运行

prove -v test.t
test.t .. 
ok 1 - bar() returns [ bar blah ]
ok 2 - foo() returns [ foo blah ]
ok 3 - bar() still returns [ bar blah ]
ok 4 - foo() now returns mocked answer [ mocked foo blah ]
1..4
ok
All tests successful.
Files=1, Tests=4,  0 wallclock secs ( 0.06 usr  0.01 sys +  0.19 cusr  0.00 csys =  0.26 CPU)
Result: PASS

请看一下：

Class::Method::Modifiers::around()

如何模拟Moo角色中定义的方法？

2 个答案: