Provided by: libtest2-suite-perl_0.000159-1_all 
NAME
Test2::Mock - Module for managing mocked classes and instances.
DESCRIPTION
This module lets you add and override methods for any package temporarily. When the instance is destroyed
it will restore the package to its original state.
SYNOPSIS
use Test2::Mock;
use MyClass;
my $mock = Test2::Mock->new(
track => $BOOL, # enable call tracking if desired
class => 'MyClass',
override => [
name => sub { 'fred' },
...
],
add => [
is_mocked => sub { 1 }
...
],
...
);
# Unmock the 'name' sub
$mock->restore('name');
...
$mock = undef; # Will remove all the mocking
CONSTRUCTION
METHODS
$mock = Test2::Mock->new(class => $CLASS, ...)
This will create a new instance of Test2::Mock that manages mocking for the specified $CLASS.
Any "Test2::Mock" method can be used as a constructor argument, each should be followed by an
arrayref of arguments to be used within the method. For instance the "add()" method:
my $mock = Test2::Mock->new(
class => 'AClass',
add => [foo => sub { 'foo' }],
);
is identical to this:
my $mock = Test2::Mock->new(
class => 'AClass',
);
$mock->add(foo => sub { 'foo' });
$mock->track($bool)
Turn tracking on or off. Any sub added/overridden/set when tracking is on will log every call in a
hash retrievable via "$mock->tracking". Changing the tracking toggle will not affect subs already
altered, but will affect any additional alterations.
$hashref = $mock->sub_tracking
The tracking data looks like this:
{
sub_name => [
{sub_name => $sub_name, sub_ref => $mock_subref, args => [... copy of @_ from the call ... ]},
...,
...,
],
}
Unlike call_tracking, this lists all calls by sub, so you can choose to only look at the sub specific
calls.
Please note: The hashref items with the subname and args are shared with call_tracking, modifying one
modifies the other, so copy first!
$arrayref = $mock->call_tracking
The tracking data looks like this:
[
{sub_name => $sub_name, sub_ref => $mock_subref, args => [... copy of @_ from the call ... ]},
...,
...,
]
Unlike sub_tracking this lists all calls to any mocked sub, in the order they were called. To filter
by sub use sub_tracking.
Please note: The hashref items with the subname and args are shared with sub_tracking, modifying one
modifies the other, so copy first!
$mock->clear_sub_tracking()
$mock->clear_sub_tracking(\@subnames)
Clear tracking data. With no arguments ALL tracking data is cleared. When arguments are provided then
only those specific keys will be cleared.
$mock->clear_call_tracking()
Clear all items from call_tracking.
$mock->add('symbol' => ..., 'symbol2' => ...)
$mock->override('symbol1' => ..., 'symbol2' => ...)
$mock->set('symbol1' => ..., 'symbol2' => ...)
"add()" and "override()" are the primary ways to add/modify methods for a class. Both accept the
exact same type of arguments. The difference is that "override" will fail unless the symbol you are
overriding already exists, "add" on the other hand will fail if the symbol does already exist.
"set()" was more recently added for cases where you may not know if the sub already exists. These
cases are rare, and set should be avoided (think of it like 'no strict'). However there are valid use
cases, so it was added.
Note: Think of override as a push operation. If you call override on the same symbol multiple times
it will track that. You can use "restore()" as a pop operation to go back to the previous mock.
"reset" can be used to remove all the mocking for a symbol.
Arguments must be a symbol name, with optional sigil, followed by a new specification of the symbol.
If no sigil is specified then '&' (sub) is assumed. A simple example of overriding a sub:
$mock->override(foo => sub { 'overridden foo' });
my $val = $class->foo; # Runs our override
# $val is now set to 'overridden foo'
You can also simply provide a value and it will be wrapped in a sub for you:
$mock->override( foo => 'foo' );
The example above will generate a sub that always returns the string 'foo'.
There are three *special* values that can be used to generate accessors:
$mock->add(
name => 'rw', # Generates a read/write accessor
age => 'ro', # Generates a read only accessor
size => 'wo', # Generates a write only accessor
);
If you want to have a sub that actually returns one of the three special strings, or that returns a
coderef, you can use a hashref as the spec:
my $ref = sub { 'my sub' };
$mock->add(
rw_string => { val => 'rw' },
ro_string => { val => 'ro' },
wo_string => { val => 'wo' },
coderef => { val => $ref }, # the coderef method returns $ref each time
);
You can also override/add other symbol types, such as hash:
package Foo;
...
$mock->add('%foo' => {a => 1});
print $Foo::foo{a}; # prints '1'
You can also tell mock to deduce the symbol type for the add/override from the reference, rules are
similar to glob assignments:
$mock->add(
-foo => sub { 'foo' }, # Adds the &foo sub to the package
-foo => { foo => 1 }, # Adds the %foo hash to the package
-foo => [ 'f', 'o', 'o' ], # Adds the @foo array to the package
-foo => \"foo", # Adds the $foo scalar to the package
);
$mock->restore($SYMBOL)
Restore the symbol to what it was before the last override. If the symbol was recently added this
will remove it. If the symbol has been overridden multiple times this will ONLY restore it to the
previous state. Think of "override" as a push operation, and "restore" as the pop operation.
$mock->reset($SYMBOL)
Remove all mocking of the symbol and restore the original symbol. If the symbol was initially added
then it will be completely removed.
$mock->orig($SYMBOL)
This will return the original symbol, before any mocking. For symbols that were added this will
return undef.
$mock->current($SYMBOL)
This will return the current symbol.
$mock->reset_all
Remove all added symbols, and restore all overridden symbols to their originals.
$mock->add_constructor($NAME => $TYPE)
$mock->override_constructor($NAME => $TYPE)
This can be used to inject constructors. The first argument should be the name of the constructor.
The second argument specifies the constructor type.
The "hash" type is the most common, all arguments are used to create a new hash that is blessed.
hash => sub {
my ($class, %params) = @_;
return bless \%params, $class;
};
The "array" type is similar to the hash type, but accepts a list instead of key/value pairs:
array => sub {
my ($class, @params) = @_;
return bless \@params, $class;
};
The "ref" type takes a reference and blesses it. This will modify your original input argument.
ref => sub {
my ($class, $params) = @_;
return bless $params, $class;
};
The "ref_copy" type will copy your reference and bless the copy:
ref_copy => sub {
my ($class, $params) = @_;
my $type = reftype($params);
return bless {%$params}, $class
if $type eq 'HASH';
return bless [@$params], $class
if $type eq 'ARRAY';
croak "Not sure how to construct a '$class' from '$params'";
};
$mock->before($NAME, sub { ... })
This will replace the original sub $NAME with a new sub that calls your custom code just before
calling the original method. The return from your custom sub is ignored. Your sub and the original
both get the unmodified arguments.
$mock->after($NAME, sub { ... })
This is similar to before, except your callback runs after the original code. The return from your
callback is ignored.
$mock->around($NAME, sub { ... })
This gives you the chance to wrap the original sub:
$mock->around(foo => sub {
my $orig = shift;
my $self = shift;
my (@args) = @_;
...
$self->$orig(@args);
...
return ...;
});
The original sub is passed in as the first argument, even before $self. You are responsible for
making sure your wrapper sub returns the correct thing.
$mock->autoload
This will inject an "AUTOLOAD" sub into the class. This autoload will automatically generate read-
write accessors for any sub called that does not already exist.
$mock->block_load
This will prevent the real class from loading until the mock is destroyed. This will fail if the
class is already loaded. This will let you mock a class completely without loading the original
module.
$pm_file = $mock->file
This returns the relative path to the file for the module. This corresponds to the %INC entry.
$bool = $mock->purge_on_destroy($bool)
When true, this will cause the package stash to be completely obliterated when the mock object falls
out of scope or is otherwise destroyed. You do not normally want this.
$stash = $mock->stash
This returns the stash for the class being mocked. This is the equivalent of:
my $stash = \%{"${class}\::"};
This saves you from needing to turn off strict.
$class = $mock->class
The class being mocked by this instance.
$p = $mock->parent
If you mock a class twice the first instance is the parent, the second is the child. This prevents
the parent from being destroyed before the child, which would lead to a very unpleasant situation.
$c = $mock->child
Returns the child mock, if any.
SOURCE
The source code repository for Test2-Suite can be found at <https://github.com/Test-More/Test2-Suite/>.
MAINTAINERS
Chad Granum <exodist@cpan.org>
AUTHORS
Chad Granum <exodist@cpan.org>
COPYRIGHT
Copyright 2018 Chad Granum <exodist@cpan.org>.
This program is free software; you can redistribute it and/or modify it under the same terms as Perl
itself.
See <https://dev.perl.org/licenses/>
perl v5.36.0 2023-10-26 Test2::Mock(3pm)