NAME

       Test::MockModule - Override subroutines in a module for unit testing

SYNOPSIS

               use Module::Name;
               use Test::MockModule;

               {
                       my $module = Test::MockModule->new('Module::Name');
                       $module->mock('subroutine', sub { ... });
                       Module::Name::subroutine(@args); # mocked
               }

               Module::Name::subroutine(@args); # original subroutine

               # Working with objects
               use Foo;
               use Test::MockModule;
               {
                       my $mock = Test::MockModule('Foo');
                       $mock->mock(foo => sub { print "Foo!\n"; });

                       my $foo = Foo->new();
                       $foo->foo(); # prints "Foo!\n"
               }

DESCRIPTION

       "Test::MockModule" lets you temporarily redefine subroutines in other packages for the purposes of unit
       testing.

       A "Test::MockModule" object is set up to mock subroutines for a given module. The object remembers the
       original subroutine so it can be easily restored. This happens automatically when all MockModule objects
       for the given module go out of scope, or when you "unmock()" the subroutine.

METHODS

       new($package[, %options])
           Returns an object that will mock subroutines in the specified $package.

           If  there  is  no  $VERSION  defined  in  $package,  the module will be automatically loaded. You can
           override this behaviour by setting the "no_auto" option:

                   my $mock = Test::MockModule->new('Module::Name', no_auto => 1);

       get_package()
           Returns the target package name for the mocked subroutines

       is_mocked($subroutine)
           Returns a boolean value indicating whether or not the subroutine is currently mocked

       mock($subroutine => \&coderef)
           Temporarily replaces one or more subroutines in the mocked module. A subroutine can be mocked with  a
           code reference or a scalar. A scalar will be recast as a subroutine that returns the scalar.

           The following statements are equivalent:

                   $module->mock(purge => 'purged');
                   $module->mock(purge => sub { return 'purged'});

           When  dealing  with  references, things behave slightly differently. The following statements are NOT
           equivalent:

                   # Returns the same arrayref each time, with the localtime() at time of mocking
                   $module->mock(updated => [localtime()]);
                   # Returns a new arrayref each time, with up-to-date localtime() value
                   $module->mock(updated => sub { return [localtime()]});

           The following statements are in fact equivalent:

                   my $array_ref = [localtime()]
                   $module->mock(updated => $array_ref)
                   $module->mock(updated => sub { return $array_ref });

           However, "undef" is a special case. If you mock a subroutine with "undef" it will  install  an  empty
           subroutine

                   $module->mock(purge => undef);
                   $module->mock(purge => sub { });

           rather than a subroutine that returns "undef":

                   $module->mock(purge => sub { undef });

           You  can call "mock()" for the same subroutine many times, but when you call "unmock()", the original
           subroutine is restored (not the last mocked instance).

           MOCKING + EXPORT

           If you are trying to mock a subroutine exported from another module,  this  may  not  behave  as  you
           initialy  would  expect,  since  Test::MockModule  is only mocking at the target module, not anything
           importing that module. If you mock the local package, or use a fully  qualified  function  name,  you
           will get the behavior you desire:

                   use Test::MockModule;
                   use Test::More;
                   use POSIX qw/strftime/;

                   my $posix = Test::MockModule->new("POSIX");

                   $posix->mock("strftime", "Yesterday");
                   is strftime("%D", localtime(time)), "Yesterday", "`strftime` was mocked successfully"; # Fails
                   is POSIX::strftime("%D", localtime(time)), "Yesterday", "`strftime` was mocked successfully"; # Succeeds

                   my $main = Test::MockModule->new("main", no_auto => 1);
                   $main->mock("strftime", "today");
                   is strftime("%D", localtime(time)), "today", "`strftime` was mocked successfully"; # Succeeds

           If  you  are  trying to mock a subroutine that was exported into a module that you're trying to test,
           rather than mocking the subroutine in its originating module, you can instead mock it in  the  module
           you are testing:

                   package MyModule;
                   use POSIX qw/strftime/;

                   sub minus_twentyfour
                   {
                           return strftime("%a, %b %d, %Y", localtime(time - 86400));
                   }

                   package main;
                   use Test::More;
                   use Test::MockModule;

                   my $posix = Test::MockModule->new("POSIX");
                   $posix->mock("strftime", "Yesterday");

                   is MyModule::minus_twentyfour(), "Yesterday", "`minus-tewntyfour` got mocked"; # fails

                   my $mymodule = Test::MockModule->new("MyModule", no_auto => 1);
                   $mymodule->mock("strftime", "Yesterday");
                   is MyModule::minus_twentyfour(), "Yesterday", "`minus-tewntyfour` got mocked"; # suceeds

       original($subroutine)
           Returns the original (unmocked) subroutine

       unmock($subroutine [, ...])
           Restores the original $subroutine. You can specify a list of subroutines to "unmock()" in one go.

       unmock_all()
           Restores  all  the subroutines in the package that were mocked. This is automatically called when all
           "Test::MockObject" objects for the given package go out of scope.

SEE ALSO

       Test::MockObject::Extends

       Sub::Override

AUTHORS

       Current Maintainer: Geoff Franks <gfranks@cpan.org>

       Original Author: Simon Flack <simonflk _AT_ cpan.org>

COPYRIGHT

       Copyright 2004 Simon Flack <simonflk _AT_ cpan.org>.  All rights reserved

       You may distribute under the terms of either the GNU General Public License or the Artistic  License,  as
       specified in the Perl README file.

perl v5.20.2                                       2015-11-01                              Test::MockModule(3pm)