Test::Without::Module - Test fallback behaviour in absence of modules


  use Test::Without::Module qw( My::Module );

  # Now, loading of My::Module fails :
  eval { require My::Module; };
  warn $@ if $@;

  # Now it works again
  eval q{ no Test::Without::Module qw( My::Module ) };
  eval { require My::Module; };
  print "Found My::Module" unless $@;


This module allows you to deliberately hide modules from a program even though they are installed. This is mostly useful for testing modules that have a fallback when a certain dependency module is not installed.


None. All magic is done via use Test::Without::Module LIST and no Test::Without::Module LIST.


This function returns a reference to a copy of the current hash of forbidden modules or an empty hash if none are currently forbidden. This is convenient if you are testing and/or debugging this module.


A neat trick for using this module from the command line was mentioned to me by NUFFIN:

  perl -MTest::Without::Module=Some::Module -w -Iblib/lib t/SomeModule.t

That way, you can easily see how your module or test file behaves when a certain module is unavailable.



Much improvement must be thanked to Aristotle from PerlMonks, he pointed me to a much less convoluted way to fake a module at

I also discussed with him an even more elegant way of overriding CORE::GLOBAL::require, but the parsing of the overridden subroutine didn't work out the way I wanted it - CORE::require didn't recognize barewords as such anymore.

NUFFIN and Jerrad Pierce pointed out the convenient use from the command line to interactively watch the behaviour of the test suite and module in absence of a module.


Copyright (c) 2003-2007 Max Maischein, <>


This module is released under the same terms as Perl itself.


Devel::Hide, Acme::Intraweb, PAR, perlfunc