Dist::Zilla::Plugin::Test::CheckBreaks - Generate a test that shows what modules you are breaking


version 0.019


In your dist.ini:

    Foo = <= 1.1    ; Foo at 1.1 or lower will break when I am installed

    conflicts_module = Moose::Conflicts


This is a Dist::Zilla plugin that runs at the gather files stage, providing a test file that runs last in your test suite and checks for conflicting modules, as indicated by x_breaks in your distribution metadata. (See the t/zzz-check-breaks.t test in this distribution for an example.)

x_breaks entries are expected to be version ranges, with one addition, for backwards compatibility with [Conflicts]: if a bare version number is specified, it is interpreted as '<= $version' (to preserve the intent that versions at or below the version specified are those considered to be broken). It is possible that this interpretation will be removed in the future; almost certainly before breaks becomes a formal part of the meta specification.



The name of the conflicts module to load and upon which to invoke the check_conflicts method. Defaults to the name of the main module with '::Conflicts' appended, such as what is generated by the [Conflicts] plugin.

If your distribution uses Moose but does not itself generate a conflicts plugin, then Moose::Conflicts is an excellent choice, as there are numerous interoperability conflicts catalogued in that module.

There is no error if the module does not exist. This test does not require [Conflicts] to be used in your distribution; this is only a feature added for backwards compatibility.

This option can be used more than once starting with version 0.017.


Suitable for distributions that do not wish to add a test requires prerequisite on CPAN::Meta::Requirements and CPAN::Meta::Check -- instead, the dependencies will be added as test suggests, and the generated test will gracefully skip checks if these modules are not available.

Available since version 0.015.


I came upon this idea for a test after handling a bug report I've seen many times before when dealing with Moose code: "hey, when I updated Moose, my other thing that uses Moose stopped working!" For quite some time Moose has generated breakage information in the form of the moose-outdated executable and a check in Makefile.PL (which uses the generated module Moose::Conflicts), but the output is usually buried in the user's install log or way up in the console buffer, and so doesn't get acted on nearly as often as it should. I realized it would be a simple matter to re-run the executable at the very end of tests by crafting a filename that always sorts (and runs) last, and further that we could generate this test. This coincided nicely with conversations on irc #toolchain about the x_breaks metadata field and plans for its future. Therefore, this distribution, and its sister plugin [Breaks] were born!



Bugs may be submitted through the RT bug tracker (or

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Karen Etheridge <>


Olivier Mengué <>


This software is copyright (c) 2014 by Karen Etheridge.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.