Test::File::IsSorted - test files for being lexicographical sorted.


version 0.2.0


    use Test::More tests => 1;

    use Test::File::IsSorted ();

    # TEST
    Test::File::IsSorted::are_sorted([".gitignore", "MANIFEST.SKIP"],
        "Files are sorted");


This checks if the lines of files or filehandles are monotonically and lexicographically increasing, (= are already sorted). It may consume less RAM and be faster than the naive way of doing cmp myfile.txt <(LC_ALL=C sort myfile.txt) and it runs at O(n) instead of O(n*log(n)) time and keeps O(1) lines instead of O(n).


are_sorted([@paths], $blurb);

Checks if all of the filesystem paths are sorted.

are_sorted2([@paths], $blurb);

Checks if all of the filesystem paths are sorted. Also checks that @paths are sorted.

Added in version v0.2.0.



The following websites have more information about this module, and may be of help to you. As always, in addition to those websites please use your favorite search engine to discover more resources.

Bugs / Feature Requests

Please report any bugs or feature requests by email to bug-file-issorted at, or through the web interface at You will be automatically notified of any progress on the request by the system.

Source Code

The code is open to the world, and available for you to hack on. Please feel free to browse it and play with it, or whatever. If you want to contribute patches, please send me a diff or prod me to pull from your repository :)

  git clone


Shlomi Fish <>


Please report any bugs or feature requests on the bugtracker website

When submitting a bug or request, please include a test-file or a patch to an existing test-file that illustrates the bug or desired feature.


This software is Copyright (c) 2019 by Shlomi Fish.

This is free software, licensed under:

  The MIT (X11) License