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Test::Unit - Procedural style unit testing interface


    use Test::Unit;

    # your code to be tested goes here

    sub foo { return 23 };
    sub bar { return 42 };

    # define tests

    sub test_foo { assert(foo() == 23, "Your message here"); }  
    sub test_bar { assert(bar() == 42, "I will be printed if this fails"); }

    # set_up and tear_down are used to
    # prepare and release resources need for testing

    sub set_up    { print "hello world\n"; }
    sub tear_down { print "leaving world again\n"; }

    # run your test



Test::Unit is the procedural style interface to a sophisticated unit testing framework for Perl that is derived from the JUnit testing framework for Java by Kent Beck and Erich Gamma. While this framework is originally intended to support unit testing in an object-oriented development paradigm (with support for inheritance of tests etc.), Test::Unit is intended to provide a simpler interface to the framework that is more suitable for use in a scripting style environment. Therefore, Test::Unit does not provide much support for an object-oriented approach to unit testing - if you want that, please have a look at Test::Unit::TestCase.

You test a given unit (a script, a module, whatever) by using Test::Unit, which exports the following routines into your namespace:


used to assert that a boolean condition is true


used to create a test suite consisting of all methods with a name prefix of test


runs the test suite (text output)


used to add test suites to each other

For convenience, create_suite() will automatically build a test suite for a given package. This will build a test case for each subroutine in the package given that has a name starting with test and pack them all together into one TestSuite object for easy testing. If you dont give a package name to create_suite(), the current package is taken as default.

Test output is one status line (a "." for every successful test run, or an "F" for any failed test run, to indicate progress), one result line ("OK" or "!!!FAILURES!!!"), and possibly many lines reporting detailed error messages for any failed tests.

Please remember, Test::Unit is intended to be a simple and convenient interface. If you need more functionality, take the object-oriented approach outlined in Test::Unit::TestCase.


Copyright (c) 2000, 2001 Christian Lemburg, <>.

All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

Thanks go to the other PerlUnit framework people: Brian Ewins, Cayte Lindner, J.E. Fritz, Zhon Johansen, Matthew Astley, Adam Spiers, Piers Cawley.

Thanks for patches and other contributions go to: David Esposito, Kevin Connor.