You are viewing the version of this documentation from Perl 5.005_02. View the latest version



Test - provides a simple framework for writing test scripts


use strict;
use Test;
BEGIN { plan tests => 13, todo => [3,4] }

ok(0); # failure
ok(1); # success

ok(0); # ok, expected failure (see todo list, above)
ok(1); # surprise success!

ok(0,1);             # failure: '0' ne '1'
ok('broke','fixed'); # failure: 'broke' ne 'fixed'
ok('fixed','fixed'); # success: 'fixed' eq 'fixed'

ok(sub { 1+1 }, 2);  # success: '2' eq '2'
ok(sub { 1+1 }, 3);  # failure: '2' ne '3'
ok(0, int(rand(2));  # (just kidding! :-)

my @list = (0,0);
ok @list, 3, "\@list=".join(',',@list);      #extra diagnostics
ok 'segmentation fault', '/(?i)success/';    #regex match

skip($feature_is_missing, ...);    #do platform specific test


Test::Harness expects to see particular output when it executes tests. This module aims to make writing proper test scripts just a little bit easier (and less error prone :-).



BEGIN { plan test => 4, onfail => sub { warn "CALL 911!" } }

The test failures can trigger extra diagnostics at the end of the test run. onfail is passed an array ref of hash refs that describe each test failure. Each hash will contain at least the following fields: package, repetition, and result. (The file, line, and test number are not included because their correspondance to a particular test is fairly weak.) If the test had an expected value or a diagnostic string, these will also be included.

This optional feature might be used simply to print out the version of your package and/or how to report problems. It might also be used to generate extremely sophisticated diagnostics for a particular test failure. It's not a panacea, however. Core dumps or other unrecoverable errors will prevent the onfail hook from running. (It is run inside an END block.) Besides, onfail is probably over-kill in the majority of cases. (Your test code should be simpler than the code it is testing, yes?)


Test::Harness and various test coverage analysis tools.


Copyright (C) 1998 Joshua Nathaniel Pritikin. All rights reserved.

This package is free software and is provided "as is" without express or implied warranty. It may be used, redistributed and/or modified under the terms of the Perl Artistic License (see