Test::Unit::Assertion::Regexp - Assertion with regex matching


    require Test::Unit::Assertion::Regexp;

    my $assert_re =


This is rather more detail than the average user will need. Test::Unit::Assertion::Regexp objects are generated automagically by Test::Unit::Assert::assert when it is passed a regular expression as its first parameter.

    sub test_foo {
      $self->assert(qr/some_pattern/, $result);

If the assertion fails then the object throws an exception with details of the pattern and the string it failed to match against.

Note that if you need to do a 'string does not match this pattern' type of assertion then you can do:

   $self->assert(qr/(?!some_pattern)/, $some_string)

ie. Make use of the negative lookahead assertion.


Test::Unit::Assertion::Regexp implements the Test::Unit::Assertion interface, which means it can be plugged into the Test::Unit::TestCase and friends' assert method with no ill effects.


The class is used by the framework to provide sensible 'automatic' reports when a match fails. The old:

    $self->assert(scalar($foo =~ /pattern/), "$foo didn't match /.../");

seems rather clumsy compared to this. If the regexp assertion fails, then the user is given a sensible error message, with the pattern and the string that failed to match it...


Copyright (c) 2001 Piers Cawley <>.

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