README   [plain text]


NAME
    Test::Exception - Test exception based code

SYNOPSIS
      use Test::More tests => 5;
      use Test::Exception;

      # or if you don't need Test::More

      use Test::Exception tests => 5;

      # then...

      # Check that something died
      dies_ok { $foo->method1 } 'expecting to die';

      # Check that something did not die
      lives_ok { $foo->method2 } 'expecting to live';

      # Check that the stringified exception matches given regex
      throws_ok { $foo->method3 } qr/division by zero/, 'zero caught okay';

      # Check an exception of the given class (or subclass) is thrown
      throws_ok { $foo->method4 } 'Error::Simple', 'simple error thrown';
      
  # all Test::Exceptions subroutines are guaranteed to preserve the state 
      # of $@ so you can do things like this after throws_ok and dies_ok
      like $@, 'what the stringified exception should look like';

      # Check that a test runs without an exception
      lives_and { is $foo->method, 42 } 'method is 42';
      
  # or if you don't like prototyped functions
      
  dies_ok( sub { $foo->method1 }, 'expecting to die' );
      lives_ok( sub { $foo->method2 }, 'expecting to live' );
      throws_ok( sub { $foo->method3 }, qr/division by zero/,
          'zero caught okay' );
      throws_ok( sub { $foo->method4 }, 'Error::Simple', 
          'simple error thrown' );
      lives_and( sub { is $foo->method, 42 }, 'method is 42' );

DESCRIPTION
    This module provides a few convenience methods for testing exception
    based code. It is built with Test::Builder and plays happily with
    Test::More and friends.

    If you are not already familiar with Test::More now would be the time to
    go take a look.

    You can specify the test plan when you "use Test::Exception" in the same
    way as "use Test::More". See Test::More for details.

    dies_ok
        Checks that a piece of code dies, rather than returning normally.
        For example:

            sub div {
                my ( $a, $b ) = @_;
                return $a / $b;
            };

            dies_ok { div( 1, 0 ) } 'divide by zero detected';

            # or if you don't like prototypes
            dies_ok( sub { div( 1, 0 ) }, 'divide by zero detected' );

        A true value is returned if the test succeeds, false otherwise. On
        exit $@ is guaranteed to be the cause of death (if any).

        The test description is optional, but recommended.

    lives_ok
        Checks that a piece of code exits normally, and doesn't die. For
        example:

            sub read_file {
                my $file = shift;
                local $/;
                open my $fh, '<', $file or die "open failed ($!)\n";
                $file = <FILE>;
                return $file;
            };

            my $file;
            lives_ok { $file = read_file('test.txt') } 'file read';

            # or if you don't like prototypes
            lives_ok( sub { $file = read_file('test.txt') }, 'file read' );

        Should a lives_ok() test fail it produces appropriate diagnostic
        messages. For example:

            not ok 1 - file read
            #     Failed test (test.t at line 15)
            # died: open failed (No such file or directory)

        A true value is returned if the test succeeds, false otherwise. On
        exit $@ is guaranteed to be the cause of death (if any).

        The test description is optional, but recommended.

    throws_ok
        Tests to see that a specific exception is thrown. throws_ok() has
        two forms:

          throws_ok BLOCK REGEX, TEST_DESCRIPTION
          throws_ok BLOCK CLASS, TEST_DESCRIPTION

        In the first form the test passes if the stringified exception
        matches the give regular expression. For example:

            throws_ok { read_file( 'unreadable' ) } qr/No file/, 'no file';

        If your perl does not support "qr//" you can also pass a regex-like
        string, for example:

            throws_ok { read_file( 'unreadable' ) } '/No file/', 'no file';

        The second form of throws_ok() test passes if the exception is of
        the same class as the one supplied, or a subclass of that class. For
        example:

            throws_ok { $foo->bar } "Error::Simple", 'simple error';

        Will only pass if the "bar" method throws an Error::Simple
        exception, or a subclass of an Error::Simple exception.

        You can get the same effect by passing an instance of the exception
        you want to look for. The following is equivalent to the previous
        example:

            my $SIMPLE = Error::Simple->new;
            throws_ok { $foo->bar } $SIMPLE, 'simple error';

        Should a throws_ok() test fail it produces appropriate diagnostic
        messages. For example:

            not ok 3 - simple error
            #     Failed test (test.t at line 48)
            # expecting: Error::Simple exception
            # found: normal exit

        Like all other Test::Exception functions you can avoid prototypes by
        passing a subroutine explicitly:

            throws_ok( sub {$foo->bar}, "Error::Simple", 'simple error' );

        A true value is returned if the test succeeds, false otherwise. On
        exit $@ is guaranteed to be the cause of death (if any).

        A description of the exception being checked is used if no optional
        test description is passed.

    lives_and
        Run a test that may throw an exception. For example, instead of
        doing:

          my $file;
          lives_ok { $file = read_file('answer.txt') } 'read_file worked';
          is $file, "42", 'answer was 42';

        You can use lives_and() like this:

          lives_and { is read_file('answer.txt'), "42" } 'answer is 42';
          # or if you don't like prototypes
          lives_and(sub {is read_file('answer.txt'), "42"}, 'answer is 42');

        Which is the same as doing

          is read_file('answer.txt'), "42\n", 'answer is 42';

        unless "read_file('answer.txt')" dies, in which case you get the
        same kind of error as lives_ok()

          not ok 1 - answer is 42
          #     Failed test (test.t at line 15)
          # died: open failed (No such file or directory)

        A true value is returned if the test succeeds, false otherwise. On
        exit $@ is guaranteed to be the cause of death (if any).

        The test description is optional, but recommended.

SKIPPING TEST::EXCEPTION TESTS
    Sometimes we want to use Test::Exception tests in a test suite, but
    don't want to force the user to have Test::Exception installed. One way
    to do this is to skip the tests if Test::Exception is absent. You can do
    this with code something like this:

      use strict;
      use warnings;
      use Test::More;
      
  BEGIN {
          eval "use Test::Exception";
          plan skip_all => "Test::Exception needed" if $@;
      }
      
  plan tests => 2;
      # ... tests that need Test::Exception ...

    Note that we load Test::Exception in a "BEGIN" block ensuring that the
    subroutine prototypes are in place before the rest of the test script is
    compiled.

BUGS
    None known at the time of writing.

    If you find any please let me know by e-mail, or report the problem with
    <http://rt.cpan.org/>.

COMMUNITY
    perl-qa
        If you are interested in testing using Perl I recommend you visit
        <http://qa.perl.org/> and join the excellent perl-qa mailing list.
        See <http://lists.perl.org/showlist.cgi?name=perl-qa> for details on
        how to subscribe.

    perlmonks
        You can find users of Test::Exception, including the module author,
        on <http://www.perlmonks.org/>. Feel free to ask questions on
        Test::Exception there.

    CPAN::Forum
        The CPAN Forum is a web forum for discussing Perl's CPAN modules.
        The Test::Exception forum can be found at
        <http://www.cpanforum.com/dist/Test-Exception>.

    AnnoCPAN
        AnnoCPAN is a web site that allows community annotations of Perl
        module documentation. The Test::Exception annotations can be found
        at <http://annocpan.org/~ADIE/Test-Exception/>.

TO DO
    If you think this module should do something that it doesn't (or does
    something that it shouldn't) please let me know.

    You can see my current to do list at
    <http://adrianh.tadalist.com/lists/public/15421>, with an RSS feed of
    changes at <http://adrianh.tadalist.com/lists/feed_public/15421>.

ACKNOWLEDGMENTS
    Thanks to chromatic and Michael G Schwern for the excellent
    Test::Builder, without which this module wouldn't be possible.

    Thanks to Adam Kennedy, Andy Lester, Aristotle, Ben Prew, Cees Hek,
    chromatic, Curt Sampson, David Golden, David Wheeler, Janek Schleicher,
    Jim Keenan, Jos I. Boumans, Jost Krieger, Mark Fowler, Michael G
    Schwern, Paul McCann, Perrin Harkins, Peter Scott, Rob Muhlestein Scott
    R. Godin, Steve Purkis, Steve, Tim Bunce, and various anonymous folk for
    comments, suggestions, bug reports and patches.

AUTHOR
    Adrian Howard <adrianh@quietstars.com>

    If you can spare the time, please drop me a line if you find this module
    useful.

SEE ALSO
    Test::Builder
        Support module for building test libraries.

    Test::Simple & Test::More
        Basic utilities for writing tests.

    Test::Warn & Test::NoWarnings
        Modules to help test warnings.

    <http://qa.perl.org/test-modules.html>
        Overview of some of the many testing modules available on CPAN.

    <http://del.icio.us/tag/Test::Exception>
        Delicious links on Test::Exception.

    <http://del.icio.us/tag/perl+testing>
        Delicious links on perl testing.

LICENCE
    Copyright 2002-2006 Adrian Howard, All Rights Reserved.

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