Test2:...Subtest(3perl) Perl Programmers Reference GuideTest2:...Subtest(3perl)
NAME
Test2::Tools::Subtest - Tools for writing subtests
DESCRIPTION
This package exports subs that let you write subtests.
There are two types of subtests, buffered and streamed. Streamed
subtests mimic subtests from Test::More in that they render all events
as soon as they are produced. Buffered subtests wait until the subtest
completes before rendering any results.
The main difference is that streamed subtests are unreadable when
combined with concurrency. Buffered subtests look fine with any number
of concurrent threads and processes.
SYNOPSIS
BUFFERED
use Test2::Tools::Subtest qw/subtest_buffered/;
subtest_buffered my_test => sub {
ok(1, "subtest event A");
ok(1, "subtest event B");
};
This will produce output like this:
ok 1 - my_test {
ok 1 - subtest event A
ok 2 - subtest event B
1..2
}
STREAMED
The default option is 'buffered'. If you want streamed subtests, the way
Test::Builder does it, use this:
use Test2::Tools::Subtest qw/subtest_streamed/;
subtest_streamed my_test => sub {
ok(1, "subtest event A");
ok(1, "subtest event B");
};
This will produce output like this:
# Subtest: my_test
ok 1 - subtest event A
ok 2 - subtest event B
1..2
ok 1 - Subtest: my_test
IMPORTANT NOTE
You can use "bail_out" or "skip_all" in a subtest, but not in a BEGIN
block or "use" statement. This is due to the way flow control works
within a BEGIN block. This is not normally an issue, but can happen in
rare conditions using eval, or script files as subtests.
EXPORTS
subtest_streamed $name => $sub
subtest_streamed($name, $sub, @args)
subtest_streamed $name => \%params, $sub
subtest_streamed($name, \%params, $sub, @args)
Run subtest coderef, stream events as they happen.
"\%params" is a hashref with any arguments you wish to pass into hub
construction.
subtest_buffered $name => $sub
subtest_buffered($name, $sub, @args)
subtest_buffered $name => \%params, $sub
subtest_buffered($name, \%params, $sub, @args)
Run subtest coderef, render events all at once when subtest is
complete.
"\%params" is a hashref with any arguments you wish to pass into hub
construction.
SOURCE
The source code repository for Test2-Suite can be found at
https://github.com/Test-More/Test2-Suite/.
MAINTAINERS
Chad Granum <exodist@cpan.org>
AUTHORS
Chad Granum <exodist@cpan.org>
COPYRIGHT
Copyright 2018 Chad Granum <exodist@cpan.org>.
This program is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.
See http://dev.perl.org/licenses/
perl v5.40.1 2026-08-30 Test2:...Subtest(3perl)
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