Test2:...Subtest(3perl) Perl Programmers Reference GuideTest2:...Subtest(3perl)
NAME
Test2::AsyncSubtest - Object representing an async subtest.
DESCRIPTION
Regular subtests have a limited scope, they start, events are generated,
then they close and send an Test2::Event::Subtest event. This is a
problem if you want the subtest to keep receiving events while other
events are also being generated. This class implements subtests that
stay open until you decide to close them.
This is mainly useful for tools that start a subtest in one process and
then spawn children. In many cases it is nice to let the parent process
continue instead of waiting on the children.
SYNOPSIS
use Test2::AsyncSubtest;
my $ast = Test2::AsyncSubtest->new(name => foo);
$ast->run(sub {
ok(1, "Event in parent" );
});
ok(1, "Event outside of subtest");
$ast->run_fork(sub {
ok(1, "Event in child process");
});
...
$ast->finish;
done_testing;
CONSTRUCTION
my $ast = Test2::AsyncSubtest->new( ... );
name => $name (required)
Name of the subtest. This construction argument is required.
send_to => $hub (optional)
Hub to which the final subtest event should be sent. This must be an
instance of Test2::Hub or a subclass. If none is specified then the
current top hub will be used.
trace => $trace (optional)
File/Line to which errors should be attributed. This must be an
instance of Test2::Util::Trace. If none is specified then the
file/line where the constructor was called will be used.
hub => $hub (optional)
Use this to specify a hub the subtest should use. By default a new
hub is generated. This must be an instance of
Test2::AsyncSubtest::Hub.
METHODS
SIMPLE ACCESSORS
$bool = $ast->active
True if the subtest is active. The subtest is active if its hub
appears in the global hub stack. This is true when "$ast->run(...)"
us running.
$arrayref = $ast->children
Get an arrayref of child processes/threads. Numerical items are
PIDs, blessed items are threads instances.
$arrayref = $ast->events
Get an arrayref of events that have been sent to the subtests hub.
$bool = $ast->finished
True if finished() has already been called.
$hub = $ast->hub
The hub created for the subtest.
$int = $ast->id
Attach/Detach counter. Used internally, not useful to users.
$str = $ast->name
Name of the subtest.
$pid = $ast->pid
PID in which the subtest was created.
$tid = $ast->tid
Thread ID in which the subtest was created.
$hub = $ast->send_to
Hub to which the final subtest event should be sent.
$arrayref = $ast->stack
Stack of async subtests at the time this one was created. This is
mainly for internal use.
$trace = $ast->trace
Test2::Util::Trace instance used for error reporting.
INTERFACE
$ast->attach($id)
Attach a subtest in a child/process to the original.
Note: "my $id = $ast->cleave" must have been called in the parent
process/thread before the child was started, the id it returns must
be used in the call to "$ast->attach($id)"
$id = $ast->cleave
Prepare a slot for a child process/thread to attach. This must be
called BEFORE the child process or thread is started. The ID
returned is used by attach().
This must only be called in the original process/thread.
$ctx = $ast->context
Get an Test2::API::Context instance that can be used to send events
to the context in which the hub was created. This is not a canonical
context, you should not call "$ctx->release" on it.
$ast->detach
Detach from the parent in a child process/thread. This should be
called just before the child exits.
$ast->finish
$ast->finish(%options)
Finish the subtest, wait on children, and send the final subtest
event.
This must only be called in the original process/thread.
Note: This calls "$ast->wait".
These are the options:
collapse => 1
This intelligently allows a subtest to be empty.
If no events bump the test count then the subtest no final plan
will be added. The subtest will not be considered a failure
(normally an empty subtest is a failure).
If there are no events at all the subtest will be collapsed into
an Test2::Event::Ok event.
silent => 1
This will prevent finish from generating a final
Test2::Event::Subtest event. This effectively ends the subtest
without it effecting the parent subtest (or top level test).
no_plan => 1
This will prevent a final plan from being added to the subtest
for you when none is directly specified.
skip => "reason"
This will issue an Test2::Event::Skip instead of a subtest. This
will throw an exception if any events have been seen, or if
state implies events have occurred.
$out = $ast->fork
This is a slightly higher level interface to fork. Running it will
fork your code in-place just like fork(). It will return a pid in
the parent, and an Test2::Util::Guard instance in the child. An
exception will be thrown if fork fails.
It is recommended that you use "$ast->run_fork(sub { ... })"
instead.
$bool = $ast->pending
True if there are child processes, threads, or subtests that depend
on this one.
$bool = $ast->ready
This is essentially "!$ast->pending".
$ast->run(sub { ... })
Run the provided codeblock inside the subtest. This will push the
subtest hub onto the stack, run the code, then pop the hub off the
stack.
$pid = $ast->run_fork(sub { ... })
Same as "$ast->run()", except that the codeblock is run in a child
process.
You do not need to directly call wait($pid), that will be done for
you when "$ast->wait", or "$ast->finish" are called.
my $thr = $ast->run_thread(sub { ... });
** DISCOURAGED ** Threads cause problems. This method remains for
anyone who REALLY wants it, but it is no longer supported. Tests for
this functionality do not even run unless the AUTHOR_TESTING or
T2_DO_THREAD_TESTS env vars are enabled.
Same as "$ast->run()", except that the codeblock is run in a child
thread.
You do not need to directly call "$thr->join", that is done for you
when "$ast->wait", or "$ast->finish" are called.
$passing = $ast->start
Push the subtest hub onto the stack. Returns the current pass/fail
status of the subtest.
$ast->stop
Pop the subtest hub off the stack. Returns the current pass/fail
status of the subtest.
$ast->wait
Wait on all threads/processes that were started using "$ast->fork",
"$ast->run_fork", or "$ast->run_thread".
SOURCE
The source code repository for Test2-AsyncSubtest 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 <exodist7@gmail.com>.
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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