NAME

Test2::Manual::Tooling::Plugin::ToolStarts - How to add behaviors that occur when a tool starts work.

DESCRIPTION

This tutorial will help you write plugins that have behavior when a tool starts. All tools should start by acquiring a context object. This tutorial shows you the hooks you can use to take advantage of the context acquisition.

COMPLETE CODE UP FRONT

package Test2::Plugin::MyPlugin;

use Test2::API qw{
    test2_add_callback_context_init
    test2_add_callback_context_acquire
};

sub import {
    my $class = shift;

    # Let us know every time a tool requests a context, and give us a
    # chance to modify the parameters before we find it.
    test2_add_callback_context_acquire(sub {
        my $params_ref = shift;

        print "A tool has requested the context\n";
    });

    # Callback every time a new context is created, not called if an
    # existing context is found.
    test2_add_callback_context_init(sub {
        my $ctx_ref = shift;

        print "A new context was created\n";
    });
}

1;

LINE BY LINE

use Test2::API qw{test2_add_callback_context_init test2_add_callback_context_acquire};

This imports the test2_add_callback_context_init() and test2_add_callback_context_acquire() callbacks.

test2_add_callback_context_acquire(sub { ... })

This is where we add our callback for context acquisition. Every time Test2::API::context() is called the callback will be run.

my $params_ref = shift

In the test2_add_callback_context_acquire() callbacks we get exactly 1 argument, a reference to the parameters that context() will use to find the context.

print "A tool has requested the context\n"

Print a notification whenever a tool asks for a context.

test2_add_callback_context_init(sub { ... })

Add our context init callback. These callbacks are triggered whenever a completely new context is created. This is not called if an existing context is found. In short this only fires off for the top level tool, not nested tools.

my $ctx_ref = shift

The coderefs for test2_add_callback_context_init() will receive exactly 1 argument, the newly created context.

print "A new context was created\n"

Print a notification whenever a new context is created.

SEE ALSO

Test2::Manual - Primary index of the manual.

SOURCE

The source code repository for Test2-Manual 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/