Test2::Manual::Tooling::Plugin::ToolStarts3p

Overview

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.

Source

The source code repository for Test2-Manual can be found at https://github.com/Test-More/test-more/.

Maintainers

Chad Granum <[email protected]>