Test2::Manual::Tooling::Formatter(3perl) - Man pages

Test2:...rmatter(3perl) Perl Programmers Reference GuideTest2:...rmatter(3perl)

NAME
       Test2::Manual::Tooling::Formatter - How to write a custom formatter, in
       our case a JSONL formatter.

DESCRIPTION
       This tutorial explains a minimal formatter that outputs each event as a
       json string on its own line. A true formatter will probably be
       significantly more complicated, but this will give you the basics needed
       to get started.

COMPLETE CODE UP FRONT
           package Test2::Formatter::MyFormatter;
           use strict;
           use warnings;

           use JSON::MaybeXS qw/encode_json/;

           use base qw/Test2::Formatter/;

           sub new { bless {}, shift }

           sub encoding {};

           sub write {
               my ($self, $e, $num, $f) = @_;
               $f ||= $e->facet_data;

               print encode_json($f), "\n";
           }

           1;

LINE BY LINE
       use base qw/Test2::Formatter/;
           All formatters should inherit from Test2::Formatter.

       sub new { bless {}, shift }
           Formatters  need to be instantiable objects, this is a minimal new()
           method.

       sub encoding {};
           For this example we leave this sub  empty.  In  general  you  should
           implement  this  sub  to  make  sure  you honor situations where the
           encoding is set. Test2::V0 itself will try to set  the  encoding  to
           UTF8.

       sub write { ... }
           The write() method is the most important, each event is sent here.

       my ($self, $e, $num, $f) = @_;
           The  write()  method  receives  3  or  4  arguments,  the  fourth is
           optional.

           $self
               The formatter itself.

           $e  The event being written

           $num
               The most recent assertion number. If the event  being  processed
               is  an  assertion then this will have been bumped by 1 since the
               last call to write. For non assertions this number is set to the
               most recent assertion.

           $f  This MAY be a hashref containing all the  facet  data  from  the
               event.  More often then not this will be undefined. This is only
               set if the facet data was needed by the hub, and it  usually  is
               not.

       $f ||= $e->facet_data;
           We  want to dump the event facet data. This will set $f to the facet
           data unless we already have the facet data.

       print encode_json($f), "\n";
           This line prints the JSON encoded facet data, and a newline.

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/

perl v5.40.1                       2026-08-30           Test2:...rmatter(3perl)

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