TAP::Parser::IteratorFactory(3p) Perl Programmers Reference Guide #

TAP::Parser::IteratorFactory(3p) Perl Programmers Reference Guide

NNAAMMEE #

 TAP::Parser::IteratorFactory - Figures out which SourceHandler objects to
 use for a given Source

VVEERRSSIIOONN #

 Version 3.44

SSYYNNOOPPSSIISS #

   use TAP::Parser::IteratorFactory;
   my $factory = TAP::Parser::IteratorFactory->new({ %config });
   my $iterator  = $factory->make_iterator( $filename );

DDEESSCCRRIIPPTTIIOONN #

 This is a factory class that takes a TAP::Parser::Source and runs it
 through all the registered TAP::Parser::SourceHandlers to see which one
 should handle the source.

 If you're a plugin author, you'll be interested in how to
 "register_handler"s, how "detect_source" works.

MMEETTHHOODDSS #

CCllaassss MMeetthhooddss _"_n_e_w_"

 Creates a new factory class:

   my $sf = TAP::Parser::IteratorFactory->new( $config );

 $config is optional.  If given, sets "config" and calls "load_handlers".

 _"_r_e_g_i_s_t_e_r___h_a_n_d_l_e_r_"

 Registers a new TAP::Parser::SourceHandler with this factory.

   __PACKAGE__->register_handler( $handler_class );

 _"_h_a_n_d_l_e_r_s_"

 List of handlers that have been registered.

IInnssttaannccee MMeetthhooddss _"_c_o_n_f_i_g_"

  my $cfg = $sf->config;
  $sf->config({ Perl => { %config } });

 Chaining getter/setter for the configuration of the available source
 handlers.  This is a hashref keyed on handler class whose values contain
 config to be passed onto the handlers during detection & creation.  Class
 names may be fully qualified or abbreviated, eg:

   # these are equivalent
   $sf->config({ 'TAP::Parser::SourceHandler::Perl' => { %config } });
   $sf->config({ 'Perl' => { %config } });

 _"_l_o_a_d___h_a_n_d_l_e_r_s_"

  $sf->load_handlers;

 Loads the handler classes defined in "config".  For example, given a
 config:

   $sf->config({
     MySourceHandler => { some => 'config' },
   });

 "load_handlers" will attempt to load the "MySourceHandler" class by
 looking in @INC for it in this order:

   TAP::Parser::SourceHandler::MySourceHandler
   MySourceHandler

 "croak"s on error.

 _"_m_a_k_e___i_t_e_r_a_t_o_r_"

   my $iterator = $src_factory->make_iterator( $source );

 Given a TAP::Parser::Source, finds the most suitable
 TAP::Parser::SourceHandler to use to create a TAP::Parser::Iterator (see
 "detect_source").  Dies on error.

 _"_d_e_t_e_c_t___s_o_u_r_c_e_"

 Given a TAP::Parser::Source, detects what kind of source it is and
 returns _o_n_e TAP::Parser::SourceHandler (the most confident one).  Dies on
 error.

 The detection algorithm works something like this:

   for (@registered_handlers) {
     # ask them how confident they are about handling this source
     $confidence{$handler} = $handler->can_handle( $source )
   }
   # choose the most confident handler

 Ties are handled by choosing the first handler.

SSUUBBCCLLAASSSSIINNGG #

 Please see "SUBCLASSING" in TAP::Parser for a subclassing overview.

EExxaammppllee If we’ve done things right, you’ll probably want to write a new source, rather than sub-classing this (see TAP::Parser::SourceHandler for that).

 But in case you find the need to...

   package MyIteratorFactory;

   use strict;

   use base 'TAP::Parser::IteratorFactory';

   # override source detection algorithm
   sub detect_source {
     my ($self, $raw_source_ref, $meta) = @_;
     # do detective work, using $meta and whatever else...
   }

   1;

AAUUTTHHOORRSS #

 Steve Purkis

AATTTTRRIIBBUUTTIIOONN #

 Originally ripped off from Test::Harness.

 Moved out of TAP::Parser & converted to a factory class to support
 extensible TAP source detective work by Steve Purkis.

SSEEEE AALLSSOO #

 TAP::Object, TAP::Parser, TAP::Parser::SourceHandler,
 TAP::Parser::SourceHandler::File, TAP::Parser::SourceHandler::Perl,
 TAP::Parser::SourceHandler::RawTAP, TAP::Parser::SourceHandler::Handle,
 TAP::Parser::SourceHandler::Executable

perl v5.36.3 2023-02-15 TAP::Parser::IteratorFactory(3p)