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


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

VERSION
       Version 3.44

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

DESCRIPTION
       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.

METHODS
   Class Methods
       "new"

       Creates a new factory class:

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

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

       "register_handler"

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

         __PACKAGE__->register_handler( $handler_class );

       "handlers"

       List of handlers that have been registered.

   Instance Methods
       "config"

        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 } });

       "load_handlers"

        $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.

       "make_iterator"

         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.

       "detect_source"

       Given a TAP::Parser::Source, detects what kind of source it is and
       returns one 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.

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

   Example
       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;

AUTHORS
       Steve Purkis

ATTRIBUTION
       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.

SEE ALSO
       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 v5.38.2                      2024-02-11
                                           TAP::Parser::IteratorFactory(3perl)