Thanks to visit codestin.com
Credit goes to perldoc.perl.org

You are viewing the version of this documentation from Perl blead. This is the main development branch of Perl. (git commit 8785c114b5d618cb4ac8a6ffd5f41eff9c585810)

CONTENTS

NAME

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

VERSION

Version 3.52

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

croaks 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