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WWW::Mechanize::TreeBuilder - combine WWW::Mechanize and HTML::TreeBuilder in nice ways


 use Test::More tests => 2;
 use Test::WWW::Mechanize;
 use WWW::Mechanize::TreeBuilder;
 # or 
 # use WWW::Mechanize;
 # or 
 # use Test::WWW::Mechanize::Catalyst 'MyApp';

 my $mech = Test::WWW::Mechanize->new;
 # or
 #my $mech = Test::WWW::Mechanize::Catalyst->new;
 # etc. etc.

 is( $mech->look_down(_tag => 'p')->as_trimmed_text, 'Some text', 'It worked' );


This module combines WWW::Mechanize and HTML::TreeBuilder. Why? Because I've seen too much code like the following:

 like($mech->content, qr{<p>some text</p>}, "Found the right tag");

Which is just all flavours of wrong - its akin to processing XML with regexps. Instead, do it like the following:

 ok($mech->look_down(_tag => 'p', sub { $_[0]->as_trimmed_text eq 'some text' })

The anon-sub there is a bit icky, but this means that anyone should happen to add attributes to the <p> tag (such as an id or a class) it will still work and find the right tag.

All of the methods available on HTML::Element (that aren't 'private' - i.e. that don't begin with an underscore) such as look_down or find are automatically delegated to $mech->tree through the magic of Moose.


Everything in WWW::Mechanize (or which ever sub class you apply it to) and all public methods from HTML::Element except those where WWW::Mechanize and HTML::Element overlap. In the case where the two classes both define a method, the one from WWW::Mechanize will be used (so that the existing behaviour of Mechanize doesn't break.)


HTML::TreeBuilder::XPath allows you to use xpath selectors to select elements in the tree. You can use that module by providing parameters to the moose role:

 with 'WWW::Mechanize::TreeBuilder' => {
   tree_class => 'HTML::TreeBuilder::XPath'

 # or
 # NOTE: No hashref using this method
   tree_class => 'HTML::TreeBuilder::XPath';

and class will be automatically loaded for you. This class will be used to construct the tree in the following manner:

 $tree = $tree_class->new_from_content($req->decoded_content)->elementify;

You can also specify a element_class parameter which is the (HTML::Element sub)class that methods are proxied from. This module provides defaults for element_class when tree_class is "HTML::TreeBuilder" or "HTML::TreeBuilder::XPath" - it will warn otherwise.


Ash Berlin <>


Same as Perl 5.8, or at your option any later version of Perl.