MM-6593

merge in changes from CPAN contributor Sebastian Paaske Torholm <spt@jobindex.dk> to add rudimentary support for
pseudo-selectors.

Add tests provided by contributor.

Update manifest

Update changelog

ChangeLog

@@ -48,8 +48,16 @@
 	* Added skipping for '* html' hack sequence frequently used by IE6, should return nothing
 
 0.07	2010-11-02	Kevin Kamel <kamelkev@mailermailer.com>
+
 	* Merge in specificity calculation. This code was ripped out of CSS::Inliner, HTML::Query is a more
 	  appropriate place to do this calculation.
 	* Added optimizations so that the specificity calculation doesn't need a tree in order to operate
 	  nor does it need a prior query to have occurred.
 	* Merge in tests from CSS::Inliner for specificity calculations
+
+0.08	2012-08-01	Kevin Kamel <kamelkev@mailermailer.com>
+	* Added patch from Sebastian Paaske Torholm <spt@jobindex.dk>
+		- Adds support for -child pseudo-classes including proper specificity calculation
+		- Adds tests for verifying specificity calculation and proper selection of -child pseudo classes
+	* Updated documentation with sections for pseudo-classes and psuedo-elements detailing 
+	  current support for those features.

MANIFEST

@@ -10,12 +10,14 @@ t/duplicate.t
 t/element.t
 t/iterative.t
 t/multioperand.t
+t/pseudoclasses.t
 t/query.t
 t/specificity.t
 t/universal.t
 t/html/acidtest.html
 t/html/combinator.html
 t/html/multioperator.html
+t/html/pseudoclasses.html
 t/html/test1.html
 t/html/test2.html
 t/html/test3.html

lib/HTML/Query.pm

@@ -271,6 +271,20 @@ sub query {
                         push( @args, $attribute => qr/.*/ );
                     }
                 }
+                # and/or one or more pseudo-classes
+                if ($query =~ / \G : ([\w\-]+) /cgx) {
+                    my $pseudoclass = $1;
+                    $specificity += 10;
+
+                    if ($pseudoclass eq 'first-child') {
+                        push( @args, sub { ! grep { ref $_ } $_[0]->left() } );
+                    } elsif ($pseudoclass eq 'last-child') {
+                        push( @args, sub { ! grep { ref $_ } $_[0]->right() } );
+                    } else {
+                        warn "Pseudoclass :$pseudoclass not supported";
+                        next;
+                    }
+                }
 
                 # keep going until this particular expression is fully processed
                 last unless scalar(@args) > $work;
@@ -1092,9 +1106,67 @@ with the C<+> character.
 
  @elems = $query->query('img + span')->get_elements();
 
-=head2 Combining Selectors
+=head2 Pseudo-classes
 
-You can combine basic and hierarchical selectors into a single query
+W3C CSS 2 and CSS 3 specifications define new concepts of pseudo-classes to 
+permit formatting based on information that lies outside the document tree. 
+See the following link for the most recent spec:
+L<http://www.w3.org/TR/css3-selectors/#pseudo-classes>
+
+HTML::Query currently has limited support for CSS 2, and no support for CSS 3.
+
+Patches are *highly* encouraged to help add support here.
+
+=head3 -child pseudo-classes
+
+If you want to return child elements within a certain position then -child
+pseudo-classes (:first-child, :last-child) are what you're looking for.
+
+ @elems = $query->query('table td:first-child')->get_elements;
+
+=head3 Link pseudo-classes: :link and :visited
+
+Unsupported.
+
+The :link pseudo-class is to be implemented, currently unsupported.
+
+It is not possible to locate :visited outside of a browser context due to it's
+dynamic nature.
+
+=head3 Dynamic pseudo-classes
+
+Unsupported.
+
+It is not possible to locate these classes(:hover, :active, :focus) outside
+of a browser context due to their dynamic nature.
+
+=head3 Language pseudo-class
+
+Unsupported.
+
+Functionality for the :lang psuedo-class is largely replicated by using an 
+attribute selector for lang combined with a universal selector query.
+
+If this is insufficient I'd love to see a patch adding support for it.
+
+=head3 Other pseudo-classes
+
+W3C CSS 3 added a number of new behaviors that need support. At
+this time there is no support for them, but we should work on adding support.
+
+Patches are very welcome.
+
+=head2 Pseudo-elements
+
+W3C CSS 2 and CSS 3 specification defines new concepts of pseudo-elements to
+permit formatting based on information that lies outside the document tree.
+See the following link for the most recent spec:
+L<http://www.w3.org/TR/css3-selectors/#pseudo-elements>
+
+At this time there is no support for pseudo-elements, but we are working
+on adding support.
+
+Patches are very welcome.
 
 =head2 Combining Selectors
 

t/html/pseudoclasses.html

@@ -0,0 +1,24 @@
+<html>
+    <head>
+      <script type="text/javascript" src="/utilities/smush.bin?scripts=swfobject.js,jquery/jquery-1.7.2.min.js,general.js"></script>
+    </head>
+    <body>
+        <table>
+            <tr>
+                <td>1,1</td>
+                <td>1,2</td>
+                <td>1,3</td>
+            </tr>
+            <tr>
+                <td>2,1</td>
+                <td>2,2</td>
+                <td>2,3</td>
+            </tr>
+            <tr>
+                <td>3,1</td>
+                <td>3,2</td>
+                <td>3,3</td>
+            </tr>
+        </table>
+     </body>
+</html>

t/pseudoclasses.t

@@ -0,0 +1,42 @@
+use strict;
+use warnings;
+use lib qw( ./lib ../lib );
+use HTML::TreeBuilder;
+use Badger::Filesystem '$Bin Dir';
+use Badger::Test
+    tests => 10,
+    debug => 'HTML::Query',
+    args  => \@ARGV;
+
+use HTML::Query 'Query';
+
+our $Query    = 'HTML::Query';
+our $Builder  = 'HTML::TreeBuilder';
+our $test_dir = Dir($Bin);
+our $html_dir = $test_dir->dir('html')->must_exist;
+our $pseudo  = $html_dir->file('pseudoclasses.html')->must_exist;
+
+my ($query, $tree);
+
+$tree = $Builder->new;
+$tree->parse_file( $pseudo->absolute );
+
+ok( $tree, 'parsed tree for test file: ' . $pseudo->name );
+$query = Query $tree;
+ok( $query, 'created query' );
+
+my $test1 = $query->query('table td:first-child');
+is( $test1->size, 3, 'test1 - size' );
+is( join(" | ", $test1->as_trimmed_text), "1,1 | 2,1 | 3,1", 'test1 - text');
+
+my $test2 = $query->query('table td:last-child');
+is( $test2->size, 3, 'test2 - size' );
+is( join(" | ", $test2->as_trimmed_text), "1,3 | 2,3 | 3,3", 'test2 - text');
+
+my $test3 = $query->query('table tr:first-child td');
+is( $test3->size, 3, 'test3 - size' );
+is( join(" | ", $test3->as_trimmed_text), "1,1 | 1,2 | 1,3", 'test3 - text');
+
+my $test4 = $query->query('table tr:last-child td');
+is( $test4->size, 3, 'test4 - size' );
+is( join(" | ", $test4->as_trimmed_text), "3,1 | 3,2 | 3,3", 'test4 - text');

t/specificity.t

@@ -14,7 +14,7 @@ use warnings;
 use lib qw( ./lib ../lib );
 use Badger::Filesystem '$Bin Dir';
 use Badger::Test
-    tests => 23,
+    tests => 24,
     debug => 'HTML::Query',
     args  => \@ARGV;
 
@@ -44,7 +44,8 @@ my %rules = (
     "*" => 0,
     "div#id-one div p>em" => 104,
     "html#simple body#internal" => 202,
-    "body#internal" => 101
+    "body#internal" => 101,
+    "div:first-child" => 11,
 );
 
 foreach my $rule (keys %rules) {