From f6319ed0c7507b1bba1f1f02a1f73fda9808b2f7 Mon Sep 17 00:00:00 2001
From: Yorick Peterse <yorickpeterse@gmail.com>
Date: Tue, 4 Nov 2014 23:25:44 +0100
Subject: [PATCH] Added failing descendant-or-self XPath specs.

These currently fail due to the child:: selector not working entirely as it
should be. Consider the following XML:

    <a><b><b><c class="x"></c></b></b></a>

And the following XPath:

    descendant-or-self::node()/a

In Nokogiri/libxml this will return a node set containing the <a> node. In Oga
however this will return an empty node set. This will require some further
investigation to see what exactly is going on, and in particular what is the
correct behaviour.
---
 .../evaluator/axes/descendant_or_self_spec.rb | 58 +++++++++++++++++++
 1 file changed, 58 insertions(+)

diff --git a/spec/oga/xpath/evaluator/axes/descendant_or_self_spec.rb b/spec/oga/xpath/evaluator/axes/descendant_or_self_spec.rb
index 081c988..5b9f8ca 100644
--- a/spec/oga/xpath/evaluator/axes/descendant_or_self_spec.rb
+++ b/spec/oga/xpath/evaluator/axes/descendant_or_self_spec.rb
@@ -40,6 +40,32 @@ describe Oga::XPath::Evaluator do
       end
     end
 
+    context 'chained descendants' do
+      before do
+        @set = @evaluator.evaluate(
+          'descendant-or-self::a/descendant-or-self::*'
+        )
+      end
+
+      it_behaves_like :node_set, :length => 4
+
+      example 'return the <a> node' do
+        @set[0].should == @first_a
+      end
+
+      example 'return the first <b> node' do
+        @set[1].should == @first_b
+      end
+
+      example 'return the second <b> node' do
+        @set[2].should == @second_b
+      end
+
+      example 'return the <c> node' do
+        @set[3].should == @first_c
+      end
+    end
+
     context 'nested descendants with a matching predicate' do
       before do
         @set = @evaluator.evaluate('descendant-or-self::c[@class="x"]')
@@ -139,5 +165,37 @@ describe Oga::XPath::Evaluator do
         @set[0].should == @first_c
       end
     end
+
+    context 'descendants of descendants usign the short form' do
+      before do
+        @set = @evaluator.evaluate('//a//*')
+      end
+
+      it_behaves_like :node_set, :length => 3
+
+      example 'return the first <b> node' do
+        @set[0].should == @first_b
+      end
+
+      example 'return the second <b> node' do
+        @set[1].should == @second_b
+      end
+
+      example 'return the <c> node' do
+        @set[2].should == @first_c
+      end
+    end
+
+    context 'children of descendants using the short form' do
+      before do
+        @set = @evaluator.evaluate('//a/b')
+      end
+
+      it_behaves_like :node_set, :length => 1
+
+      example 'return the first <b> node' do
+        @set[0].should == @first_b
+      end
+    end
   end
 end