Specs for various XPath::Evaluator helper methods.

lib/oga/xml/node.rb

@@ -49,12 +49,13 @@ module Oga
       end
 
       ##
-      # Returns the parent node of the current node.
+      # Returns the parent node of the current node. If there is no parent node
+      # `nil` is returned instead.
       #
       # @return [Oga::XML::Node]
       #
       def parent
-        return node_set.owner
+        return node_set ? node_set.owner : nil
       end
 
       ##

spec/oga/xml/node_spec.rb

@@ -57,6 +57,10 @@ describe Oga::XML::Node do
 
       node.parent.should == owner
     end
+
+    example 'return nil if there is no parent node' do
+      described_class.new.parent.nil?.should == true
+    end
   end
 
   context '#previous' do

spec/oga/xpath/evaluator/general_spec.rb

@@ -0,0 +1,96 @@
+require 'spec_helper'
+
+describe Oga::XPath::Evaluator do
+  before do
+    @document  = parse('<a>Hello</a>')
+    @evaluator = described_class.new(@document)
+  end
+
+  context '#child_nodes' do
+    before do
+      @children = Oga::XML::NodeSet.new([
+        Oga::XML::Element.new(:name => 'b'),
+        Oga::XML::Element.new(:name => 'b')
+      ])
+
+      @parent = Oga::XML::Element.new(:name => 'a', :children => @children)
+    end
+
+    example "return a node's child nodes" do
+      nodes = @evaluator.child_nodes([@parent])
+
+      nodes[0].should == @children[0]
+      nodes[1].should == @children[1]
+    end
+  end
+
+  context '#node_matches?' do
+    before do
+      @name_node    = Oga::XML::Element.new(:name => 'a')
+      @name_ns_node = Oga::XML::Element.new(:name => 'b', :namespace => 'x')
+    end
+
+    example 'return true if a node is matched by its name' do
+      @evaluator.node_matches?(@name_node, s(:test, nil, 'a')).should == true
+    end
+
+    example 'return true if a node is matched by a wildcard name' do
+      @evaluator.node_matches?(@name_node, s(:test, nil, '*')).should == true
+    end
+
+    example 'return false if a node is not matched by its name' do
+      @evaluator.node_matches?(@name_node, s(:test, nil, 'foo')).should == false
+    end
+
+    example 'return true if a node is matched by its name and namespace' do
+      @evaluator.node_matches?(@name_ns_node, s(:test, 'x', 'b')).should == true
+    end
+
+    example 'return false if a node is not matched by its namespace' do
+      @evaluator.node_matches?(@name_ns_node, s(:test, 'y', 'b')).should == false
+    end
+
+    example 'return true if a node is matched by a wildcard namespace' do
+      @evaluator.node_matches?(@name_ns_node, s(:test, '*', 'b')).should == true
+    end
+
+    example 'return true if a node is matched by a full wildcard search' do
+      @evaluator.node_matches?(@name_ns_node, s(:test, '*', '*')).should == true
+    end
+
+    example 'return true if a node is matched without having a namespace' do
+      @evaluator.node_matches?(@name_node, s(:test, '*', 'a')).should == true
+    end
+  end
+
+  context '#can_match_node?' do
+    example 'return true for an XML::Element instance' do
+      @evaluator.can_match_node?(Oga::XML::Element.new).should == true
+    end
+
+    example 'return true for an XML::Attribute instance' do
+      @evaluator.can_match_node?(Oga::XML::Attribute.new).should == true
+    end
+
+    example 'return false for an XML::Text instance' do
+      @evaluator.can_match_node?(Oga::XML::Text.new).should == false
+    end
+  end
+
+  context '#has_parent?' do
+    before do
+      @parent = Oga::XML::Element.new
+      @child  = Oga::XML::Element.new
+
+      set = Oga::XML::NodeSet.new([@child], @parent)
+    end
+
+    example 'return true if a node has a parent node' do
+      @evaluator.has_parent?(@child).should == true
+    end
+
+    example 'return false if a node has no parent node' do
+      @evaluator.has_parent?(@parent).should == false
+    end
+  end
+end