oga/lib/oga/xml/node.rb

132 lines
3.0 KiB
Ruby

module Oga
module XML
##
# A generic XML node. Instances of this class can belong to a
# {Oga::XML::NodeSet} and can be used to query surrounding and parent
# nodes.
#
# @!attribute [rw] node_set
# @return [Oga::XML::NodeSet]
#
class Node
attr_accessor :node_set
##
# @param [Hash] options
#
# @option options [Oga::XML::NodeSet] :node_set The node set that this
# node belongs to.
#
# @option options [Oga::XML::NodeSet|Array] :children The child nodes of
# the current node.
#
def initialize(options = {})
@node_set = options[:node_set]
self.children = options[:children] if options[:children]
end
##
# Returns the child nodes of the current node.
#
# @return [Oga::XML::NodeSet]
#
def children
return @children ||= NodeSet.new([], self)
end
##
# Sets the child nodes of the element.
#
# @param [Oga::XML::NodeSet|Array] nodes
#
def children=(nodes)
if nodes.is_a?(NodeSet)
@children = nodes
else
@children = NodeSet.new(nodes, self)
end
end
##
# Returns the parent node of the current node.
#
# @return [Oga::XML::Node]
#
def parent
return node_set.owner
end
##
# Returns the preceding node, or nil if there is none.
#
# @return [Oga::XML::Node]
#
def previous
index = node_set.index(self) - 1
return index >= 0 ? node_set[index] : nil
end
##
# Returns the following node, or nil if there is none.
#
# @return [Oga::XML::Node]
#
def next
index = node_set.index(self) + 1
length = node_set.length
return index <= length ? node_set[index] : nil
end
##
# Returns the root document/node of the current node. The node is
# retrieved by traversing upwards in the DOM tree from the current node.
#
# @return [Oga::XML::Document|Oga::XML::Node]
#
def root_node
node = self
loop do
if !node.is_a?(Document) and node.node_set
node = node.node_set.owner
else
break
end
end
return node
end
##
# Generates the inspect value for the current node. Sub classes can
# overwrite the {#extra_inspect_data} method to customize the output
# format.
#
# @param [Fixnum] indent
# @return [String]
#
def inspect(indent = 0)
class_name = self.class.to_s.split('::').last
spacing = ' ' * indent
return "#{spacing}#{class_name}(#{extra_inspect_data(indent)})"
end
##
# @return [String]
#
def extra_inspect_data; end
##
# @return [Symbol]
#
def node_type
return :node
end
end # Element
end # XML
end # Oga