Module: Nori::Parser::REXML

Defined in:
lib/nori/parser/rexml.rb

Overview

Nori::Parser::REXML

REXML pull parser.

Class Method Summary collapse

Class Method Details

.parse(xml, options) ⇒ Object 



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# File 'lib/nori/parser/rexml.rb', line 13

def self.parse(xml, options)
  stack = []
  # Tracks the xml:space value in effect for each open element so
  # whitespace-only text can be kept under xml:space="preserve".
  space_stack = []
  parser = ::REXML::Parsers::BaseParser.new(xml)

  while true
    raw_data = parser.pull
    event = unnormalize(raw_data)
    case event[0]
    when :end_document
      break
    when :end_doctype, :start_doctype
      # do nothing
    when :start_element
      space_stack.push xml_space(event[2], space_stack)
      stack.push Nori::XMLUtilityNode.new(options, event[1], event[2])
    when :end_element
      space_stack.pop
      if stack.size > 1
        temp = stack.pop
        stack.last.add_node(temp)
      end
    when :text
      # Whitespace-only text is insignificant and stripped, unless
      # xml:space="preserve" is in effect under the :standards profile.
      keep = preserve_whitespace?(options, space_stack) || event[1].strip.length > 0
      stack.last.add_node(event[1]) if keep && !stack.empty?
    when :cdata
      # CDATA is the author's explicit literal-data marker (XML 1.0 §2.7),
      # so whitespace-only CDATA is kept rather than stripped like text.
      stack.last.add_node(raw_data[1]) unless stack.empty?
    end
  end
  stack.length > 0 ? stack.pop.to_hash : {}
end

.preserve_whitespace?(options, space_stack) ⇒ Boolean

Whether whitespace-only text must be kept for the current element. Only the :standards profile honors xml:space.

Returns:

  • (Boolean) 


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# File 'lib/nori/parser/rexml.rb', line 66

def self.preserve_whitespace?(options, space_stack)
  options[:standards] && space_stack.last == "preserve"
end

.unnormalize(event) ⇒ Object 



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# File 'lib/nori/parser/rexml.rb', line 70

def self.unnormalize(event)
  event.map do |el|
    if el.is_a?(String)
      ::REXML::Text.unnormalize(el)
    elsif el.is_a?(Hash)
      el.each {|k,v| el[k] = ::REXML::Text.unnormalize(v)}
    else
      el
    end
  end
end

.xml_space(attributes, space_stack) ⇒ String

The xml:space value for an element: its own declaration if it has one, otherwise the value inherited from the nearest ancestor. Defaults to "default". See XML 1.0 §2.10.

Parameters:

  • attributes (Hash{String => String}) —

    the element's attributes

  • space_stack (Array<String>) —

    the ancestor xml:space values

Returns:

  • (String) —

    "preserve", "default", or an inherited value



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# File 'lib/nori/parser/rexml.rb', line 58

def self.xml_space(attributes, space_stack)
  (attributes && attributes["xml:space"]) || space_stack.last || "default"
end