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ruby--ruby/lib/rexml/element.rb
Kouhei Sutou 0f18bc7fca [ruby/rexml] Fix attribute's default namespace behavior
NOTE: It's a backward incompatible change. If we have any serious
problems with this change, we may revert this change.

The XML namespace specification says the default namespace doesn't
apply to attribute names but it does in REXML without this change:

https://www.w3.org/TR/xml-names/#uniqAttrs

> the default namespace does not apply to attribute names

REXML reports a parse error for the following XML that is described as
a valid XML in the XML nsmaspace specification without this change:

    <!-- http://www.w3.org is bound to n1 and is the default -->
    <x xmlns:n1="http://www.w3.org"
       xmlns="http://www.w3.org" >
      <good a="1"     b="2" />
      <good a="1"     n1:a="2" />
    </x>

If attribute doesn't have prefix, the attribute should return "" for
both #prefix and #namespace.

https://github.com/ruby/rexml/commit/9e4fd552bc
2019-08-04 11:54:27 +09:00

1269 lines
44 KiB
Ruby

# frozen_string_literal: false
require_relative "parent"
require_relative "namespace"
require_relative "attribute"
require_relative "cdata"
require_relative "xpath"
require_relative "parseexception"
module REXML
# An implementation note about namespaces:
# As we parse, when we find namespaces we put them in a hash and assign
# them a unique ID. We then convert the namespace prefix for the node
# to the unique ID. This makes namespace lookup much faster for the
# cost of extra memory use. We save the namespace prefix for the
# context node and convert it back when we write it.
@@namespaces = {}
# Represents a tagged XML element. Elements are characterized by
# having children, attributes, and names, and can themselves be
# children.
class Element < Parent
include Namespace
UNDEFINED = "UNDEFINED"; # The default name
# Mechanisms for accessing attributes and child elements of this
# element.
attr_reader :attributes, :elements
# The context holds information about the processing environment, such as
# whitespace handling.
attr_accessor :context
# Constructor
# arg::
# if not supplied, will be set to the default value.
# If a String, the name of this object will be set to the argument.
# If an Element, the object will be shallowly cloned; name,
# attributes, and namespaces will be copied. Children will +not+ be
# copied.
# parent::
# if supplied, must be a Parent, and will be used as
# the parent of this object.
# context::
# If supplied, must be a hash containing context items. Context items
# include:
# * <tt>:respect_whitespace</tt> the value of this is :+all+ or an array of
# strings being the names of the elements to respect
# whitespace for. Defaults to :+all+.
# * <tt>:compress_whitespace</tt> the value can be :+all+ or an array of
# strings being the names of the elements to ignore whitespace on.
# Overrides :+respect_whitespace+.
# * <tt>:ignore_whitespace_nodes</tt> the value can be :+all+ or an array
# of strings being the names of the elements in which to ignore
# whitespace-only nodes. If this is set, Text nodes which contain only
# whitespace will not be added to the document tree.
# * <tt>:raw</tt> can be :+all+, or an array of strings being the names of
# the elements to process in raw mode. In raw mode, special
# characters in text is not converted to or from entities.
def initialize( arg = UNDEFINED, parent=nil, context=nil )
super(parent)
@elements = Elements.new(self)
@attributes = Attributes.new(self)
@context = context
if arg.kind_of? String
self.name = arg
elsif arg.kind_of? Element
self.name = arg.expanded_name
arg.attributes.each_attribute{ |attribute|
@attributes << Attribute.new( attribute )
}
@context = arg.context
end
end
def inspect
rv = "<#@expanded_name"
@attributes.each_attribute do |attr|
rv << " "
attr.write( rv, 0 )
end
if children.size > 0
rv << "> ... </>"
else
rv << "/>"
end
end
# Creates a shallow copy of self.
# d = Document.new "<a><b/><b/><c><d/></c></a>"
# new_a = d.root.clone
# puts new_a # => "<a/>"
def clone
self.class.new self
end
# Evaluates to the root node of the document that this element
# belongs to. If this element doesn't belong to a document, but does
# belong to another Element, the parent's root will be returned, until the
# earliest ancestor is found.
#
# Note that this is not the same as the document element.
# In the following example, <a> is the document element, and the root
# node is the parent node of the document element. You may ask yourself
# why the root node is useful: consider the doctype and XML declaration,
# and any processing instructions before the document element... they
# are children of the root node, or siblings of the document element.
# The only time this isn't true is when an Element is created that is
# not part of any Document. In this case, the ancestor that has no
# parent acts as the root node.
# d = Document.new '<a><b><c/></b></a>'
# a = d[1] ; c = a[1][1]
# d.root_node == d # TRUE
# a.root_node # namely, d
# c.root_node # again, d
def root_node
parent.nil? ? self : parent.root_node
end
def root
return elements[1] if self.kind_of? Document
return self if parent.kind_of? Document or parent.nil?
return parent.root
end
# Evaluates to the document to which this element belongs, or nil if this
# element doesn't belong to a document.
def document
rt = root
rt.parent if rt
end
# Evaluates to +true+ if whitespace is respected for this element. This
# is the case if:
# 1. Neither :+respect_whitespace+ nor :+compress_whitespace+ has any value
# 2. The context has :+respect_whitespace+ set to :+all+ or
# an array containing the name of this element, and
# :+compress_whitespace+ isn't set to :+all+ or an array containing the
# name of this element.
# The evaluation is tested against +expanded_name+, and so is namespace
# sensitive.
def whitespace
@whitespace = nil
if @context
if @context[:respect_whitespace]
@whitespace = (@context[:respect_whitespace] == :all or
@context[:respect_whitespace].include? expanded_name)
end
@whitespace = false if (@context[:compress_whitespace] and
(@context[:compress_whitespace] == :all or
@context[:compress_whitespace].include? expanded_name)
)
end
@whitespace = true unless @whitespace == false
@whitespace
end
def ignore_whitespace_nodes
@ignore_whitespace_nodes = false
if @context
if @context[:ignore_whitespace_nodes]
@ignore_whitespace_nodes =
(@context[:ignore_whitespace_nodes] == :all or
@context[:ignore_whitespace_nodes].include? expanded_name)
end
end
end
# Evaluates to +true+ if raw mode is set for this element. This
# is the case if the context has :+raw+ set to :+all+ or
# an array containing the name of this element.
#
# The evaluation is tested against +expanded_name+, and so is namespace
# sensitive.
def raw
@raw = (@context and @context[:raw] and
(@context[:raw] == :all or
@context[:raw].include? expanded_name))
@raw
end
#once :whitespace, :raw, :ignore_whitespace_nodes
#################################################
# Namespaces #
#################################################
# Evaluates to an +Array+ containing the prefixes (names) of all defined
# namespaces at this context node.
# doc = Document.new("<a xmlns:x='1' xmlns:y='2'><b/><c xmlns:z='3'/></a>")
# doc.elements['//b'].prefixes # -> ['x', 'y']
def prefixes
prefixes = []
prefixes = parent.prefixes if parent
prefixes |= attributes.prefixes
return prefixes
end
def namespaces
namespaces = {}
namespaces = parent.namespaces if parent
namespaces = namespaces.merge( attributes.namespaces )
return namespaces
end
# Evaluates to the URI for a prefix, or the empty string if no such
# namespace is declared for this element. Evaluates recursively for
# ancestors. Returns the default namespace, if there is one.
# prefix::
# the prefix to search for. If not supplied, returns the default
# namespace if one exists
# Returns::
# the namespace URI as a String, or nil if no such namespace
# exists. If the namespace is undefined, returns an empty string
# doc = Document.new("<a xmlns='1' xmlns:y='2'><b/><c xmlns:z='3'/></a>")
# b = doc.elements['//b']
# b.namespace # -> '1'
# b.namespace("y") # -> '2'
def namespace(prefix=nil)
if prefix.nil?
prefix = prefix()
end
if prefix == ''
prefix = "xmlns"
else
prefix = "xmlns:#{prefix}" unless prefix[0,5] == 'xmlns'
end
ns = attributes[ prefix ]
ns = parent.namespace(prefix) if ns.nil? and parent
ns = '' if ns.nil? and prefix == 'xmlns'
return ns
end
# Adds a namespace to this element.
# prefix::
# the prefix string, or the namespace URI if +uri+ is not
# supplied
# uri::
# the namespace URI. May be nil, in which +prefix+ is used as
# the URI
# Evaluates to: this Element
# a = Element.new("a")
# a.add_namespace("xmlns:foo", "bar" )
# a.add_namespace("foo", "bar") # shorthand for previous line
# a.add_namespace("twiddle")
# puts a #-> <a xmlns:foo='bar' xmlns='twiddle'/>
def add_namespace( prefix, uri=nil )
unless uri
@attributes["xmlns"] = prefix
else
prefix = "xmlns:#{prefix}" unless prefix =~ /^xmlns:/
@attributes[ prefix ] = uri
end
self
end
# Removes a namespace from this node. This only works if the namespace is
# actually declared in this node. If no argument is passed, deletes the
# default namespace.
#
# Evaluates to: this element
# doc = Document.new "<a xmlns:foo='bar' xmlns='twiddle'/>"
# doc.root.delete_namespace
# puts doc # -> <a xmlns:foo='bar'/>
# doc.root.delete_namespace 'foo'
# puts doc # -> <a/>
def delete_namespace namespace="xmlns"
namespace = "xmlns:#{namespace}" unless namespace == 'xmlns'
attribute = attributes.get_attribute(namespace)
attribute.remove unless attribute.nil?
self
end
#################################################
# Elements #
#################################################
# Adds a child to this element, optionally setting attributes in
# the element.
# element::
# optional. If Element, the element is added.
# Otherwise, a new Element is constructed with the argument (see
# Element.initialize).
# attrs::
# If supplied, must be a Hash containing String name,value
# pairs, which will be used to set the attributes of the new Element.
# Returns:: the Element that was added
# el = doc.add_element 'my-tag'
# el = doc.add_element 'my-tag', {'attr1'=>'val1', 'attr2'=>'val2'}
# el = Element.new 'my-tag'
# doc.add_element el
def add_element element, attrs=nil
raise "First argument must be either an element name, or an Element object" if element.nil?
el = @elements.add(element)
attrs.each do |key, value|
el.attributes[key]=value
end if attrs.kind_of? Hash
el
end
# Deletes a child element.
# element::
# Must be an +Element+, +String+, or +Integer+. If Element,
# the element is removed. If String, the element is found (via XPath)
# and removed. <em>This means that any parent can remove any
# descendant.<em> If Integer, the Element indexed by that number will be
# removed.
# Returns:: the element that was removed.
# doc.delete_element "/a/b/c[@id='4']"
# doc.delete_element doc.elements["//k"]
# doc.delete_element 1
def delete_element element
@elements.delete element
end
# Evaluates to +true+ if this element has at least one child Element
# doc = Document.new "<a><b/><c>Text</c></a>"
# doc.root.has_elements # -> true
# doc.elements["/a/b"].has_elements # -> false
# doc.elements["/a/c"].has_elements # -> false
def has_elements?
!@elements.empty?
end
# Iterates through the child elements, yielding for each Element that
# has a particular attribute set.
# key::
# the name of the attribute to search for
# value::
# the value of the attribute
# max::
# (optional) causes this method to return after yielding
# for this number of matching children
# name::
# (optional) if supplied, this is an XPath that filters
# the children to check.
#
# doc = Document.new "<a><b @id='1'/><c @id='2'/><d @id='1'/><e/></a>"
# # Yields b, c, d
# doc.root.each_element_with_attribute( 'id' ) {|e| p e}
# # Yields b, d
# doc.root.each_element_with_attribute( 'id', '1' ) {|e| p e}
# # Yields b
# doc.root.each_element_with_attribute( 'id', '1', 1 ) {|e| p e}
# # Yields d
# doc.root.each_element_with_attribute( 'id', '1', 0, 'd' ) {|e| p e}
def each_element_with_attribute( key, value=nil, max=0, name=nil, &block ) # :yields: Element
each_with_something( proc {|child|
if value.nil?
child.attributes[key] != nil
else
child.attributes[key]==value
end
}, max, name, &block )
end
# Iterates through the children, yielding for each Element that
# has a particular text set.
# text::
# the text to search for. If nil, or not supplied, will iterate
# over all +Element+ children that contain at least one +Text+ node.
# max::
# (optional) causes this method to return after yielding
# for this number of matching children
# name::
# (optional) if supplied, this is an XPath that filters
# the children to check.
#
# doc = Document.new '<a><b>b</b><c>b</c><d>d</d><e/></a>'
# # Yields b, c, d
# doc.each_element_with_text {|e|p e}
# # Yields b, c
# doc.each_element_with_text('b'){|e|p e}
# # Yields b
# doc.each_element_with_text('b', 1){|e|p e}
# # Yields d
# doc.each_element_with_text(nil, 0, 'd'){|e|p e}
def each_element_with_text( text=nil, max=0, name=nil, &block ) # :yields: Element
each_with_something( proc {|child|
if text.nil?
child.has_text?
else
child.text == text
end
}, max, name, &block )
end
# Synonym for Element.elements.each
def each_element( xpath=nil, &block ) # :yields: Element
@elements.each( xpath, &block )
end
# Synonym for Element.to_a
# This is a little slower than calling elements.each directly.
# xpath:: any XPath by which to search for elements in the tree
# Returns:: an array of Elements that match the supplied path
def get_elements( xpath )
@elements.to_a( xpath )
end
# Returns the next sibling that is an element, or nil if there is
# no Element sibling after this one
# doc = Document.new '<a><b/>text<c/></a>'
# doc.root.elements['b'].next_element #-> <c/>
# doc.root.elements['c'].next_element #-> nil
def next_element
element = next_sibling
element = element.next_sibling until element.nil? or element.kind_of? Element
return element
end
# Returns the previous sibling that is an element, or nil if there is
# no Element sibling prior to this one
# doc = Document.new '<a><b/>text<c/></a>'
# doc.root.elements['c'].previous_element #-> <b/>
# doc.root.elements['b'].previous_element #-> nil
def previous_element
element = previous_sibling
element = element.previous_sibling until element.nil? or element.kind_of? Element
return element
end
#################################################
# Text #
#################################################
# Evaluates to +true+ if this element has at least one Text child
def has_text?
not text().nil?
end
# A convenience method which returns the String value of the _first_
# child text element, if one exists, and +nil+ otherwise.
#
# <em>Note that an element may have multiple Text elements, perhaps
# separated by other children</em>. Be aware that this method only returns
# the first Text node.
#
# This method returns the +value+ of the first text child node, which
# ignores the +raw+ setting, so always returns normalized text. See
# the Text::value documentation.
#
# doc = Document.new "<p>some text <b>this is bold!</b> more text</p>"
# # The element 'p' has two text elements, "some text " and " more text".
# doc.root.text #-> "some text "
def text( path = nil )
rv = get_text(path)
return rv.value unless rv.nil?
nil
end
# Returns the first child Text node, if any, or +nil+ otherwise.
# This method returns the actual +Text+ node, rather than the String content.
# doc = Document.new "<p>some text <b>this is bold!</b> more text</p>"
# # The element 'p' has two text elements, "some text " and " more text".
# doc.root.get_text.value #-> "some text "
def get_text path = nil
rv = nil
if path
element = @elements[ path ]
rv = element.get_text unless element.nil?
else
rv = @children.find { |node| node.kind_of? Text }
end
return rv
end
# Sets the first Text child of this object. See text() for a
# discussion about Text children.
#
# If a Text child already exists, the child is replaced by this
# content. This means that Text content can be deleted by calling
# this method with a nil argument. In this case, the next Text
# child becomes the first Text child. In no case is the order of
# any siblings disturbed.
# text::
# If a String, a new Text child is created and added to
# this Element as the first Text child. If Text, the text is set
# as the first Child element. If nil, then any existing first Text
# child is removed.
# Returns:: this Element.
# doc = Document.new '<a><b/></a>'
# doc.root.text = 'Sean' #-> '<a><b/>Sean</a>'
# doc.root.text = 'Elliott' #-> '<a><b/>Elliott</a>'
# doc.root.add_element 'c' #-> '<a><b/>Elliott<c/></a>'
# doc.root.text = 'Russell' #-> '<a><b/>Russell<c/></a>'
# doc.root.text = nil #-> '<a><b/><c/></a>'
def text=( text )
if text.kind_of? String
text = Text.new( text, whitespace(), nil, raw() )
elsif !text.nil? and !text.kind_of? Text
text = Text.new( text.to_s, whitespace(), nil, raw() )
end
old_text = get_text
if text.nil?
old_text.remove unless old_text.nil?
else
if old_text.nil?
self << text
else
old_text.replace_with( text )
end
end
return self
end
# A helper method to add a Text child. Actual Text instances can
# be added with regular Parent methods, such as add() and <<()
# text::
# if a String, a new Text instance is created and added
# to the parent. If Text, the object is added directly.
# Returns:: this Element
# e = Element.new('a') #-> <e/>
# e.add_text 'foo' #-> <e>foo</e>
# e.add_text Text.new(' bar') #-> <e>foo bar</e>
# Note that at the end of this example, the branch has <b>3</b> nodes; the 'e'
# element and <b>2</b> Text node children.
def add_text( text )
if text.kind_of? String
if @children[-1].kind_of? Text
@children[-1] << text
return
end
text = Text.new( text, whitespace(), nil, raw() )
end
self << text unless text.nil?
return self
end
def node_type
:element
end
def xpath
path_elements = []
cur = self
path_elements << __to_xpath_helper( self )
while cur.parent
cur = cur.parent
path_elements << __to_xpath_helper( cur )
end
return path_elements.reverse.join( "/" )
end
#################################################
# Attributes #
#################################################
# Fetches an attribute value or a child.
#
# If String or Symbol is specified, it's treated as attribute
# name. Attribute value as String or +nil+ is returned. This case
# is shortcut of +attributes[name]+.
#
# If Integer is specified, it's treated as the index of
# child. It returns Nth child.
#
# doc = REXML::Document.new("<a attr='1'><b/><c/></a>")
# doc.root["attr"] # => "1"
# doc.root.attributes["attr"] # => "1"
# doc.root[1] # => <c/>
def [](name_or_index)
case name_or_index
when String
attributes[name_or_index]
when Symbol
attributes[name_or_index.to_s]
else
super
end
end
def attribute( name, namespace=nil )
prefix = nil
if namespaces.respond_to? :key
prefix = namespaces.key(namespace) if namespace
else
prefix = namespaces.index(namespace) if namespace
end
prefix = nil if prefix == 'xmlns'
ret_val =
attributes.get_attribute( "#{prefix ? prefix + ':' : ''}#{name}" )
return ret_val unless ret_val.nil?
return nil if prefix.nil?
# now check that prefix'es namespace is not the same as the
# default namespace
return nil unless ( namespaces[ prefix ] == namespaces[ 'xmlns' ] )
attributes.get_attribute( name )
end
# Evaluates to +true+ if this element has any attributes set, false
# otherwise.
def has_attributes?
return !@attributes.empty?
end
# Adds an attribute to this element, overwriting any existing attribute
# by the same name.
# key::
# can be either an Attribute or a String. If an Attribute,
# the attribute is added to the list of Element attributes. If String,
# the argument is used as the name of the new attribute, and the value
# parameter must be supplied.
# value::
# Required if +key+ is a String, and ignored if the first argument is
# an Attribute. This is a String, and is used as the value
# of the new Attribute. This should be the unnormalized value of the
# attribute (without entities).
# Returns:: the Attribute added
# e = Element.new 'e'
# e.add_attribute( 'a', 'b' ) #-> <e a='b'/>
# e.add_attribute( 'x:a', 'c' ) #-> <e a='b' x:a='c'/>
# e.add_attribute Attribute.new('b', 'd') #-> <e a='b' x:a='c' b='d'/>
def add_attribute( key, value=nil )
if key.kind_of? Attribute
@attributes << key
else
@attributes[key] = value
end
end
# Add multiple attributes to this element.
# hash:: is either a hash, or array of arrays
# el.add_attributes( {"name1"=>"value1", "name2"=>"value2"} )
# el.add_attributes( [ ["name1","value1"], ["name2"=>"value2"] ] )
def add_attributes hash
if hash.kind_of? Hash
hash.each_pair {|key, value| @attributes[key] = value }
elsif hash.kind_of? Array
hash.each { |value| @attributes[ value[0] ] = value[1] }
end
end
# Removes an attribute
# key::
# either an Attribute or a String. In either case, the
# attribute is found by matching the attribute name to the argument,
# and then removed. If no attribute is found, no action is taken.
# Returns::
# the attribute removed, or nil if this Element did not contain
# a matching attribute
# e = Element.new('E')
# e.add_attribute( 'name', 'Sean' ) #-> <E name='Sean'/>
# r = e.add_attribute( 'sur:name', 'Russell' ) #-> <E name='Sean' sur:name='Russell'/>
# e.delete_attribute( 'name' ) #-> <E sur:name='Russell'/>
# e.delete_attribute( r ) #-> <E/>
def delete_attribute(key)
attr = @attributes.get_attribute(key)
attr.remove unless attr.nil?
end
#################################################
# Other Utilities #
#################################################
# Get an array of all CData children.
# IMMUTABLE
def cdatas
find_all { |child| child.kind_of? CData }.freeze
end
# Get an array of all Comment children.
# IMMUTABLE
def comments
find_all { |child| child.kind_of? Comment }.freeze
end
# Get an array of all Instruction children.
# IMMUTABLE
def instructions
find_all { |child| child.kind_of? Instruction }.freeze
end
# Get an array of all Text children.
# IMMUTABLE
def texts
find_all { |child| child.kind_of? Text }.freeze
end
# == DEPRECATED
# See REXML::Formatters
#
# Writes out this element, and recursively, all children.
# output::
# output an object which supports '<< string'; this is where the
# document will be written.
# indent::
# An integer. If -1, no indenting will be used; otherwise, the
# indentation will be this number of spaces, and children will be
# indented an additional amount. Defaults to -1
# transitive::
# If transitive is true and indent is >= 0, then the output will be
# pretty-printed in such a way that the added whitespace does not affect
# the parse tree of the document
# ie_hack::
# This hack inserts a space before the /> on empty tags to address
# a limitation of Internet Explorer. Defaults to false
#
# out = ''
# doc.write( out ) #-> doc is written to the string 'out'
# doc.write( $stdout ) #-> doc written to the console
def write(output=$stdout, indent=-1, transitive=false, ie_hack=false)
Kernel.warn("#{self.class.name}.write is deprecated. See REXML::Formatters", uplevel: 1)
formatter = if indent > -1
if transitive
require_relative "formatters/transitive"
REXML::Formatters::Transitive.new( indent, ie_hack )
else
REXML::Formatters::Pretty.new( indent, ie_hack )
end
else
REXML::Formatters::Default.new( ie_hack )
end
formatter.write( self, output )
end
private
def __to_xpath_helper node
rv = node.expanded_name.clone
if node.parent
results = node.parent.find_all {|n|
n.kind_of?(REXML::Element) and n.expanded_name == node.expanded_name
}
if results.length > 1
idx = results.index( node )
rv << "[#{idx+1}]"
end
end
rv
end
# A private helper method
def each_with_something( test, max=0, name=nil )
num = 0
@elements.each( name ){ |child|
yield child if test.call(child) and num += 1
return if max>0 and num == max
}
end
end
########################################################################
# ELEMENTS #
########################################################################
# A class which provides filtering of children for Elements, and
# XPath search support. You are expected to only encounter this class as
# the <tt>element.elements</tt> object. Therefore, you are
# _not_ expected to instantiate this yourself.
class Elements
include Enumerable
# Constructor
# parent:: the parent Element
def initialize parent
@element = parent
end
# Fetches a child element. Filters only Element children, regardless of
# the XPath match.
# index::
# the search parameter. This is either an Integer, which
# will be used to find the index'th child Element, or an XPath,
# which will be used to search for the Element. <em>Because
# of the nature of XPath searches, any element in the connected XML
# document can be fetched through any other element.</em> <b>The
# Integer index is 1-based, not 0-based.</b> This means that the first
# child element is at index 1, not 0, and the +n+th element is at index
# +n+, not <tt>n-1</tt>. This is because XPath indexes element children
# starting from 1, not 0, and the indexes should be the same.
# name::
# optional, and only used in the first argument is an
# Integer. In that case, the index'th child Element that has the
# supplied name will be returned. Note again that the indexes start at 1.
# Returns:: the first matching Element, or nil if no child matched
# doc = Document.new '<a><b/><c id="1"/><c id="2"/><d/></a>'
# doc.root.elements[1] #-> <b/>
# doc.root.elements['c'] #-> <c id="1"/>
# doc.root.elements[2,'c'] #-> <c id="2"/>
def []( index, name=nil)
if index.kind_of? Integer
raise "index (#{index}) must be >= 1" if index < 1
name = literalize(name) if name
num = 0
@element.find { |child|
child.kind_of? Element and
(name.nil? ? true : child.has_name?( name )) and
(num += 1) == index
}
else
return XPath::first( @element, index )
#{ |element|
# return element if element.kind_of? Element
#}
#return nil
end
end
# Sets an element, replacing any previous matching element. If no
# existing element is found ,the element is added.
# index:: Used to find a matching element to replace. See []().
# element::
# The element to replace the existing element with
# the previous element
# Returns:: nil if no previous element was found.
#
# doc = Document.new '<a/>'
# doc.root.elements[10] = Element.new('b') #-> <a><b/></a>
# doc.root.elements[1] #-> <b/>
# doc.root.elements[1] = Element.new('c') #-> <a><c/></a>
# doc.root.elements['c'] = Element.new('d') #-> <a><d/></a>
def []=( index, element )
previous = self[index]
if previous.nil?
@element.add element
else
previous.replace_with element
end
return previous
end
# Returns +true+ if there are no +Element+ children, +false+ otherwise
def empty?
@element.find{ |child| child.kind_of? Element}.nil?
end
# Returns the index of the supplied child (starting at 1), or -1 if
# the element is not a child
# element:: an +Element+ child
def index element
rv = 0
found = @element.find do |child|
child.kind_of? Element and
(rv += 1) and
child == element
end
return rv if found == element
return -1
end
# Deletes a child Element
# element::
# Either an Element, which is removed directly; an
# xpath, where the first matching child is removed; or an Integer,
# where the n'th Element is removed.
# Returns:: the removed child
# doc = Document.new '<a><b/><c/><c id="1"/></a>'
# b = doc.root.elements[1]
# doc.root.elements.delete b #-> <a><c/><c id="1"/></a>
# doc.elements.delete("a/c[@id='1']") #-> <a><c/></a>
# doc.root.elements.delete 1 #-> <a/>
def delete element
if element.kind_of? Element
@element.delete element
else
el = self[element]
el.remove if el
end
end
# Removes multiple elements. Filters for Element children, regardless of
# XPath matching.
# xpath:: all elements matching this String path are removed.
# Returns:: an Array of Elements that have been removed
# doc = Document.new '<a><c/><c/><c/><c/></a>'
# deleted = doc.elements.delete_all 'a/c' #-> [<c/>, <c/>, <c/>, <c/>]
def delete_all( xpath )
rv = []
XPath::each( @element, xpath) {|element|
rv << element if element.kind_of? Element
}
rv.each do |element|
@element.delete element
element.remove
end
return rv
end
# Adds an element
# element::
# if supplied, is either an Element, String, or
# Source (see Element.initialize). If not supplied or nil, a
# new, default Element will be constructed
# Returns:: the added Element
# a = Element.new('a')
# a.elements.add(Element.new('b')) #-> <a><b/></a>
# a.elements.add('c') #-> <a><b/><c/></a>
def add element=nil
if element.nil?
Element.new("", self, @element.context)
elsif not element.kind_of?(Element)
Element.new(element, self, @element.context)
else
@element << element
element.context = @element.context
element
end
end
alias :<< :add
# Iterates through all of the child Elements, optionally filtering
# them by a given XPath
# xpath::
# optional. If supplied, this is a String XPath, and is used to
# filter the children, so that only matching children are yielded. Note
# that XPaths are automatically filtered for Elements, so that
# non-Element children will not be yielded
# doc = Document.new '<a><b/><c/><d/>sean<b/><c/><d/></a>'
# doc.root.elements.each {|e|p e} #-> Yields b, c, d, b, c, d elements
# doc.root.elements.each('b') {|e|p e} #-> Yields b, b elements
# doc.root.elements.each('child::node()') {|e|p e}
# #-> Yields <b/>, <c/>, <d/>, <b/>, <c/>, <d/>
# XPath.each(doc.root, 'child::node()', &block)
# #-> Yields <b/>, <c/>, <d/>, sean, <b/>, <c/>, <d/>
def each( xpath=nil )
XPath::each( @element, xpath ) {|e| yield e if e.kind_of? Element }
end
def collect( xpath=nil )
collection = []
XPath::each( @element, xpath ) {|e|
collection << yield(e) if e.kind_of?(Element)
}
collection
end
def inject( xpath=nil, initial=nil )
first = true
XPath::each( @element, xpath ) {|e|
if (e.kind_of? Element)
if (first and initial == nil)
initial = e
first = false
else
initial = yield( initial, e ) if e.kind_of? Element
end
end
}
initial
end
# Returns the number of +Element+ children of the parent object.
# doc = Document.new '<a>sean<b/>elliott<b/>russell<b/></a>'
# doc.root.size #-> 6, 3 element and 3 text nodes
# doc.root.elements.size #-> 3
def size
count = 0
@element.each {|child| count+=1 if child.kind_of? Element }
count
end
# Returns an Array of Element children. An XPath may be supplied to
# filter the children. Only Element children are returned, even if the
# supplied XPath matches non-Element children.
# doc = Document.new '<a>sean<b/>elliott<c/></a>'
# doc.root.elements.to_a #-> [ <b/>, <c/> ]
# doc.root.elements.to_a("child::node()") #-> [ <b/>, <c/> ]
# XPath.match(doc.root, "child::node()") #-> [ sean, <b/>, elliott, <c/> ]
def to_a( xpath=nil )
rv = XPath.match( @element, xpath )
return rv.find_all{|e| e.kind_of? Element} if xpath
rv
end
private
# Private helper class. Removes quotes from quoted strings
def literalize name
name = name[1..-2] if name[0] == ?' or name[0] == ?" #'
name
end
end
########################################################################
# ATTRIBUTES #
########################################################################
# A class that defines the set of Attributes of an Element and provides
# operations for accessing elements in that set.
class Attributes < Hash
# Constructor
# element:: the Element of which this is an Attribute
def initialize element
@element = element
end
# Fetches an attribute value. If you want to get the Attribute itself,
# use get_attribute()
# name:: an XPath attribute name. Namespaces are relevant here.
# Returns::
# the String value of the matching attribute, or +nil+ if no
# matching attribute was found. This is the unnormalized value
# (with entities expanded).
#
# doc = Document.new "<a foo:att='1' bar:att='2' att='&lt;'/>"
# doc.root.attributes['att'] #-> '<'
# doc.root.attributes['bar:att'] #-> '2'
def [](name)
attr = get_attribute(name)
return attr.value unless attr.nil?
return nil
end
def to_a
enum_for(:each_attribute).to_a
end
# Returns the number of attributes the owning Element contains.
# doc = Document "<a x='1' y='2' foo:x='3'/>"
# doc.root.attributes.length #-> 3
def length
c = 0
each_attribute { c+=1 }
c
end
alias :size :length
# Iterates over the attributes of an Element. Yields actual Attribute
# nodes, not String values.
#
# doc = Document.new '<a x="1" y="2"/>'
# doc.root.attributes.each_attribute {|attr|
# p attr.expanded_name+" => "+attr.value
# }
def each_attribute # :yields: attribute
return to_enum(__method__) unless block_given?
each_value do |val|
if val.kind_of? Attribute
yield val
else
val.each_value { |atr| yield atr }
end
end
end
# Iterates over each attribute of an Element, yielding the expanded name
# and value as a pair of Strings.
#
# doc = Document.new '<a x="1" y="2"/>'
# doc.root.attributes.each {|name, value| p name+" => "+value }
def each
return to_enum(__method__) unless block_given?
each_attribute do |attr|
yield [attr.expanded_name, attr.value]
end
end
# Fetches an attribute
# name::
# the name by which to search for the attribute. Can be a
# <tt>prefix:name</tt> namespace name.
# Returns:: The first matching attribute, or nil if there was none. This
# value is an Attribute node, not the String value of the attribute.
# doc = Document.new '<a x:foo="1" foo="2" bar="3"/>'
# doc.root.attributes.get_attribute("foo").value #-> "2"
# doc.root.attributes.get_attribute("x:foo").value #-> "1"
def get_attribute( name )
attr = fetch( name, nil )
if attr.nil?
return nil if name.nil?
# Look for prefix
name =~ Namespace::NAMESPLIT
prefix, n = $1, $2
if prefix
attr = fetch( n, nil )
# check prefix
if attr == nil
elsif attr.kind_of? Attribute
return attr if prefix == attr.prefix
else
attr = attr[ prefix ]
return attr
end
end
element_document = @element.document
if element_document and element_document.doctype
expn = @element.expanded_name
expn = element_document.doctype.name if expn.size == 0
attr_val = element_document.doctype.attribute_of(expn, name)
return Attribute.new( name, attr_val ) if attr_val
end
return nil
end
if attr.kind_of? Hash
attr = attr[ @element.prefix ]
end
return attr
end
# Sets an attribute, overwriting any existing attribute value by the
# same name. Namespace is significant.
# name:: the name of the attribute
# value::
# (optional) If supplied, the value of the attribute. If
# nil, any existing matching attribute is deleted.
# Returns::
# Owning element
# doc = Document.new "<a x:foo='1' foo='3'/>"
# doc.root.attributes['y:foo'] = '2'
# doc.root.attributes['foo'] = '4'
# doc.root.attributes['x:foo'] = nil
def []=( name, value )
if value.nil? # Delete the named attribute
attr = get_attribute(name)
delete attr
return
end
unless value.kind_of? Attribute
if @element.document and @element.document.doctype
value = Text::normalize( value, @element.document.doctype )
else
value = Text::normalize( value, nil )
end
value = Attribute.new(name, value)
end
value.element = @element
old_attr = fetch(value.name, nil)
if old_attr.nil?
store(value.name, value)
elsif old_attr.kind_of? Hash
old_attr[value.prefix] = value
elsif old_attr.prefix != value.prefix
# Check for conflicting namespaces
if value.prefix != "xmlns" and old_attr.prefix != "xmlns"
old_namespace = old_attr.namespace
new_namespace = value.namespace
if old_namespace == new_namespace
raise ParseException.new(
"Namespace conflict in adding attribute \"#{value.name}\": "+
"Prefix \"#{old_attr.prefix}\" = \"#{old_namespace}\" and "+
"prefix \"#{value.prefix}\" = \"#{new_namespace}\"")
end
end
store value.name, {old_attr.prefix => old_attr,
value.prefix => value}
else
store value.name, value
end
return @element
end
# Returns an array of Strings containing all of the prefixes declared
# by this set of # attributes. The array does not include the default
# namespace declaration, if one exists.
# doc = Document.new("<a xmlns='foo' xmlns:x='bar' xmlns:y='twee' "+
# "z='glorp' p:k='gru'/>")
# prefixes = doc.root.attributes.prefixes #-> ['x', 'y']
def prefixes
ns = []
each_attribute do |attribute|
ns << attribute.name if attribute.prefix == 'xmlns'
end
if @element.document and @element.document.doctype
expn = @element.expanded_name
expn = @element.document.doctype.name if expn.size == 0
@element.document.doctype.attributes_of(expn).each {
|attribute|
ns << attribute.name if attribute.prefix == 'xmlns'
}
end
ns
end
def namespaces
namespaces = {}
each_attribute do |attribute|
namespaces[attribute.name] = attribute.value if attribute.prefix == 'xmlns' or attribute.name == 'xmlns'
end
if @element.document and @element.document.doctype
expn = @element.expanded_name
expn = @element.document.doctype.name if expn.size == 0
@element.document.doctype.attributes_of(expn).each {
|attribute|
namespaces[attribute.name] = attribute.value if attribute.prefix == 'xmlns' or attribute.name == 'xmlns'
}
end
namespaces
end
# Removes an attribute
# attribute::
# either a String, which is the name of the attribute to remove --
# namespaces are significant here -- or the attribute to remove.
# Returns:: the owning element
# doc = Document.new "<a y:foo='0' x:foo='1' foo='3' z:foo='4'/>"
# doc.root.attributes.delete 'foo' #-> <a y:foo='0' x:foo='1' z:foo='4'/>"
# doc.root.attributes.delete 'x:foo' #-> <a y:foo='0' z:foo='4'/>"
# attr = doc.root.attributes.get_attribute('y:foo')
# doc.root.attributes.delete attr #-> <a z:foo='4'/>"
def delete( attribute )
name = nil
prefix = nil
if attribute.kind_of? Attribute
name = attribute.name
prefix = attribute.prefix
else
attribute =~ Namespace::NAMESPLIT
prefix, name = $1, $2
prefix = '' unless prefix
end
old = fetch(name, nil)
if old.kind_of? Hash # the supplied attribute is one of many
old.delete(prefix)
if old.size == 1
repl = nil
old.each_value{|v| repl = v}
store name, repl
end
elsif old.nil?
return @element
else # the supplied attribute is a top-level one
super(name)
end
@element
end
# Adds an attribute, overriding any existing attribute by the
# same name. Namespaces are significant.
# attribute:: An Attribute
def add( attribute )
self[attribute.name] = attribute
end
alias :<< :add
# Deletes all attributes matching a name. Namespaces are significant.
# name::
# A String; all attributes that match this path will be removed
# Returns:: an Array of the Attributes that were removed
def delete_all( name )
rv = []
each_attribute { |attribute|
rv << attribute if attribute.expanded_name == name
}
rv.each{ |attr| attr.remove }
return rv
end
# The +get_attribute_ns+ method retrieves a method by its namespace
# and name. Thus it is possible to reliably identify an attribute
# even if an XML processor has changed the prefix.
#
# Method contributed by Henrik Martensson
def get_attribute_ns(namespace, name)
result = nil
each_attribute() { |attribute|
if name == attribute.name &&
namespace == attribute.namespace() &&
( !namespace.empty? || !attribute.fully_expanded_name.index(':') )
# foo will match xmlns:foo, but only if foo isn't also an attribute
result = attribute if !result or !namespace.empty? or
!attribute.fully_expanded_name.index(':')
end
}
result
end
end
end