Class: Nokogiri::CSS::XPathVisitor

Inherits:
Object
  • Object
show all
Defined in:
lib/nokogiri/css/xpath_visitor.rb

Overview

:nodoc:

Instance Method Summary collapse

Instance Method Details

#accept(node) ⇒ Object 



141
142
143
 
# File 'lib/nokogiri/css/xpath_visitor.rb', line 141

def accept node
  node.accept(self)
end

#visit_attribute_condition(node) ⇒ Object 



56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
 
# File 'lib/nokogiri/css/xpath_visitor.rb', line 56

def visit_attribute_condition node
   attribute = if (node.value.first.type == :FUNCTION) or (node.value.first.value.first =~ /::/)
                 ''
               else
                 '@'
               end
  attribute += node.value.first.accept(self)

  # Support non-standard css
  attribute.gsub!(/^@@/, '@')

  return attribute unless node.value.length == 3

  value = node.value.last
  value = "'#{value}'" if value !~ /^['"]/

  case node.value[1]
  when :equal
    attribute + " = " + "#{value}"
  when :not_equal
    attribute + " != " + "#{value}"
  when :substring_match
    "contains(#{attribute}, #{value})"
  when :prefix_match
    "starts-with(#{attribute}, #{value})"
  when :dash_match
    "#{attribute} = #{value} or starts-with(#{attribute}, concat(#{value}, '-'))"
  when :includes
    "contains(concat(\" \", #{attribute}, \" \"),concat(\" \", #{value}, \" \"))"
  when :suffix_match
    "substring(#{attribute}, string-length(#{attribute}) - " +
      "string-length(#{value}) + 1, string-length(#{value})) = #{value}"
  else
    attribute + " #{node.value[1]} " + "#{value}"
  end
end

#visit_class_condition(node) ⇒ Object 



115
116
117
 
# File 'lib/nokogiri/css/xpath_visitor.rb', line 115

def visit_class_condition node
  "contains(concat(' ', @class, ' '), ' #{node.value.first} ')"
end

#visit_conditional_selector(node) ⇒ Object 



132
133
134
135
 
# File 'lib/nokogiri/css/xpath_visitor.rb', line 132

def visit_conditional_selector node
  node.value.first.accept(self) + '[' +
  node.value.last.accept(self) + ']'
end

#visit_element_name(node) ⇒ Object 



137
138
139
 
# File 'lib/nokogiri/css/xpath_visitor.rb', line 137

def visit_element_name node
  node.value.first
end

#visit_function(node) ⇒ Object 



4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
 
# File 'lib/nokogiri/css/xpath_visitor.rb', line 4

def visit_function node
  #  note that nth-child and nth-last-child are preprocessed in css/node.rb.
  msg = :"visit_function_#{node.value.first.gsub(/[(]/, '')}"
  return self.send(msg, node) if self.respond_to?(msg)

  case node.value.first
  when /^text\(/
    'child::text()'
  when /^self\(/
    "self::#{node.value[1]}"
  when /^(eq|nth|nth-of-type|nth-child)\(/
    if node.value[1].is_a?(Nokogiri::CSS::Node) and node.value[1].type == :AN_PLUS_B
      an_plus_b(node.value[1])
    else
      "position() = " + node.value[1]
    end
  when /^(first|first-of-type)\(/
    "position() = 1"
  when /^(last|last-of-type)\(/
    "position() = last()"
  when /^(nth-last-child|nth-last-of-type)\(/
    "position() = last() - #{node.value[1]}"
  when /^contains\(/
    "contains(., #{node.value[1]})"
  when /^gt\(/
    "position() > #{node.value[1]}"
  when /^only-child\(/
    "last() = 1"
  when /^comment\(/
    "comment()"
  else
    args = ['.'] + node.value[1..-1]
    "#{node.value.first}#{args.join(', ')})"
  end
end

#visit_id(node) ⇒ Object 



51
52
53
54
 
# File 'lib/nokogiri/css/xpath_visitor.rb', line 51

def visit_id node
  node.value.first =~ /^#(.*)$/
  "@id = '#{$1}'"
end

#visit_not(node) ⇒ Object 



40
41
42
 
# File 'lib/nokogiri/css/xpath_visitor.rb', line 40

def visit_not node
  'not(' + node.value.first.accept(self) + ')'
end

#visit_preceding_selector(node) ⇒ Object 



44
45
46
47
48
49
 
# File 'lib/nokogiri/css/xpath_visitor.rb', line 44

def visit_preceding_selector node
  node.value.last.accept(self) +
    '[preceding-sibling::' +
    node.value.first.accept(self) +
    ']'
end

#visit_pseudo_class(node) ⇒ Object 



93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
 
# File 'lib/nokogiri/css/xpath_visitor.rb', line 93

def visit_pseudo_class node
  if node.value.first.is_a?(Nokogiri::CSS::Node) and node.value.first.type == :FUNCTION
    node.value.first.accept(self)
  else
    msg = :"visit_pseudo_class_#{node.value.first.gsub(/[(]/, '')}"
    return self.send(msg, node) if self.respond_to?(msg)

    case node.value.first
    when "first" then "position() = 1"
    when "last" then "position() = last()"
    when "first-of-type" then "position() = 1"
    when "last-of-type" then "position() = last()"
    when "only-of-type" then "last() = 1"
    when "empty" then "not(node())"
    when "parent" then "node()"
    when "root" then "not(parent::*)"
    else
      node.value.first + "(.)"
    end
  end
end