Class: Parselly::Node

Inherits:
Object
  • Object
show all
Includes:
Enumerable
Defined in:
lib/parselly/node.rb

Overview

Represents a node in the Abstract Syntax Tree (AST) for CSS selectors.

Defined Under Namespace

Classes: ChildList

Constant Summary collapse

SIMPLE_SELECTOR_TYPES = 
Set[
  :type_selector,
  :universal_selector,
  :id_selector,
  :class_selector,
  :attribute_selector,
  :pseudo_class,
  :pseudo_function,
  :pseudo_element,
  :pseudo_element_function
].freeze
COMBINATOR_TYPES = 
{
  child_combinator: '>',
  adjacent_combinator: '+',
  sibling_combinator: '~',
  descendant_combinator: ' ',
  column_combinator: '||'
}.freeze
SPECIFICITY_ZERO_PSEUDO_FUNCTIONS = 
Set['where'].freeze
SPECIFICITY_MAX_ARGUMENT_PSEUDO_FUNCTIONS = 
Set['is', 'not', 'has'].freeze
NTH_PSEUDO_FUNCTIONS = 
Set['nth-child', 'nth-last-child', 'nth-of-type', 'nth-last-of-type', 'nth-col', 'nth-last-col'].freeze

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(type, value = nil, position = {}, raw_value: nil, line: nil, column: nil, offset: nil, start_line: nil, start_column: nil, start_offset: nil, end_line: nil, end_column: nil, end_offset: nil, namespace: nil, quote: nil, modifier: nil, prefix: nil) ⇒ Node

Returns a new instance of Node.



100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
 
# File 'lib/parselly/node.rb', line 100

def initialize(type, value = nil, position = {}, raw_value: nil, line: nil, column: nil, offset: nil,
               start_line: nil, start_column: nil, start_offset: nil,
               end_line: nil, end_column: nil, end_offset: nil,
               namespace: nil, quote: nil, modifier: nil, prefix: nil)
  @type = type
  @value = value
  @raw_value = raw_value.nil? ? value : raw_value
  @children = ChildList.new(self)
  @parent = nil
  @namespace = namespace
  @quote = quote
  @modifier = modifier
  @prefix = prefix
  unless position.nil? || position.is_a?(Hash)
    raise ArgumentError, 'position must be a Hash'
  end

  resolved_position = position ? position.dup : {}
  resolved_position[:line] = line unless line.nil?
  resolved_position[:column] = column unless column.nil?
  resolved_position[:offset] = offset unless offset.nil?
  resolved_position[:start_line] = start_line unless start_line.nil?
  resolved_position[:start_column] = start_column unless start_column.nil?
  resolved_position[:start_offset] = start_offset unless start_offset.nil?
  resolved_position[:end_line] = end_line unless end_line.nil?
  resolved_position[:end_column] = end_column unless end_column.nil?
  resolved_position[:end_offset] = end_offset unless end_offset.nil?
  @position = resolved_position
  @descendants_cache = nil
end

Instance Attribute Details

#children ⇒ Object

Returns the value of attribute children.



98
99
100
 
# File 'lib/parselly/node.rb', line 98

def children
  @children
end

#modifier ⇒ Object

Returns the value of attribute modifier.



97
98
99
 
# File 'lib/parselly/node.rb', line 97

def modifier
  @modifier
end

#namespace ⇒ Object

Returns the value of attribute namespace.



97
98
99
 
# File 'lib/parselly/node.rb', line 97

def namespace
  @namespace
end

#parent ⇒ Object

Returns the value of attribute parent.



97
98
99
 
# File 'lib/parselly/node.rb', line 97

def parent
  @parent
end

#position ⇒ Object

Returns the value of attribute position.



97
98
99
 
# File 'lib/parselly/node.rb', line 97

def position
  @position
end

#prefix ⇒ Object

Returns the value of attribute prefix.



97
98
99
 
# File 'lib/parselly/node.rb', line 97

def prefix
  @prefix
end

#quote ⇒ Object

Returns the value of attribute quote.



97
98
99
 
# File 'lib/parselly/node.rb', line 97

def quote
  @quote
end

#raw_value ⇒ Object

Returns the value of attribute raw_value.



97
98
99
 
# File 'lib/parselly/node.rb', line 97

def raw_value
  @raw_value
end

#type ⇒ Object

Returns the value of attribute type.



97
98
99
 
# File 'lib/parselly/node.rb', line 97

def type
  @type
end

#value ⇒ Object

Returns the value of attribute value.



97
98
99
 
# File 'lib/parselly/node.rb', line 97

def value
  @value
end

Instance Method Details

#add_child(node) ⇒ Object 



136
137
138
139
140
141
 
# File 'lib/parselly/node.rb', line 136

def add_child(node)
  return nil if node.nil?

  @children << node
  node
end

#ancestors ⇒ Object 



182
183
184
185
186
187
188
189
190
 
# File 'lib/parselly/node.rb', line 182

def ancestors
  result = []
  node = parent
  while node
    result << node
    node = node.parent
  end
  result
end

#as_json ⇒ Object 



424
425
426
 
# File 'lib/parselly/node.rb', line 424

def as_json(*)
  to_h
end

#attribute? ⇒ Boolean

Returns:

  • (Boolean) 


311
312
313
 
# File 'lib/parselly/node.rb', line 311

def attribute?
  any? { |node| node.type == :attribute_selector }
end

#attribute_selectors ⇒ Object 



319
320
321
 
# File 'lib/parselly/node.rb', line 319

def attribute_selectors
  attribute_selector_nodes.map { |node| extract_attribute_node(node) }
end

#attributes ⇒ Object 



315
316
317
 
# File 'lib/parselly/node.rb', line 315

def attributes
  attribute_selector_nodes.map { |node| extract_attribute_info(node) }
end

#classes ⇒ Object 



307
308
309
 
# File 'lib/parselly/node.rb', line 307

def classes
  each.with_object([]) { |node, result| result << node.value if node.type == :class_selector }
end

#combinators ⇒ Object 



363
364
365
366
367
368
369
 
# File 'lib/parselly/node.rb', line 363

def combinators
  each.with_object([]) do |node, result|
    next unless COMBINATOR_TYPES.key?(node.type)

    result << { type: node.type, value: node.value, position: node.position }
  end
end

#complex_selector? ⇒ Boolean

Returns:

  • (Boolean) 


375
376
377
 
# File 'lib/parselly/node.rb', line 375

def complex_selector?
  type == :selector || any? { |node| COMBINATOR_TYPES.key?(node.type) }
end

#compound_selector? ⇒ Boolean

Returns:

  • (Boolean) 


379
380
381
382
383
384
385
386
387
388
 
# File 'lib/parselly/node.rb', line 379

def compound_selector?
  case type
  when :selector_list
    children.size == 1 && children.first.compound_selector?
  when :simple_selector_sequence
    children.count { |child| SIMPLE_SELECTOR_TYPES.include?(child.type) } > 1
  else
    false
  end
end

#deconstruct_keys(keys) ⇒ Object 



428
429
430
431
432
433
 
# File 'lib/parselly/node.rb', line 428

def deconstruct_keys(keys)
  hash = to_h
  return hash if keys.nil?

  keys.each_with_object({}) { |key, result| result[key] = hash[key] if hash.key?(key) }
end

#descendants ⇒ Object 



192
193
194
195
196
197
198
199
200
201
202
203
204
205
 
# File 'lib/parselly/node.rb', line 192

def descendants
  return @descendants_cache if @descendants_cache

  @descendants_cache = []
  queue = @children.to_a
  index = 0
  while index < queue.length
    node = queue[index]
    @descendants_cache << node
    queue.concat(node.children) unless node.children.empty?
    index += 1
  end
  @descendants_cache
end

#dup_tree ⇒ Object Also known as: deep_dup 



441
442
443
444
445
446
447
448
449
450
451
452
453
454
 
# File 'lib/parselly/node.rb', line 441

def dup_tree
  duplicate = self.class.new(
    type,
    value,
    position.dup,
    raw_value: raw_value,
    namespace: namespace,
    quote: quote,
    modifier: modifier,
    prefix: prefix
  )
  children.each { |child| duplicate.add_child(child.dup_tree) }
  duplicate
end

#each ⇒ Object 



207
208
209
210
211
212
213
214
215
216
217
218
 
# File 'lib/parselly/node.rb', line 207

def each
  return enum_for(:each) unless block_given?

  stack = [self]
  until stack.empty?
    node = stack.pop
    yield node
    stack.concat(node.children.reverse) unless node.children.empty?
  end

  self
end

#find_all(type) ⇒ Object 



220
221
222
 
# File 'lib/parselly/node.rb', line 220

def find_all(type)
  each.select { |node| node.type == type }
end

#freeze_tree ⇒ Object 



435
436
437
438
439
 
# File 'lib/parselly/node.rb', line 435

def freeze_tree
  children.each(&:freeze_tree)
  children.freeze
  freeze
end

#id ⇒ Object 



299
300
301
 
# File 'lib/parselly/node.rb', line 299

def id
  ids.first
end

#id? ⇒ Boolean

Returns:

  • (Boolean) 


295
296
297
 
# File 'lib/parselly/node.rb', line 295

def id?
  any? { |node| node.type == :id_selector }
end

#ids ⇒ Object 



303
304
305
 
# File 'lib/parselly/node.rb', line 303

def ids
  each.with_object([]) { |node, result| result << node.value if node.type == :id_selector }
end

#insert_after(reference_child, new_child) ⇒ Object 



175
176
177
178
179
180
 
# File 'lib/parselly/node.rb', line 175

def insert_after(reference_child, new_child)
  index = @children.index(reference_child)
  return nil unless index

  insert_child(index + 1, new_child)
end

#insert_before(reference_child, new_child) ⇒ Object 



168
169
170
171
172
173
 
# File 'lib/parselly/node.rb', line 168

def insert_before(reference_child, new_child)
  index = @children.index(reference_child)
  return nil unless index

  insert_child(index, new_child)
end

#insert_child(index, node) ⇒ Object 



150
151
152
153
154
155
156
 
# File 'lib/parselly/node.rb', line 150

def insert_child(index, node)
  return nil if node.nil?
  return nil if index.negative? || index > @children.size

  @children.insert(index, node)
  node
end

#inspect ⇒ Object 



240
241
242
 
# File 'lib/parselly/node.rb', line 240

def inspect
  "#<#{self.class.name} type=#{type} value=#{value.inspect} children=#{children.size}>"
end

#pseudo_class_names ⇒ Object 



331
332
333
 
# File 'lib/parselly/node.rb', line 331

def pseudo_class_names
  each.with_object([]) { |node, result| result << node.value if node.type == :pseudo_class }
end

#pseudo_classes ⇒ Object 



323
324
325
326
327
328
329
 
# File 'lib/parselly/node.rb', line 323

def pseudo_classes
  each.with_object([]) do |node, result|
    if [:pseudo_class, :pseudo_element, :pseudo_function, :pseudo_element_function].include?(node.type)
      result << node.value
    end
  end
end

#pseudo_element_names ⇒ Object 



335
336
337
338
339
 
# File 'lib/parselly/node.rb', line 335

def pseudo_element_names
  each.with_object([]) do |node, result|
    result << node.value if [:pseudo_element, :pseudo_element_function].include?(node.type)
  end
end

#pseudo_function_names ⇒ Object 



341
342
343
 
# File 'lib/parselly/node.rb', line 341

def pseudo_function_names
  each.with_object([]) { |node, result| result << node.value if node.type == :pseudo_function }
end

#remove_child(node_or_index) ⇒ Object 



158
159
160
161
162
163
164
165
166
 
# File 'lib/parselly/node.rb', line 158

def remove_child(node_or_index)
  if node_or_index.is_a?(Integer)
    return nil if node_or_index.negative? || node_or_index >= @children.size

    return @children.delete_at(node_or_index)
  end

  @children.delete(node_or_index)
end

#replace_child(index, new_node) ⇒ Object 



143
144
145
146
147
148
 
# File 'lib/parselly/node.rb', line 143

def replace_child(index, new_node)
  return nil if new_node.nil?
  return nil if index.negative? || index >= @children.size

  @children[index] = new_node
end

#selector_list? ⇒ Boolean

Returns:

  • (Boolean) 


371
372
373
 
# File 'lib/parselly/node.rb', line 371

def selector_list?
  type == :selector_list
end

#siblings ⇒ Object 



224
225
226
227
228
 
# File 'lib/parselly/node.rb', line 224

def siblings
  return [] unless parent

  parent.children.reject { |child| child == self }
end

#specificity ⇒ Object 



390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
 
# File 'lib/parselly/node.rb', line 390

def specificity
  case type
  when :selector_list
    children.map(&:specificity).max || [0, 0, 0]
  when :selector, :simple_selector_sequence
    children.reduce([0, 0, 0]) { |sum, child| add_specificity(sum, child.specificity) }
  when :id_selector
    [1, 0, 0]
  when :class_selector, :attribute_selector, :pseudo_class
    [0, 1, 0]
  when :type_selector, :pseudo_element, :pseudo_element_function
    [0, 0, 1]
  when :pseudo_function
    pseudo_function_specificity
  else
    [0, 0, 0]
  end
end

#to_h ⇒ Object 



409
410
411
412
413
414
415
416
417
418
419
420
421
422
 
# File 'lib/parselly/node.rb', line 409

def to_h
  hash = {
    type: type,
    value: value,
    raw_value: raw_value,
    namespace: namespace,
    quote: quote,
    modifier: modifier,
    prefix: prefix,
    position: position,
    children: children.map(&:to_h)
  }
  hash.delete_if { |key, val| key != :children && (val.nil? || val == {}) }
end

#to_selector(mode: :normalized) ⇒ Object 



244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
 
# File 'lib/parselly/node.rb', line 244

def to_selector(mode: :normalized)
  validate_selector_mode!(mode)

  case type
  when :selector_list
    children.map { |child| child.to_selector(mode: mode) }.join(', ')
  when :selector
    build_selector(mode)
  when :simple_selector_sequence
    children.map { |child| child.to_selector(mode: mode) }.join
  when :type_selector, :universal_selector
    selector_name(mode)
  when :id_selector
    "##{selector_identifier(mode)}"
  when :class_selector
    ".#{selector_identifier(mode)}"
  when :attribute_selector
    build_attribute_selector(mode)
  when :pseudo_class
    "#{selector_prefix(mode, ':')}#{selector_identifier(mode)}"
  when :pseudo_element
    "#{selector_prefix(mode, '::')}#{selector_identifier(mode)}"
  when :pseudo_function
    "#{selector_prefix(mode, ':')}#{selector_identifier(mode)}(#{children.map { |child| child.to_selector(mode: mode) }.join})"
  when :pseudo_element_function
    "#{selector_prefix(mode, '::')}#{selector_identifier(mode)}(#{children.map { |child| child.to_selector(mode: mode) }.join})"
  when :child_combinator
    ' > '
  when :adjacent_combinator
    ' + '
  when :sibling_combinator
    ' ~ '
  when :descendant_combinator
    ' '
  when :column_combinator
    ' || '
  when :nth_selector_argument
    "#{children[0].to_selector(mode: mode)} of #{children[1].to_selector(mode: mode)}"
  when :an_plus_b
    value.to_s
  when :argument
    argument_selector(mode)
  when :attribute, :value,
       :equal_operator, :includes_operator, :dashmatch_operator,
       :prefixmatch_operator, :suffixmatch_operator, :substringmatch_operator
    value.to_s
  else
    children.map { |child| child.to_selector(mode: mode) }.join
  end
end

#to_tree(indent = 0) ⇒ Object 



230
231
232
233
234
235
236
237
238
 
# File 'lib/parselly/node.rb', line 230

def to_tree(indent = 0)
  lines = []
  prefix = '  ' * indent
  pos_info = position.empty? ? '' : " [#{position[:line]}:#{position[:column]}]"

  lines << "#{prefix}#{type}#{"(#{value.inspect})" if value}#{pos_info}"
  children.each { |child| lines << child.to_tree(indent + 1) }
  lines.join("\n")
end

#type_names ⇒ Object 



349
350
351
 
# File 'lib/parselly/node.rb', line 349

def type_names
  each.with_object([]) { |node, result| result << node.value if node.type == :type_selector }
end

#type_selector? ⇒ Boolean

Returns:

  • (Boolean) 


345
346
347
 
# File 'lib/parselly/node.rb', line 345

def type_selector?
  any? { |node| node.type == :type_selector }
end

#type_selectors ⇒ Object 



353
354
355
356
357
358
359
360
361
 
# File 'lib/parselly/node.rb', line 353

def type_selectors
  each.with_object([]) do |node, result|
    next unless node.type == :type_selector

    detail = { name: node.value, raw_name: node.raw_value, position: node.position }
    detail[:namespace] = node.namespace unless node.namespace.nil?
    result << detail
  end
end