Class: TreeHaver::Backends::Psych::Node

Inherits:
Object
  • Object
show all
Includes:
Comparable, Enumerable
Defined in:
lib/tree_haver/backends/psych.rb

Overview

Psych node wrapper

Wraps Psych::Nodes::* classes to provide TreeHaver::Node-compatible interface.

Psych node types:

  • Stream: Root container

  • Document: YAML document (multiple per stream possible)

  • Mapping: Hash/object

  • Sequence: Array/list

  • Scalar: Primitive value (string, number, boolean, null)

  • Alias: YAML anchor reference

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(node, source, lines = nil) ⇒ Node

Create a new node wrapper

Parameters:

  • node (::Psych::Nodes::Node) —

    Psych node

  • source (String) —

    Original source

  • lines (Array<String>) (defaults to: nil) —

    Source lines for text extraction



247
248
249
250
251
 
# File 'lib/tree_haver/backends/psych.rb', line 247

def initialize(node, source, lines = nil)
  @inner_node = node
  @source = source
  @lines = lines || source.lines
end

Instance Attribute Details

#inner_node ⇒ ::Psych::Nodes::Node (readonly)

Returns The underlying Psych node.

Returns:

  • (::Psych::Nodes::Node) —

    The underlying Psych node



237
238
239
 
# File 'lib/tree_haver/backends/psych.rb', line 237

def inner_node
  @inner_node
end

#source ⇒ String (readonly)

Returns The original source.

Returns:

  • (String) —

    The original source



240
241
242
 
# File 'lib/tree_haver/backends/psych.rb', line 240

def source
  @source
end

Instance Method Details

#<=>(other) ⇒ Integer?

Comparison for sorting

Parameters:

  • other (Node) —

    other node

Returns:

  • (Integer, nil) —

    comparison result



438
439
440
441
442
443
 
# File 'lib/tree_haver/backends/psych.rb', line 438

def <=>(other)
  return unless other.respond_to?(:start_byte)
  cmp = start_byte <=> other.start_byte
  return cmp unless cmp&.zero?
  end_byte <=> other.end_byte
end

#alias? ⇒ Boolean

Psych-specific: Check if this is an alias

Returns:

  • (Boolean) 


519
520
521
 
# File 'lib/tree_haver/backends/psych.rb', line 519

def alias?
  @inner_node.is_a?(::Psych::Nodes::Alias)
end

#anchor ⇒ String?

Psych-specific: Get the anchor name for Alias/anchored nodes

Returns:

  • (String, nil) —

    Anchor name



477
478
479
 
# File 'lib/tree_haver/backends/psych.rb', line 477

def anchor
  @inner_node.anchor if @inner_node.respond_to?(:anchor)
end

#child(index) ⇒ Node?

Get child by index

Parameters:

  • index (Integer) —

    Child index

Returns:

  • (Node, nil) —

    Child node



318
319
320
 
# File 'lib/tree_haver/backends/psych.rb', line 318

def child(index)
  children[index]
end

#child_count ⇒ Integer

Get the number of children

Returns:

  • (Integer) —

    Child count



310
311
312
 
# File 'lib/tree_haver/backends/psych.rb', line 310

def child_count
  children.size
end

#children ⇒ Array<Node>

Get child nodes

Returns:

  • (Array<Node>) —

    Child nodes



292
293
294
295
296
 
# File 'lib/tree_haver/backends/psych.rb', line 292

def children
  return [] unless @inner_node.respond_to?(:children) && @inner_node.children

  @inner_node.children.map { |child| Node.new(child, @source, @lines) }
end

#each {|Node| ... } ⇒ Enumerator?

Iterate over child nodes

Yields:

  • (Node) —

    Each child node

Returns:

  • (Enumerator, nil) 


302
303
304
305
 
# File 'lib/tree_haver/backends/psych.rb', line 302

def each(&block)
  return to_enum(__method__) unless block
  children.each(&block)
end

#end_byte ⇒ Integer

Get end byte offset

Returns:

  • (Integer) —

    End byte offset



338
339
340
341
342
343
344
 
# File 'lib/tree_haver/backends/psych.rb', line 338

def end_byte
  return start_byte + text.bytesize unless @inner_node.respond_to?(:end_line)

  line = @inner_node.end_line || 0
  col = @inner_node.end_column || 0
  calculate_byte_offset(line, col)
end

#end_line ⇒ Integer

Get the 1-based line number where this node ends

Returns:

  • (Integer) —

    1-based line number



377
378
379
380
 
# File 'lib/tree_haver/backends/psych.rb', line 377

def end_line
  row = end_point.row
  row + 1
end

#end_point ⇒ Point

Get end point (row, column)

Returns:

  • (Point) —

    End position (0-based)



358
359
360
361
362
 
# File 'lib/tree_haver/backends/psych.rb', line 358

def end_point
  row = (@inner_node.respond_to?(:end_line) ? @inner_node.end_line : 0) || 0
  col = (@inner_node.respond_to?(:end_column) ? @inner_node.end_column : 0) || 0
  Point.new(row, col)
end

#first_child ⇒ Node?

Get the first child node

Returns:

  • (Node, nil) —

    First child or nil



400
401
402
 
# File 'lib/tree_haver/backends/psych.rb', line 400

def first_child
  children.first
end

#has_error? ⇒ Boolean

Check if the node or any descendant has an error

Psych raises on errors rather than embedding them.

Returns:

  • (Boolean) —

    false



421
422
423
 
# File 'lib/tree_haver/backends/psych.rb', line 421

def has_error?
  false
end

#inspect ⇒ String

Returns human-readable representation.

Returns:

  • (String) —

    human-readable representation



446
447
448
 
# File 'lib/tree_haver/backends/psych.rb', line 446

def inspect
  "#<TreeHaver::Backends::Psych::Node type=#{type} children=#{child_count}>"
end

#mapping? ⇒ Boolean

Psych-specific: Check if this is a mapping (hash)

Returns:

  • (Boolean) 


498
499
500
 
# File 'lib/tree_haver/backends/psych.rb', line 498

def mapping?
  @inner_node.is_a?(::Psych::Nodes::Mapping)
end

#mapping_entries ⇒ Array<Array(Node, Node)>

Psych-specific: Get mapping entries as key-value pairs

For Mapping nodes, children alternate key, value, key, value…

Returns:

  • (Array<Array(Node, Node)>) —

    Key-value pairs



528
529
530
531
532
533
534
535
536
 
# File 'lib/tree_haver/backends/psych.rb', line 528

def mapping_entries
  return [] unless mapping?

  pairs = []
  children.each_slice(2) do |key, val|
    pairs << [key, val] if key && val
  end
  pairs
end

#missing? ⇒ Boolean

Check if this is a missing node

Psych doesn’t have missing nodes.

Returns:

  • (Boolean) —

    false



430
431
432
 
# File 'lib/tree_haver/backends/psych.rb', line 430

def missing?
  false
end

#named? ⇒ Boolean Also known as: structural?

Check if this is a named (structural) node

All Psych nodes are structural.

Returns:

  • (Boolean) —

    true



409
410
411
 
# File 'lib/tree_haver/backends/psych.rb', line 409

def named?
  true
end

#next_sibling ⇒ void

This method returns an undefined value.

Get the next sibling

Raises:

  • (NotImplementedError) —

    Psych nodes don’t have sibling references



454
455
456
 
# File 'lib/tree_haver/backends/psych.rb', line 454

def next_sibling
  raise NotImplementedError, "Psych backend does not support sibling navigation"
end

#parent ⇒ void

This method returns an undefined value.

Get the parent node

Raises:

  • (NotImplementedError) —

    Psych nodes don’t have parent references



470
471
472
 
# File 'lib/tree_haver/backends/psych.rb', line 470

def parent
  raise NotImplementedError, "Psych backend does not support parent navigation"
end

#prev_sibling ⇒ void

This method returns an undefined value.

Get the previous sibling

Raises:

  • (NotImplementedError) —

    Psych nodes don’t have sibling references



462
463
464
 
# File 'lib/tree_haver/backends/psych.rb', line 462

def prev_sibling
  raise NotImplementedError, "Psych backend does not support sibling navigation"
end

#scalar? ⇒ Boolean

Psych-specific: Check if this is a scalar (primitive)

Returns:

  • (Boolean) 


512
513
514
 
# File 'lib/tree_haver/backends/psych.rb', line 512

def scalar?
  @inner_node.is_a?(::Psych::Nodes::Scalar)
end

#sequence? ⇒ Boolean

Psych-specific: Check if this is a sequence (array)

Returns:

  • (Boolean) 


505
506
507
 
# File 'lib/tree_haver/backends/psych.rb', line 505

def sequence?
  @inner_node.is_a?(::Psych::Nodes::Sequence)
end

#source_position ⇒ Hash{Symbol => Integer}

Get position information as a hash

Returns a hash with 1-based line numbers and 0-based columns. Compatible with *-merge gems’ FileAnalysisBase.

Returns:

  • (Hash{Symbol => Integer}) —

    Position hash



388
389
390
391
392
393
394
395
 
# File 'lib/tree_haver/backends/psych.rb', line 388

def source_position
  {
    start_line: start_line,
    end_line: end_line,
    start_column: start_point.column,
    end_column: end_point.column,
  }
end

#start_byte ⇒ Integer

Get start byte offset

Psych doesn’t provide byte offsets directly, so we calculate from line/column.

Returns:

  • (Integer) —

    Start byte offset



327
328
329
330
331
332
333
 
# File 'lib/tree_haver/backends/psych.rb', line 327

def start_byte
  return 0 unless @inner_node.respond_to?(:start_line)

  line = @inner_node.start_line || 0
  col = @inner_node.start_column || 0
  calculate_byte_offset(line, col)
end

#start_line ⇒ Integer

Get the 1-based line number where this node starts

Psych provides 0-based line numbers, so we add 1.

Returns:

  • (Integer) —

    1-based line number



369
370
371
372
 
# File 'lib/tree_haver/backends/psych.rb', line 369

def start_line
  row = start_point.row
  row + 1
end

#start_point ⇒ Point

Get start point (row, column)

Returns:

  • (Point) —

    Start position (0-based)



349
350
351
352
353
 
# File 'lib/tree_haver/backends/psych.rb', line 349

def start_point
  row = (@inner_node.respond_to?(:start_line) ? @inner_node.start_line : 0) || 0
  col = (@inner_node.respond_to?(:start_column) ? @inner_node.start_column : 0) || 0
  Point.new(row, col)
end

#tag ⇒ String?

Psych-specific: Get the tag for tagged nodes

Returns:

  • (String, nil) —

    Tag



484
485
486
 
# File 'lib/tree_haver/backends/psych.rb', line 484

def tag
  @inner_node.tag if @inner_node.respond_to?(:tag)
end

#text ⇒ String

Get the text content of this node

For Scalar nodes, returns the value. For containers, returns the source text spanning the node’s location.

Returns:

  • (String) —

    Node text



277
278
279
280
281
282
283
284
285
286
287
 
# File 'lib/tree_haver/backends/psych.rb', line 277

def text
  case @inner_node
  when ::Psych::Nodes::Scalar
    @inner_node.value.to_s
  when ::Psych::Nodes::Alias
    "*#{@inner_node.anchor}"
  else
    # For container nodes, extract from source using location
    extract_text_from_location
  end
end

#type ⇒ String Also known as: kind

Get the node type as a string

Maps Psych class names to lowercase type strings:

  • Psych::Nodes::Stream → “stream”

  • Psych::Nodes::Document → “document”

  • Psych::Nodes::Mapping → “mapping”

  • Psych::Nodes::Sequence → “sequence”

  • Psych::Nodes::Scalar → “scalar”

  • Psych::Nodes::Alias → “alias”

Returns:

  • (String) —

    Node type



264
265
266
 
# File 'lib/tree_haver/backends/psych.rb', line 264

def type
  @inner_node.class.name.split("::").last.downcase
end

#value ⇒ String?

Psych-specific: Get the scalar value

Returns:

  • (String, nil) —

    Value for scalar nodes



491
492
493
 
# File 'lib/tree_haver/backends/psych.rb', line 491

def value
  @inner_node.value if @inner_node.respond_to?(:value)
end