Module: Coradoc::AsciiDoc::Transformer::SourceLineExtractor

Defined in:
lib/coradoc/asciidoc/transformer/source_line_extractor.rb

Overview

Walks a Parslet AST subtree (Hash/Array/Slice/String/Model) and returns the 1-indexed source line of the first Parslet::Slice or Model::Base#source_line it finds.

Parslet preserves byte offsets on every matched slice (+slice.line_and_column+ returns [line, column]); the transformer receives these slices in the AST but most rules discard the position when building Model objects. This helper recovers the start line of any subtree so transformer rules can populate Model::Base#source_line without changing the parser.

Handles two distinct shapes:

* Pre-transform AST (Hash/Array of Parslet::Slice) — used by
rules that bind raw slices via +simple(:x)+.
* Post-transform Model tree (Model::Base instances whose
+source_line+ was populated by an earlier rule) — used by
rules that bind via +subtree(:x)+ and receive already-
transformed content.

Returns nil when no position is found (programmatic input, already-stripped ASTs, etc.) — callers should treat nil as "source position unavailable".

Class Method Summary collapse

Class Method Details

.extract(node) ⇒ Object 



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# File 'lib/coradoc/asciidoc/transformer/source_line_extractor.rb', line 34

def extract(node)
  case node
  when Parslet::Slice then line_of(node)
  when Coradoc::AsciiDoc::Model::Base then node.source_line
  when Hash then extract_from_hash(node)
  when Array then extract_from_array(node)
  end
end

.extract_from_array(array) ⇒ Object 



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# File 'lib/coradoc/asciidoc/transformer/source_line_extractor.rb', line 56

def extract_from_array(array)
  array.each do |value|
    line = extract(value)
    return line if line
  end
  nil
end

.extract_from_hash(hash) ⇒ Object 



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# File 'lib/coradoc/asciidoc/transformer/source_line_extractor.rb', line 48

def extract_from_hash(hash)
  hash.each_value do |value|
    line = extract(value)
    return line if line
  end
  nil
end

.line_of(slice) ⇒ Object 



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# File 'lib/coradoc/asciidoc/transformer/source_line_extractor.rb', line 43

def line_of(slice)
  line, _column = slice.line_and_column
  line
end