Module: RedQuilt::ReferenceDefinition

Defined in:
lib/red_quilt/reference_definition.rb

Overview

CommonMark link reference definitions (‘[label]: dest “title”`).

Module-level functions are stateless helpers reused by BlockParser (fenced-code info string also calls ‘unescape_text`) and Inline::Builder (reference lookup uses `normalize_label`). `ReferenceDefinition::Parser` carries the per-call state (`@lines`, `@index`) and walks the lines for one definition attempt.

Defined Under Namespace

Classes: Parser

Constant Summary collapse

REF_DEF_RE =

A reference label may contain ‘[` / `]` (backslash-escaped), but never an unescaped `[` or `]`. Newlines inside the label are allowed and collapsed by normalize_label.

/\A {0,3}\[((?:[^\\\[\]]|\\.)+)\]:(.*)\z/m
TITLE_CLOSERS = 
{ '"' => '"', "'" => "'", "(" => ")" }.freeze
LABEL_MAX_LENGTH =

CommonMark spec: “A link label can have at most 999 characters inside the square brackets.” Applies to both reference definitions and reference link uses.

999
/[ \t]/

Class Method Summary collapse

Class Method Details

.consume(lines, index) ⇒ Object

Attempts to consume a reference definition starting at ‘lines`. Returns `{ reference: { label:, destination:, title: }, consumed: N, source_span: SourceSpan }` or nil. The reference hash is what BlockParser should store in its @references table; the source_span covers the byte range of the consumed lines (useful for duplicate-definition diagnostics).



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# File 'lib/red_quilt/reference_definition.rb', line 55

def consume(lines, index)
  Parser.new(lines, index).consume
end

.label_too_long?(text) ⇒ Boolean

True when ‘text` exceeds the spec’s link-label length limit.

Returns:

  • (Boolean) 


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# File 'lib/red_quilt/reference_definition.rb', line 33

def label_too_long?(text)
  text.to_s.length > LABEL_MAX_LENGTH
end

.link_blank?(text) ⇒ Boolean

True when the string is empty or contains only spaces and tabs.

Returns:

  • (Boolean) 


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# File 'lib/red_quilt/reference_definition.rb', line 45

def link_blank?(text)
  text.match?(/\A[ \t]*\z/)
end

.link_lstrip(text) ⇒ Object

Narrow lstrip: only space and tab. Used for the spec-defined whitespace around link destinations and titles in reference definitions.



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# File 'lib/red_quilt/reference_definition.rb', line 40

def link_lstrip(text)
  text.sub(/\A[ \t]+/, "")
end

.normalize_label(label) ⇒ Object

Spec-required normalization: full Unicode case fold + whitespace collapse. Inline::Builder uses the same rule when looking up the destination of a reference link.



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# File 'lib/red_quilt/reference_definition.rb', line 70

def normalize_label(label)
  # CommonMark spec: full Unicode case fold (`downcase(:fold)`), not
  # the default per-codepoint lowercase. This makes labels like `ẞ`
  # (U+1E9E) match a definition of `SS` because the case-fold of `ẞ`
  # is `ss`.
  label.to_s.strip.downcase(:fold).gsub(/[ \t\r\n]+/, " ")
end

.unescape_text(text) ⇒ Object

Unescape Markdown text: backslash-escapes for ASCII punctuation and HTML entity references. Also used by BlockParser#fenced_code_start for the info string, which shares the same unescape semantics.



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# File 'lib/red_quilt/reference_definition.rb', line 62

def unescape_text(text)
  out = text.gsub(/\\([!-\/:-@\[-`{-~])/, "\\1")
  out.gsub(Inline::ENTITY_RE) { |m| Inline.decode_entity(m) }
end