Decouple Formatter from RDoc::Options

`Formatter#initialize` took an `RDoc::Options` object, but only 2
subclasses (`ToHtml`, `ToHtmlCrossref`) read from it — using just 6
specific boolean/array values. All other formatters passed `nil`.

Replace the `options` parameter with explicit keyword arguments:
- `ToHtml`: `pipe:`, `output_decoration:`
- `ToHtmlCrossref`: `pipe:`, `output_decoration:`, `hyperlink_all:`,
  `show_hash:`, `autolink_excluded_words:`, `warn_missing_rdoc_ref:`

Call sites (`Generator::Markup#formatter`, `RDoc::RDoc#handle_pipe`)
now unpack the needed values from `RDoc::Options` at the boundary.

`ToHtmlSnippet` and `Text#snippet` no longer receive or forward options.

Delete `LinkLabelToHtml` (zero callers in the codebase).

Update `CodeObject#options` comment to reflect remaining callers.

Author: st0012

lib/rdoc/code_object.rb

@@ -277,7 +277,8 @@ def ignored?
   # The options instance from the store this CodeObject is attached to, or a
   # default options instance if the CodeObject is not attached.
   #
-  # This is used by Text#snippet
+  # Used by: store= (visibility check), ClassModule#path, TopLevel#path,
+  #          ClassModule#embed_mixins
 
   def options
     @store&.options || RDoc::Options.new

lib/rdoc/generator/markup.rb

@@ -37,7 +37,15 @@ def formatter
     options = @store.options
     this = RDoc::Context === self ? self : @parent
 
-    @formatter = RDoc::Markup::ToHtmlCrossref.new options, this.path, this
+    @formatter = RDoc::Markup::ToHtmlCrossref.new(
+      this.path, this,
+      pipe: options.pipe,
+      output_decoration: options.output_decoration,
+      hyperlink_all: options.hyperlink_all,
+      show_hash: options.show_hash,
+      autolink_excluded_words: options.autolink_excluded_words || [],
+      warn_missing_rdoc_ref: options.warn_missing_rdoc_ref
+    )
     @formatter.code_object = self
     @formatter
   end

lib/rdoc/markup/formatter.rb

@@ -48,9 +48,7 @@ def self.gen_relative_url(path, target)
   ##
   # Creates a new Formatter
 
-  def initialize(options)
-    @options = options
-
+  def initialize
     @markup = RDoc::Markup.new
 
     @from_path = '.'

lib/rdoc/markup/heading.rb

@@ -52,7 +52,7 @@ def self.to_label
       #: () -> RDoc::Markup::ToHtml
       def self.to_html
         @to_html ||= begin
-          to_html = Markup::ToHtml.new nil
+          to_html = Markup::ToHtml.new
 
           def to_html.handle_regexp_CROSSREF(text)
             text.sub(/^\\/, '')

lib/rdoc/markup/to_html.rb

@@ -43,9 +43,11 @@ class RDoc::Markup::ToHtml < RDoc::Markup::Formatter
   ##
   # Creates a new formatter that will output HTML
 
-  def initialize(options)
-    super
+  def initialize(pipe: false, output_decoration: true)
+    super()
 
+    @pipe = pipe
+    @output_decoration = output_decoration
     @code_object = nil
     @from_path = ''
     @in_list_entry = nil
@@ -347,7 +349,7 @@ def accept_verbatim(verbatim)
                 CGI.escapeHTML text
               end
 
-    if @options.pipe then
+    if @pipe
       @res << "\n<pre><code>#{CGI.escapeHTML text}\n</code></pre>\n"
     else
       @res << "\n<pre#{klass}>#{content}</pre>\n"
@@ -418,17 +420,17 @@ def accept_heading(heading)
 
     # Add legacy anchor before the heading for backward compatibility.
     # This allows old links with label- prefix to still work.
-    if @options.output_decoration && !@options.pipe
+    if @output_decoration && !@pipe
       @res << "\n<span id=\"#{legacy_label}\" class=\"legacy-anchor\"></span>"
     end
 
-    @res << if @options.output_decoration
+    @res << if @output_decoration
               "\n<h#{level} id=\"#{label}\">"
             else
               "\n<h#{level}>"
             end
 
-    if @options.pipe
+    if @pipe
       @res << to_html(heading.text)
     else
       @res << "<a href=\"##{label}\">#{to_html(heading.text)}</a>"
@@ -586,19 +588,3 @@ def to_html(item)
     to_html_characters(handle_inline(item))
   end
 end
-
-##
-# Formatter dedicated to rendering tidy link labels without mutating the
-# calling formatter's state.
-
-class RDoc::Markup::LinkLabelToHtml < RDoc::Markup::ToHtml
-  def self.render(label, options, from_path)
-    new(options, from_path).to_html(label)
-  end
-
-  def initialize(options, from_path = nil)
-    super(options)
-
-    self.from_path = from_path if from_path
-  end
-end

lib/rdoc/markup/to_html_crossref.rb

@@ -29,15 +29,19 @@ class RDoc::Markup::ToHtmlCrossref < RDoc::Markup::ToHtml
   # references are removed unless +show_hash+ is true.  Only method names
   # preceded by '#' or '::' are linked, unless +hyperlink_all+ is true.
 
-  def initialize(options, from_path, context)
+  def initialize(from_path, context, pipe: false, output_decoration: true,
+                 hyperlink_all: false, show_hash: false,
+                 autolink_excluded_words: [], warn_missing_rdoc_ref: true)
     raise ArgumentError, 'from_path cannot be nil' if from_path.nil?
 
-    super options
+    super(pipe: pipe, output_decoration: output_decoration)
 
     @context       = context
     @from_path     = from_path
-    @hyperlink_all = @options.hyperlink_all
-    @show_hash     = @options.show_hash
+    @hyperlink_all = hyperlink_all
+    @show_hash     = show_hash
+    @autolink_excluded_words = autolink_excluded_words
+    @warn_missing_rdoc_ref = warn_missing_rdoc_ref
 
     @cross_reference = RDoc::CrossReference.new @context
   end
@@ -48,7 +52,7 @@ def init_link_notation_regexp_handlings
 
     # The crossref must be linked before tidylink because Klass.method[:sym]
     # will be processed as a tidylink first and will be broken.
-    crossref_re = @options.hyperlink_all ? ALL_CROSSREF_REGEXP : CROSSREF_REGEXP
+    crossref_re = @hyperlink_all ? ALL_CROSSREF_REGEXP : CROSSREF_REGEXP
     @markup.add_regexp_handling crossref_re, :CROSSREF
   end
 
@@ -83,7 +87,7 @@ def cross_reference(name, text = nil, code = true, rdoc_ref: false)
 
   def handle_regexp_CROSSREF(name)
     return convert_string(name) if in_tidylink_label?
-    return name if @options.autolink_excluded_words&.include?(name)
+    return name if @autolink_excluded_words&.include?(name)
 
     return name if name =~ /@[\w-]+\.[\w-]/ # labels that look like emails
 
@@ -159,7 +163,7 @@ def link(name, text, code = true, rdoc_ref: false)
 
     case ref
     when String then
-      if rdoc_ref && @options.warn_missing_rdoc_ref
+      if rdoc_ref && @warn_missing_rdoc_ref
         puts "#{@from_path}: `rdoc-ref:#{name}` can't be resolved for `#{text}`"
       end
       ref
@@ -224,7 +228,7 @@ def apply_tidylink_label_special_handling(label, url)
   def tt_cross_reference(code)
     return if in_tidylink_label?
 
-    crossref_regexp = @options.hyperlink_all ? ALL_CROSSREF_REGEXP : CROSSREF_REGEXP
+    crossref_regexp = @hyperlink_all ? ALL_CROSSREF_REGEXP : CROSSREF_REGEXP
     match = crossref_regexp.match(code)
     return unless match && match.begin(1).zero?
     return unless match.post_match.match?(/\A[[:punct:]\s]*\z/)

lib/rdoc/markup/to_html_snippet.rb

@@ -34,8 +34,8 @@ class RDoc::Markup::ToHtmlSnippet < RDoc::Markup::ToHtml
   # next word boundary after the given number of +characters+ or +paragraphs+
   # of text have been encountered.
 
-  def initialize(options, characters = 100, paragraphs = 3)
-    super options
+  def initialize(characters = 100, paragraphs = 3)
+    super()
 
     @character_limit = characters
     @paragraph_limit = paragraphs

lib/rdoc/markup/to_joined_paragraph.rb

@@ -10,7 +10,7 @@
 class RDoc::Markup::ToJoinedParagraph < RDoc::Markup::Formatter
 
   def initialize # :nodoc:
-    super nil
+    super
   end
 
   def start_accepting # :nodoc:

lib/rdoc/markup/to_label.rb

@@ -15,7 +15,7 @@ class RDoc::Markup::ToLabel < RDoc::Markup::Formatter
   # Creates a new formatter that will output HTML-safe labels
 
   def initialize
-    super nil
+    super
 
     @markup.add_regexp_handling RDoc::CrossReference::CROSSREF_REGEXP, :CROSSREF
 

lib/rdoc/markup/to_rdoc.rb

@@ -53,7 +53,7 @@ class RDoc::Markup::ToRdoc < RDoc::Markup::Formatter
   # Creates a new formatter that will output (mostly) \RDoc markup
 
   def initialize
-    super nil
+    super
 
     @markup.add_regexp_handling(/\\\S/, :SUPPRESSED_CROSSREF)
     @width = 78