Improve rubocop setup

.generated_files_rubocop.yml

@@ -0,0 +1,12 @@
+# This rubocop configuration is ONLY for the generated files (listed in Rakefile). It is not meant to be used for RDoc's
+# source code.
+# The purpose of this file is to ensure the generated files don't have trailing whitespace or empty lines, which could
+# be a problem for ruby/ruby's CI
+AllCops:
+  TargetRubyVersion: 3.3
+  DisabledByDefault: true
+
+Layout/TrailingWhitespace:
+  Enabled: true
+Layout/TrailingEmptyLines:
+  Enabled: true

.github/workflows/test.yml

@@ -45,5 +45,17 @@ jobs:
         RUBYOPT: --enable-frozen_string_literal
     - if: ${{ matrix.ruby == 'head' && startsWith(matrix.os, 'ubuntu') }}
       run: bundle exec rake rdoc
-    - if: ${{ matrix.ruby == 'head' && startsWith(matrix.os, 'ubuntu') }}
-      run: bundle exec rake rubocop
+  lint:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Set up Ruby
+        uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: "3.3"
+          bundler-cache: true
+      - name: Run rubocop
+        run: bundle exec rubocop
+        # Just to make sure the format_generated_files task is working
+      - name: Sanity check for the format_generated_files task
+        run: bundle exec rake generate format_generated_files

.rubocop.yml

@@ -1,10 +1,19 @@
 AllCops:
-  TargetRubyVersion: 2.6
+  TargetRubyVersion: 3.0
   DisabledByDefault: true
-  Exclude:
-    - rdoc.gemspec
+  SuggestExtensions: false
 
 Layout/TrailingWhitespace:
   Enabled: true
+
 Layout/TrailingEmptyLines:
   Enabled: true
+
+Layout/SpaceAroundKeyword:
+  Enabled: true
+
+Layout/SpaceBeforeComma:
+  Enabled: true
+
+Layout/SpaceAfterComma:
+  Enabled: true

Rakefile

@@ -105,8 +105,8 @@ begin
   require 'rubocop/rake_task'
 rescue LoadError
 else
-  RuboCop::RakeTask.new(:rubocop) do |t|
-    t.options = [*parsed_files]
+  RuboCop::RakeTask.new(:format_generated_files) do |t|
+    t.options = parsed_files + ["--config=.generated_files_rubocop.yml"]
   end
-  task :build => [:generate, "rubocop:autocorrect"]
+  task :build => [:generate, "format_generated_files:autocorrect"]
 end

lib/rdoc/code_object/alias.rb

@@ -70,7 +70,7 @@ def full_old_name
   # HTML id-friendly version of +#new_name+.
 
   def html_name
-    CGI.escape(@new_name.gsub('-', '-2D')).gsub('%','-').sub(/^-/, '')
+    CGI.escape(@new_name.gsub('-', '-2D')).gsub('%', '-').sub(/^-/, '')
   end
 
   def inspect # :nodoc:

lib/rdoc/code_object/method_attr.rb

@@ -268,8 +268,8 @@ def block_params=(value)
       when 'const_get' then 'const'
       when 'new' then
         $1.split('::').last.  # ClassName => class_name
-          gsub(/([A-Z]+)([A-Z][a-z])/,'\1_\2').
-          gsub(/([a-z\d])([A-Z])/,'\1_\2').
+          gsub(/([A-Z]+)([A-Z][a-z])/, '\1_\2').
+          gsub(/([a-z\d])([A-Z])/, '\1_\2').
           downcase
       else
         $2
@@ -291,7 +291,7 @@ def block_params=(value)
   def html_name
     require 'cgi/util'
 
-    CGI.escape(@name.gsub('-', '-2D')).gsub('%','-').sub(/^-/, '')
+    CGI.escape(@name.gsub('-', '-2D')).gsub('%', '-').sub(/^-/, '')
   end
 
   ##

lib/rdoc/code_object/top_level.rb

@@ -183,8 +183,8 @@ def inspect # :nodoc:
     "#<%s:0x%x %p modules: %p classes: %p>" % [
       self.class, object_id,
       base_name,
-      @modules.map { |n,m| m },
-      @classes.map { |n,c| c }
+      @modules.map { |n, m| m },
+      @classes.map { |n, c| c }
     ]
   end
 
@@ -254,8 +254,8 @@ def pretty_print q # :nodoc:
       q.text "base name: #{base_name.inspect}"
       q.breakable
 
-      items = @modules.map { |n,m| m }
-      items.concat @modules.map { |n,c| c }
+      items = @modules.map { |n, m| m }
+      items.concat @modules.map { |n, c| c }
       q.seplist items do |mod| q.pp mod end
     end
   end

lib/rdoc/generator/pot/message_extractor.rb

@@ -29,7 +29,7 @@ def extract_from_klass klass
     extract_text(klass.comment_location, klass.full_name)
 
     klass.each_section do |section, constants, attributes|
-      extract_text(section.title ,"#{klass.full_name}: section title")
+      extract_text(section.title, "#{klass.full_name}: section title")
       section.comments.each do |comment|
         extract_text(comment, "#{klass.full_name}: #{section.title}")
       end

lib/rdoc/markup/attribute_manager.rb

@@ -260,7 +260,7 @@ def unmask_protected_sequences
 
   def add_word_pair(start, stop, name, exclusive = false)
     raise ArgumentError, "Word flags may not start with '<'" if
-      start[0,1] == '<'
+      start[0, 1] == '<'
 
     bitmap = @attributes.bitmap_for name
 
@@ -271,7 +271,7 @@ def add_word_pair(start, stop, name, exclusive = false)
       @word_pair_map[pattern] = bitmap
     end
 
-    @protectable << start[0,1]
+    @protectable << start[0, 1]
     @protectable.uniq!
 
     @exclusive_bitmap |= bitmap if exclusive

lib/rdoc/markup/to_bs.rb

@@ -24,7 +24,7 @@ def initialize markup = nil
   def init_tags
     add_tag :BOLD, '+b', '-b'
     add_tag :EM,   '+_', '-_'
-    add_tag :TT,   ''  , ''   # we need in_tt information maintained
+    add_tag :TT,   '', ''   # we need in_tt information maintained
   end
 
   ##

lib/rdoc/options.rb

@@ -683,7 +683,7 @@ def parse argv
 
       EOF
 
-      parsers = Hash.new { |h,parser| h[parser] = [] }
+      parsers = Hash.new { |h, parser| h[parser] = [] }
 
       RDoc::Parser.parsers.each do |regexp, parser|
         parsers[parser.name.sub('RDoc::Parser::', '')] << regexp.source

lib/rdoc/parser/c.rb

@@ -440,7 +440,7 @@ def do_constants
   # Scans #content for rb_include_module
 
   def do_includes
-    @content.scan(/rb_include_module\s*\(\s*(\w+?),\s*(\w+?)\s*\)/) do |c,m|
+    @content.scan(/rb_include_module\s*\(\s*(\w+?),\s*(\w+?)\s*\)/) do |c, m|
       next unless cls = @classes[c]
       m = @known_classes[m] || m
 

lib/rdoc/parser/changelog.rb

@@ -193,7 +193,7 @@ class << self; prepend Git; end
 
     entries << [entry_name, entry_body] if entry_name
 
-    entries.reject! do |(entry,_)|
+    entries.reject! do |(entry, _)|
       entry == nil
     end