Add more type signatures.

Library/.rubocop.yml

@@ -297,15 +297,9 @@ Sorbet/ConstantsFromStrings:
 Style/AccessModifierDeclarations:
   Enabled: false
 
-# don't group nicely documented or private attr_readers
+# Conflicts with type signatures on `attr_*`s.
 Style/AccessorGrouping:
-  Exclude:
-    - 'Homebrew/formula.rb'
-    - 'Homebrew/formulary.rb'
-    - 'Homebrew/migrator.rb'
-    - 'Homebrew/resource.rb'
-    - 'Homebrew/system_command.rb'
-    - 'Homebrew/tap.rb'
+  Enabled: false
 
 # make rspec formatting more flexible
 Style/BlockDelimiters:

Library/Homebrew/bintray.rb

@@ -8,13 +8,16 @@
 #
 # @api private
 class Bintray
+  extend T::Sig
+
   include Context
 
   API_URL = "https://api.bintray.com"
 
   class Error < RuntimeError
   end
 
+  sig { returns(String) }
   def inspect
     "#<Bintray: org=#{@bintray_org}>"
   end

Library/Homebrew/cask/artifact/abstract_artifact.rb

@@ -7,6 +7,8 @@ module Artifact
     #
     # @api private
     class AbstractArtifact
+      extend T::Sig
+
       include Comparable
       extend Predicable
 
@@ -132,6 +134,7 @@ def config
         cask.config
       end
 
+      sig { returns(String) }
       def to_s
         "#{summarize} (#{self.class.english_name})"
       end

Library/Homebrew/cask/artifact/abstract_uninstall.rb

@@ -15,6 +15,8 @@ module Artifact
     #
     # @api private
     class AbstractUninstall < AbstractArtifact
+      extend T::Sig
+
       ORDERED_DIRECTIVES = [
         :early_script,
         :launchctl,
@@ -53,6 +55,7 @@ def to_h
         directives.to_h
       end
 
+      sig { returns(String) }
       def summarize
         to_h.flat_map { |key, val| Array(val).map { |v| "#{key.inspect} => #{v.inspect}" } }.join(", ")
       end
@@ -128,6 +131,7 @@ def running_processes(bundle_id)
           end
       end
 
+      sig { returns(String) }
       def automation_access_instructions
         "Enable Automation Access for “Terminal > System Events” in " \
         "“System Preferences > Security > Privacy > Automation” if you haven't already."

Library/Homebrew/cask/artifact/artifact.rb

@@ -12,6 +12,9 @@ module Artifact
     #
     # @api private
     class Artifact < Moved
+      extend T::Sig
+
+      sig { returns(String) }
       def self.english_name
         "Generic Artifact"
       end

Library/Homebrew/cask/artifact/mdimporter.rb

@@ -9,6 +9,9 @@ module Artifact
     #
     # @api private
     class Mdimporter < Moved
+      extend T::Sig
+
+      sig { returns(String) }
       def self.english_name
         "Spotlight metadata importer"
       end

Library/Homebrew/cask/artifact/moved.rb

@@ -9,6 +9,9 @@ module Artifact
     #
     # @api private
     class Moved < Relocated
+      extend T::Sig
+
+      sig { returns(String) }
       def self.english_description
         "#{english_name}s"
       end

Library/Homebrew/cask/artifact/prefpane.rb

@@ -9,6 +9,9 @@ module Artifact
     #
     # @api private
     class Prefpane < Moved
+      extend T::Sig
+
+      sig { returns(String) }
       def self.english_name
         "Preference Pane"
       end

Library/Homebrew/cask/artifact/qlplugin.rb

@@ -9,6 +9,9 @@ module Artifact
     #
     # @api private
     class Qlplugin < Moved
+      extend T::Sig
+
+      sig { returns(String) }
       def self.english_name
         "QuickLook Plugin"
       end

Library/Homebrew/cask/artifact/relocated.rb

@@ -12,6 +12,8 @@ module Artifact
     #
     # @api private
     class Relocated < AbstractArtifact
+      extend T::Sig
+
       def self.from_args(cask, *args)
         source_string, target_hash = args
 
@@ -49,6 +51,7 @@ def to_a
         end
       end
 
+      sig { returns(String) }
       def summarize
         target_string = @target_string.empty? ? "" : " -> #{@target_string}"
         "#{@source_string}#{target_string}"

Library/Homebrew/cask/artifact/stage_only.rb

@@ -9,16 +9,20 @@ module Artifact
     #
     # @api private
     class StageOnly < AbstractArtifact
+      extend T::Sig
+
       def self.from_args(cask, *args)
         raise CaskInvalidError.new(cask.token, "'stage_only' takes only a single argument: true") if args != [true]
 
         new(cask)
       end
 
+      sig { returns(T::Array[T::Boolean]) }
       def to_a
         [true]
       end
 
+      sig { returns(String) }
       def summarize
         "true"
       end

Library/Homebrew/cask/artifact/suite.rb

@@ -9,10 +9,14 @@ module Artifact
     #
     # @api private
     class Suite < Moved
+      extend T::Sig
+
+      sig { returns(String) }
       def self.english_name
         "App Suite"
       end
 
+      sig { returns(Symbol) }
       def self.dirmethod
         :appdir
       end

Library/Homebrew/cask/artifact/symlinked.rb

@@ -9,10 +9,14 @@ module Artifact
     #
     # @api private
     class Symlinked < Relocated
+      extend T::Sig
+
+      sig { returns(String) }
       def self.link_type_english_name
         "Symlink"
       end
 
+      sig { returns(String) }
       def self.english_description
         "#{english_name} #{link_type_english_name}s"
       end

Library/Homebrew/cask/audit.rb

@@ -13,6 +13,8 @@ module Cask
   #
   # @api private
   class Audit
+    extend T::Sig
+
     extend Predicable
 
     attr_reader :cask, :download
@@ -117,6 +119,7 @@ def result
       end
     end
 
+    sig { returns(String) }
     def summary
       summary = ["audit for #{cask}: #{result}"]
 
@@ -416,6 +419,7 @@ def core_formula_names
       core_tap.formula_names
     end
 
+    sig { returns(String) }
     def core_formula_url
       "#{core_tap.default_remote}/blob/HEAD/Formula/#{cask.token}.rb"
     end

Library/Homebrew/cask/cask.rb

@@ -12,6 +12,8 @@ module Cask
   #
   # @api private
   class Cask
+    extend T::Sig
+
     extend Enumerable
     extend Forwardable
     extend Searchable
@@ -64,6 +66,7 @@ def config=(config)
       define_method(method_name) { |&block| @dsl.send(method_name, &block) }
     end
 
+    sig { returns(T::Array[[String, String]]) }
     def timestamped_versions
       Pathname.glob(metadata_timestamped_path(version: "*", timestamp: "*"))
               .map { |p| p.relative_path_from(p.parent.parent) }
@@ -89,6 +92,7 @@ def installed?
       !versions.empty?
     end
 
+    sig { returns(T.nilable(Time)) }
     def install_time
       _, time = timestamped_versions.last
       return unless time

Library/Homebrew/cask/cask_loader.rb

@@ -90,6 +90,8 @@ def cask(header_token, **options, &block)
 
     # Loads a cask from a URI.
     class FromURILoader < FromPathLoader
+      extend T::Sig
+
       def self.can_load?(ref)
         uri_regex = ::URI::DEFAULT_PARSER.make_regexp
         return false unless ref.to_s.match?(Regexp.new("\\A#{uri_regex.source}\\Z", uri_regex.options))
@@ -103,6 +105,7 @@ def self.can_load?(ref)
 
       attr_reader :url
 
+      sig { params(url: T.any(URI::Generic, String)).void }
       def initialize(url)
         @url = URI(url)
         super Cache.path/File.basename(@url.path)
@@ -177,10 +180,13 @@ def load(config:)
 
     # Pseudo-loader which raises an error when trying to load the corresponding cask.
     class NullLoader < FromPathLoader
+      extend T::Sig
+
       def self.can_load?(*)
         true
       end
 
+      sig { params(ref: T.any(String, Pathname)).void }
       def initialize(ref)
         token = File.basename(ref, ".rb")
         super CaskLoader.default_path(token)

Library/Homebrew/cask/cmd.rb

@@ -38,6 +38,8 @@ module Cask
   #
   # @api private
   class Cmd
+    extend T::Sig
+
     include Context
 
     ALIASES = {
@@ -61,6 +63,7 @@ class Cmd
       Cmd::Upgrade   => "brew upgrade --cask",
     }.freeze
 
+    sig { returns(String) }
     def self.description
       max_command_length = Cmd.commands.map(&:length).max
 

Library/Homebrew/cask/cmd/--cache.rb

@@ -7,18 +7,24 @@ class Cmd
     #
     # @api private
     class Cache < AbstractCommand
+      extend T::Sig
+
+      sig { override.returns(T.nilable(T.any(Integer, Symbol))) }
       def self.min_named
         :cask
       end
 
+      sig { returns(String) }
       def self.description
         "Display the file used to cache a <cask>."
       end
 
+      sig { returns(String) }
       def self.command_name
         "--cache"
       end
 
+      sig { void }
       def run
         casks.each do |cask|
           puts self.class.cached_location(cask)

Library/Homebrew/cask/cmd/abstract_command.rb

@@ -9,16 +9,22 @@ class Cmd
     #
     # @api private
     class AbstractCommand
+      extend T::Sig
+      extend T::Helpers
+
       include Homebrew::Search
 
+      sig { returns(T.nilable(T.any(Integer, Symbol))) }
       def self.min_named
         nil
       end
 
+      sig { returns(T.nilable(Integer)) }
       def self.max_named
         nil
       end
 
+      sig { returns(String) }
       def self.banner_args
         if min_named == :cask && max_named != 1
           " <cask>"
@@ -29,6 +35,7 @@ def self.banner_args
         end
       end
 
+      sig { returns(String) }
       def self.banner_headline
         "`#{command_name}` [<options>]#{banner_args}"
       end
@@ -72,24 +79,29 @@ def self.parser(&block)
         end
       end
 
+      sig { returns(String) }
       def self.command_name
         @command_name ||= name.sub(/^.*:/, "").gsub(/(.)([A-Z])/, '\1_\2').downcase
       end
 
+      sig { returns(T::Boolean) }
       def self.abstract?
         name.split("::").last.match?(/^Abstract[^a-z]/)
       end
 
+      sig { returns(T::Boolean) }
       def self.visible?
         true
       end
 
+      sig { returns(String) }
       def self.help
         parser.generate_help_text
       end
 
+      sig { returns(String) }
       def self.short_description
-        description.split(".").first
+        description[/\A[^.]*\./]
       end
 
       def self.run(*args)

Library/Homebrew/cask/cmd/abstract_internal_command.rb

@@ -7,10 +7,14 @@ class Cmd
     #
     # @api private
     class AbstractInternalCommand < AbstractCommand
+      extend T::Sig
+
+      sig { returns(String) }
       def self.command_name
         super.sub(/^internal_/i, "_")
       end
 
+      sig { returns(T::Boolean) }
       def self.visible?
         false
       end