Clean up files that use to include cachable

These were changed to extend to make it easier to determine
where the classes come to in the extended callback but that
means that the file is somewhat inconsistent. On the one
hand we're using class methods and on the other we're extend
self. This cleans that up but now the diff is atrocious and
the blame is even worse. Oh well...

Library/Homebrew/api/cask.rb

@@ -12,16 +12,15 @@ module Homebrew
     module Cask
       extend Cachable
 
-      class << self
+      private_class_method :cache
-        private :cache
 
       sig { params(token: String).returns(Hash) }
-        def fetch(token)
+      def self.fetch(token)
         Homebrew::API.fetch "cask/#{token}.json"
       end
 
       sig { params(cask: ::Cask::Cask).returns(::Cask::Cask) }
-        def source_download(cask)
+      def self.source_download(cask)
         path = cask.ruby_source_path.to_s || "Casks/#{cask.token}.rb"
         sha256 = cask.ruby_source_checksum[:sha256]
         checksum = Checksum.new(sha256) if sha256
@@ -42,7 +41,7 @@ module Homebrew
       end
 
       sig { returns(T::Boolean) }
-        def download_and_cache_data!
+      def self.download_and_cache_data!
         json_casks, updated = Homebrew::API.fetch_json_api_file "cask.jws.json"
 
         cache["renames"] = {}
@@ -58,10 +57,10 @@ module Homebrew
 
         updated
       end
-        private :download_and_cache_data!
+      private_class_method :download_and_cache_data!
 
       sig { returns(T::Hash[String, Hash]) }
-        def all_casks
+      def self.all_casks
         unless cache.key?("casks")
           json_updated = download_and_cache_data!
           write_names(regenerate: json_updated)
@@ -71,7 +70,7 @@ module Homebrew
       end
 
       sig { returns(T::Hash[String, String]) }
-        def all_renames
+      def self.all_renames
         unless cache.key?("renames")
           json_updated = download_and_cache_data!
           write_names(regenerate: json_updated)
@@ -81,12 +80,11 @@ module Homebrew
       end
 
       sig { params(regenerate: T::Boolean).void }
-        def write_names(regenerate: false)
+      def self.write_names(regenerate: false)
         download_and_cache_data! unless cache.key?("casks")
 
         Homebrew::API.write_names_file(all_casks.keys, "cask", regenerate: regenerate)
       end
     end
   end
-  end
 end

Library/Homebrew/api/formula.rb

@@ -12,16 +12,15 @@ module Homebrew
     module Formula
       extend Cachable
 
-      class << self
+      private_class_method :cache
-        private :cache
 
       sig { params(name: String).returns(Hash) }
-        def fetch(name)
+      def self.fetch(name)
         Homebrew::API.fetch "formula/#{name}.json"
       end
 
       sig { params(formula: ::Formula).returns(::Formula) }
-        def source_download(formula)
+      def self.source_download(formula)
         path = formula.ruby_source_path || "Formula/#{formula.name}.rb"
         git_head = formula.tap_git_head || "HEAD"
         tap = formula.tap&.full_name || "Homebrew/homebrew-core"
@@ -39,7 +38,7 @@ module Homebrew
       end
 
       sig { returns(T::Boolean) }
-        def download_and_cache_data!
+      def self.download_and_cache_data!
         json_formulae, updated = Homebrew::API.fetch_json_api_file "formula.jws.json"
 
         cache["aliases"] = {}
@@ -57,10 +56,10 @@ module Homebrew
 
         updated
       end
-        private :download_and_cache_data!
+      private_class_method :download_and_cache_data!
 
       sig { returns(T::Hash[String, Hash]) }
-        def all_formulae
+      def self.all_formulae
         unless cache.key?("formulae")
           json_updated = download_and_cache_data!
           write_names_and_aliases(regenerate: json_updated)
@@ -70,7 +69,7 @@ module Homebrew
       end
 
       sig { returns(T::Hash[String, String]) }
-        def all_aliases
+      def self.all_aliases
         unless cache.key?("aliases")
           json_updated = download_and_cache_data!
           write_names_and_aliases(regenerate: json_updated)
@@ -80,7 +79,7 @@ module Homebrew
       end
 
       sig { returns(T::Hash[String, String]) }
-        def all_renames
+      def self.all_renames
         unless cache.key?("renames")
           json_updated = download_and_cache_data!
           write_names_and_aliases(regenerate: json_updated)
@@ -90,7 +89,7 @@ module Homebrew
       end
 
       sig { params(regenerate: T::Boolean).void }
-        def write_names_and_aliases(regenerate: false)
+      def self.write_names_and_aliases(regenerate: false)
         download_and_cache_data! unless cache.key?("formulae")
 
         return unless Homebrew::API.write_names_file(all_formulae.keys, "formula", regenerate: regenerate)
@@ -103,5 +102,4 @@ module Homebrew
       end
     end
   end
-  end
 end

Library/Homebrew/readall.rb

@@ -10,17 +10,15 @@ require "system_command"
 # @api private
 module Readall
   extend Cachable
-
+  extend SystemCommand::Mixin
-  class << self
-    include SystemCommand::Mixin
 
   # TODO: remove this once the `MacOS` module is undefined on Linux
   MACOS_MODULE_REGEX = /\b(MacOS|OS::Mac)(\.|::)\b/
   private_constant :MACOS_MODULE_REGEX
 
-    private :cache
+  private_class_method :cache
 
-    def valid_ruby_syntax?(ruby_files)
+  def self.valid_ruby_syntax?(ruby_files)
     failed = T.let(false, T::Boolean)
     ruby_files.each do |ruby_file|
       # As a side effect, print syntax errors/warnings to `$stderr`.
@@ -29,7 +27,7 @@ module Readall
     !failed
   end
 
-    def valid_aliases?(alias_dir, formula_dir)
+  def self.valid_aliases?(alias_dir, formula_dir)
     return true unless alias_dir.directory?
 
     failed = T.let(false, T::Boolean)
@@ -50,7 +48,7 @@ module Readall
     !failed
   end
 
-    def valid_formulae?(tap, bottle_tag: nil)
+  def self.valid_formulae?(tap, bottle_tag: nil)
     cache[:valid_formulae] ||= {}
 
     success = T.let(true, T::Boolean)
@@ -83,11 +81,12 @@ module Readall
     success
   end
 
-    def valid_casks?(_tap, os_name: nil, arch: nil)
+  def self.valid_casks?(_tap, os_name: nil, arch: nil)
     true
   end
 
-    def valid_tap?(tap, aliases: false, no_simulate: false, os_arch_combinations: OnSystem::ALL_OS_ARCH_COMBINATIONS)
+  def self.valid_tap?(tap, aliases: false, no_simulate: false,
+                      os_arch_combinations: OnSystem::ALL_OS_ARCH_COMBINATIONS)
     success = true
 
     if aliases
@@ -113,9 +112,7 @@ module Readall
     success
   end
 
-    private
+  private_class_method def self.syntax_errors_or_warnings?(filename)
-
-    def syntax_errors_or_warnings?(filename)
     # Retrieve messages about syntax errors/warnings printed to `$stderr`.
     _, err, status = system_command(RUBY_PATH, args: ["-c", "-w", filename], print_stderr: false)
 
@@ -131,7 +128,6 @@ module Readall
     # warnings we also need to inspect the output to `$stderr`.
     !status.success? || !messages.chomp.empty?
   end
-  end
 end
 
 require "extend/os/readall"