Naming/MemoizedInstanceVariableName

Because renaming memoized instance variables can be potentially
dangerous, to address the Rubocop Naming/MemoizedInstanceVariableName
cop, this commit excludes existing violations while enabling the cop for
new code.

Author: mhashizume

.rubocop.yml

@@ -84,5 +84,13 @@ Naming/ConstantName:
 Naming/HeredocDelimiterNaming:
   Enabled: false
 
+# Exclude existing violations to avoid breaking changes
+Naming/MemoizedInstanceVariableName:
+  Exclude:
+    - 'lib/puppet/module_tool/applications/installer.rb'
+    - 'lib/puppet/pops/types/type_factory.rb'
+    - 'lib/puppet/provider/package/portage.rb'
+    - 'lib/puppet/resource.rb'
+
 Naming/MethodParameterName:
   Enabled: false

.rubocop_todo.yml

@@ -656,11 +656,6 @@ Naming/BlockParameterName:
     - 'lib/puppet/util/windows/daemon.rb'
     - 'lib/puppet/util/windows/user.rb'
 
-# Configuration parameters: EnforcedStyleForLeadingUnderscores.
-# SupportedStylesForLeadingUnderscores: disallowed, required, optional
-Naming/MemoizedInstanceVariableName:
-  Enabled: false
-
 # Configuration parameters: EnforcedStyle, AllowedPatterns, IgnoredPatterns.
 # SupportedStyles: snake_case, camelCase
 Naming/MethodName:

lib/puppet/etc.rb

@@ -132,6 +132,7 @@ def group
     # these fields as well. API compatible with Etc::Passwd. Because Struct.new
     # defines a new Class object, we memoize to avoid superfluous extra Class
     # instantiations.
+    # rubocop:disable Naming/MemoizedInstanceVariableName
     def puppet_etc_passwd_class
       @password_class ||= Struct.new(*Etc::Passwd.members, *Etc::Passwd.members.map { |member| "canonical_#{member}".to_sym })
     end
@@ -145,6 +146,7 @@ def puppet_etc_passwd_class
     def puppet_etc_group_class
       @group_class ||= Struct.new(*Etc::Group.members, *Etc::Group.members.map { |member| "canonical_#{member}".to_sym })
     end
+    # rubocop:enable Naming/MemoizedInstanceVariableName
 
     # Utility method for overriding the String values of a struct returned by
     # the Etc module to UTF-8. Structs returned by the ruby Etc module contain

lib/puppet/forge.rb

@@ -195,6 +195,7 @@ def prepare
     # Obtain a suitable temporary path for unpacking tarballs
     #
     # @return [Pathname] path to temporary unpacking location
+    # rubocop:disable Naming/MemoizedInstanceVariableName
     def tmpdir
       @dir ||= Dir.mktmpdir(name, Puppet::Forge::Cache.base_path)
     end
@@ -204,6 +205,7 @@ def tmpfile
         f.binmode
       end
     end
+    # rubocop:enable Naming/MemoizedInstanceVariableName
 
     def download(uri, destination)
       response = @source.make_http_request(uri, destination)

lib/puppet/module_tool/applications/unpacker.rb

@@ -93,9 +93,11 @@ def move_into(dir)
       #
       # @api private
       # @return [String] path to temporary unpacking location
+      # rubocop:disable Naming/MemoizedInstanceVariableName
       def tmpdir
         @dir ||= Dir.mktmpdir('tmp', Puppet::Forge::Cache.base_path)
       end
+      # rubocop:enable Naming/MemoizedInstanceVariableName
     end
   end
 end

lib/puppet/module_tool/applications/upgrader.rb

@@ -220,13 +220,15 @@ def installed_release.priority
       end
 
       private
+      # rubocop:disable Naming/MemoizedInstanceVariableName
       def module_repository
         @repo ||= Puppet::Forge.new(Puppet[:module_repository])
       end
 
       def installed_modules_source
         @installed ||= Puppet::ModuleTool::InstalledModules.new(@environment)
       end
+      # rubocop:enable Naming/MemoizedInstanceVariableName
 
       def installed_modules
         installed_modules_source.modules

lib/puppet/module_tool/local_tarball.rb

@@ -76,9 +76,11 @@ def prepare
     # Obtain a suitable temporary path for unpacking tarballs
     #
     # @return [String] path to temporary unpacking location
+    # rubocop:disable Naming/MemoizedInstanceVariableName
     def tmpdir
       @dir ||= Dir.mktmpdir('local-tarball', Puppet::Forge::Cache.base_path)
     end
+    # rubocop:enable Naming/MemoizedInstanceVariableName
 
     def unpack(file, destination)
       begin

lib/puppet/pal/json_catalog_encoder.rb

@@ -62,11 +62,12 @@ def encode_resource(type, title)
   # or the catalog itself if filtering was not needed.
   # The result is cached.
   # @api private
-  #
+  # rubocop:disable Naming/MemoizedInstanceVariableName
   def possibly_filtered_catalog
     @filtered ||= (exclude_virtual ? catalog.filter { |r| r.virtual? } : catalog)
   end
   private :possibly_filtered_catalog
+  # rubocop:enable Naming/MemoizedInstanceVariableName
 end
 end
 end

lib/puppet/pops/adaptable.rb

@@ -188,10 +188,11 @@ def self.type_name
     # Adapter#instance_var_name and then cached.
     # @return [String] the instance variable name for _name_
     # @api private
-    #
+    # rubocop:disable Naming/MemoizedInstanceVariableName
     def self.self_attr_name
       @attr_name_sym ||= :"@#{instance_var_name(type_name)}"
     end
+    # rubocop:enable Naming/MemoizedInstanceVariableName
   end
 end
 end

lib/puppet/pops/evaluator/closure.rb

@@ -135,9 +135,11 @@ def return_type
   end
 
   # @api public
+  # rubocop:disable Naming/MemoizedInstanceVariableName
   def type
     @callable ||= create_callable_type
   end
+  # rubocop:enable Naming/MemoizedInstanceVariableName
 
   # @api public
   def params_struct