[Fix #9465] Update Metrics/ParameterLists to be able to write `MaxO…

…ptionalParameters` in rubocop_todo.yml.

changelog/fix_update_metricsparameterlists_to_be_able.md

@@ -0,0 +1 @@
+* [#9465](https://github.com/rubocop-hq/rubocop/issues/9465): Update `Metrics/ParameterLists` to be able to write `MaxOptionalParameters` in rubocop_todo.yml. ([@dvandersluis][])

lib/rubocop/cop/metrics/parameter_lists.rb

@@ -52,7 +52,7 @@ module Metrics
       #
       class ParameterLists < Base
         exclude_limit 'Max'
-
+        exclude_limit 'MaxOptionalParameters'
 
         MSG = 'Avoid parameter lists longer than %<max>d parameters. ' \
               '[%<count>d/%<max>d]'
@@ -71,7 +71,9 @@ def on_def(node)
             count: optargs.count
           )
 
-          add_offense(node, message: message)
+          add_offense(node, message: message) do
+            self.max_optional_parameters = optargs.count
+          end
         end
         alias on_defs on_def
 

spec/rubocop/cop/metrics/parameter_lists_spec.rb

@@ -66,10 +66,20 @@ def meth(a, b, c, d:, e:)
 
   it 'registers an offense when optargs count exceeds the maximum' do
     expect_offense(<<~RUBY)
+      def foo(a = 1, b = 2, c = 3, d = 4, e = 5, f = 6, g = 7)
+             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Avoid parameter lists longer than 4 parameters. [7/4]
+      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Method has too many optional parameters. [7/3]
+      end
+
       def foo(a = 1, b = 2, c = 3, d = 4)
       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Method has too many optional parameters. [4/3]
       end
     RUBY
+
+    expect(cop.config_to_allow_offenses[:exclude_limit]).to eq(
+      'Max' => 7,
+      'MaxOptionalParameters' => 7
+    )
   end
 
   it 'does not register an offense when method has allowed amount of optargs' do