Fix false-positives that non Rails formats are offended on Rails/ToSWithArgument

Author: r7kamura

changelog/fix_false_positives_that_non_rails_formats.md

@@ -0,0 +1 @@
+* [#869](https://github.com/rubocop/rubocop-rails/pull/869): Fix false-positives that non Rails formats are offended on `Rails/ToSWithArgument`. ([@r7kamura][])

lib/rubocop/cop/rails/to_s_with_argument.rb

@@ -21,20 +21,57 @@ class ToSWithArgument < Base
         extend AutoCorrector
         extend TargetRailsVersion
 
+        # These types are defined by the following files in ActiveSupport:
+        #   lib/active_support/core_ext/array/conversions.rb
+        #   lib/active_support/core_ext/date/conversions.rb
+        #   lib/active_support/core_ext/date_time/conversions.rb
+        #   lib/active_support/core_ext/numeric/conversions.rb
+        #   lib/active_support/core_ext/range/conversions.rb
+        #   lib/active_support/core_ext/time/conversions.rb
+        #   lib/active_support/time_with_zone.rb
+        EXTENDED_FORMAT_TYPES = Set.new(
+          %i[
+            currency
+            db
+            delimited
+            human
+            human_size
+            inspect
+            iso8601
+            long
+            long_ordinal
+            nsec
+            number
+            percentage
+            phone
+            rfc822
+            rounded
+            short
+            time
+            usec
+          ]
+        )
+
         MSG = 'Use `to_formatted_s` instead.'
 
         RESTRICT_ON_SEND = %i[to_s].freeze
 
         minimum_target_rails_version 7.0
 
         def on_send(node)
-          return if node.arguments.empty?
+          return unless rails_extended_to_s?(node)
 
           add_offense(node.loc.selector) do |corrector|
             corrector.replace(node.loc.selector, 'to_formatted_s')
           end
         end
         alias on_csend on_send
+
+        private
+
+        def rails_extended_to_s?(node)
+          node.first_argument&.sym_type? && EXTENDED_FORMAT_TYPES.include?(node.first_argument.value)
+        end
       end
     end
   end

spec/rubocop/cop/rails/to_s_with_argument_spec.rb

@@ -9,6 +9,14 @@
     end
   end
 
+  context 'with unrelated argument' do
+    it 'does not register an offense' do
+      expect_no_offenses(<<~RUBY)
+        10.to_s(2)
+      RUBY
+    end
+  end
+
   context 'with argument' do
     it 'registers an offense' do
       expect_offense(<<~RUBY)