Handle recursive keys in strong parameters expect

Fixes rubocop#1429

Use a recursive approach to autocorrect nested parameters
- Top level hash keys do not get replaced by `[]`
- Hash values that are hashes get replaced by `[]`
- Arrays get replaced by double brackets `[[]]`

Author: chaadow

changelog/fix_strong_parameters_expect_recursive_autocorrect.md

@@ -0,0 +1 @@
+* [#1429](https://github.com/rubocop/rubocop-rails/issues/1429): Fix a wrong autocorrect for `Rails/StrongParametersExpect` when hashes and arrays are present. ([@chaadow][])

lib/rubocop/cop/rails/strong_parameters_expect.rb

@@ -62,8 +62,13 @@ def on_send(node)
             corrector.remove(require_method.receiver.source_range.end.join(require_method.source_range.end))
             corrector.replace(permit_method.loc.selector, 'expect')
             if replace_argument
-              corrector.insert_before(permit_method.first_argument, "#{require_key(require_method)}[")
-              corrector.insert_after(permit_method.last_argument, ']')
+              transformed_arguments = permit_method.arguments.map { |arg| recursive_transform(arg) }.join(', ')
+              transformed_string = "#{require_key(require_method)}[#{transformed_arguments}])"
+
+              args_range = permit_method.source_range.with(
+                begin_pos: permit_method.first_argument.source_range.begin_pos
+              )
+              corrector.replace(args_range, transformed_string)
             end
           end
 
@@ -80,11 +85,35 @@ def offense_range(method_node, node)
 
         def expect_method(require_method, permit_method)
           require_key = require_key(require_method)
-          permit_args = permit_method.arguments.map(&:source).join(', ')
 
-          arguments = "#{require_key}[#{permit_args}]"
+          permit_args = permit_method.arguments.map { |arg| recursive_transform(arg) }.join(', ')
+
+          "expect(#{require_key}[#{permit_args}])"
+        end
 
-          "expect(#{arguments})"
+        def recursive_transform(node, top_level: true)
+          case node.type
+          when :hash
+            elements = hash_elements_from_node(node)
+            if top_level
+              elements.join(', ')
+            else
+              elements.empty? ? '{}' : "[#{elements.join(', ')}]"
+            end
+          when :array
+            elements = node.children.map { |child| recursive_transform(child, top_level: false) }
+            elements.empty? ? elements : "[[#{elements.join(', ')}]]"
+          else
+            node.source
+          end
+        end
+
+        def hash_elements_from_node(node)
+          node.pairs.map do |pair|
+            key = pair.key.source
+            value = recursive_transform(pair.value, top_level: false)
+            "#{key}: #{value}"
+          end
         end
 
         def require_key(require_method)

spec/rubocop/cop/rails/strong_parameters_expect_spec.rb

@@ -13,6 +13,20 @@
       RUBY
     end
 
+    it 'registers an offense when using
+  `params.require(:user).permit(:salary, :employees_count, rows_prices:
+ { row_total_one_post: [:price, :cell_id], row_total_all_posts: [:price, :cell_id]
+ }, data: {}, another_array: [:name])`' do
+      expect_offense(<<~RUBY)
+        params.require(:user).permit(:salary, :posts_count, rows_prices: { row_total_one_post: [:price, :cell_id], row_total_all_posts: [:price, :cell_id] }, data: {}, another_array: [:name])
+               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Use `expect(user: [:salary, :posts_count, rows_prices: [row_total_one_post: [[:price, :cell_id]], row_total_all_posts: [[:price, :cell_id]]], data: {}, another_array: [[:name]]])` instead.
+      RUBY
+
+      expect_correction(<<~RUBY)
+        params.expect(user: [:salary, :posts_count, rows_prices: [row_total_one_post: [[:price, :cell_id]], row_total_all_posts: [[:price, :cell_id]]], data: {}, another_array: [[:name]]])
+      RUBY
+    end
+
     it 'registers an offense when using `params&.require(:user)&.permit(:name, :age)`' do
       expect_offense(<<~RUBY)
         params&.require(:user)&.permit(:name, :age)
@@ -92,9 +106,7 @@
 
       expect_correction(<<~RUBY)
         params.expect(
-          user: [:name, # comment
-          :age] # comment
-        )
+          user: [:name, :age])
       RUBY
     end