Fix memory leak for ruby 3.2 (#882)

* Fix memory leak for ruby 3.2

* Add changelog

* Update documentation

CHANGELOG.md

@@ -9,6 +9,7 @@
 ### Bugs Fixed
 
 * [#874](https://github.com/toptal/chewy/pull/874): Fix `chewy:journal:clean` task for ruby 3.x. ([@muk-ai](https://github.com/muk-ai))
+* [#882](https://github.com/toptal/chewy/pull/882): Fix memory leak during `chewy:reset` for ruby 3.2 ([@konalegi](https://github.com/konalegi))
 
 ## 7.3.0 (2023-04-03)
 

README.md

@@ -503,7 +503,7 @@ class ProductsIndex < Chewy::Index
 
   field :name
   # simply use crutch-fetched data as a value:
-  field :category_names, value: ->(product, crutches) { crutches.categories[product.id] }
+  field :category_names, value: ->(product, crutches) { crutches[:categories][product.id] }
 end
 ```
 

lib/chewy/index/crutch.rb

@@ -12,13 +12,21 @@ class Crutches
         def initialize(index, collection)
           @index = index
           @collection = collection
-          @index._crutches.each_key do |name|
-            singleton_class.class_eval <<-METHOD, __FILE__, __LINE__ + 1
-              def #{name}
-                @#{name} ||= @index._crutches[:#{name}].call @collection
-              end
-            METHOD
-          end
+          @crutches_instances = {}
+        end
+
+        def method_missing(name, *, **)
+          return self[name] if @index._crutches.key?(name)
+
+          super
+        end
+
+        def respond_to_missing?(name, include_private = false)
+          @index._crutches.key?(name) || super
+        end
+
+        def [](name)
+          @crutches_instances[name] ||= @index._crutches[:"#{name}"].call(@collection)
         end
       end