Remove deprecated behavior to support referring to a singular association by its plural name

Author: rafaelfranca

activerecord/CHANGELOG.md

@@ -1,3 +1,11 @@
+*   Remove deprecated behavior to support referring to a singular association by its plural name.
+
+    *Rafael Mendonça França*
+
+*   Deprecate `Rails.application.config.active_record.allow_deprecated_singular_associations_name`
+
+    *Rafael Mendonça França*
+
 *   Remove deprecated support to passing `SchemaMigration` and `InternalMetadata` classes as arguments to
     `ActiveRecord::MigrationContext`.
 

activerecord/lib/active_record.rb

@@ -422,12 +422,19 @@ def self.global_executor_concurrency # :nodoc:
   singleton_class.attr_accessor :verify_foreign_keys_for_fixtures
   self.verify_foreign_keys_for_fixtures = false
 
-  ##
-  # :singleton-method: allow_deprecated_singular_associations_name
-  # If true, Rails will continue allowing plural association names in where clauses on singular associations
-  # This behavior will be removed in Rails 7.2.
-  singleton_class.attr_accessor :allow_deprecated_singular_associations_name
-  self.allow_deprecated_singular_associations_name = true
+  def self.allow_deprecated_singular_associations_name
+    ActiveRecord.deprecator.warn <<-WARNING.squish
+      `Rails.application.config.active_record.allow_deprecated_singular_associations_name`
+      is deprecated and will be removed in Rails 7.3.
+    WARNING
+  end
+
+  def self.allow_deprecated_singular_associations_name=(value)
+    ActiveRecord.deprecator.warn <<-WARNING.squish
+      `Rails.application.config.active_record.allow_deprecated_singular_associations_name`
+      is deprecated and will be removed in Rails 7.3.
+    WARNING
+  end
 
   singleton_class.attr_accessor :query_transformers
   self.query_transformers = []

activerecord/lib/active_record/table_metadata.rb

@@ -23,16 +23,7 @@ def has_column?(column_name)
     end
 
     def associated_with?(table_name)
-      if reflection = klass&._reflect_on_association(table_name)
-        reflection
-      elsif ActiveRecord.allow_deprecated_singular_associations_name && reflection = klass&._reflect_on_association(table_name.singularize)
-        ActiveRecord.deprecator.warn(<<~MSG)
-          Referring to a singular association (e.g. `#{reflection.name}`) by its plural name (e.g. `#{reflection.plural_name}`) is deprecated.
-
-          To convert this deprecation warning to an error and enable more performant behavior, set config.active_record.allow_deprecated_singular_associations_name = false.
-        MSG
-        reflection
-      end
+      klass&._reflect_on_association(table_name)
     end
 
     def associated_table(table_name)

guides/source/7_2_release_notes.md

@@ -134,8 +134,12 @@ Please refer to the [Changelog][active-record] for detailed changes.
 *   Remove deprecated support to passing `SchemaMigration` and `InternalMetadata` classes as arguments to
     `ActiveRecord::MigrationContext`.
 
+*   Remove deprecated behavior to support referring to a singular association by its plural name.
+
 ### Deprecations
 
+*   Deprecate `Rails.application.config.active_record.allow_deprecated_singular_associations_name`
+
 ### Notable changes
 
 Active Storage

guides/source/configuring.md

@@ -69,7 +69,6 @@ Below are the default values associated with each target version. In cases of co
 - [`config.action_dispatch.default_headers`](#config-action-dispatch-default-headers): `{ "X-Frame-Options" => "SAMEORIGIN", "X-XSS-Protection" => "0", "X-Content-Type-Options" => "nosniff", "X-Permitted-Cross-Domain-Policies" => "none", "Referrer-Policy" => "strict-origin-when-cross-origin" }`
 - [`config.action_text.sanitizer_vendor`](#config-action-text-sanitizer-vendor): `Rails::HTML::Sanitizer.best_supported_vendor`
 - [`config.action_view.sanitizer_vendor`](#config-action-view-sanitizer-vendor): `Rails::HTML::Sanitizer.best_supported_vendor`
-- [`config.active_record.allow_deprecated_singular_associations_name`](#config-active-record-allow-deprecated-singular-associations-name): `false`
 - [`config.active_record.before_committed_on_all_records`](#config-active-record-before-committed-on-all-records): `true`
 - [`config.active_record.belongs_to_required_validates_foreign_key`](#config-active-record-belongs-to-required-validates-foreign-key): `false`
 - [`config.active_record.commit_transaction_on_non_local_return`](#config-active-record-commit-transaction-on-non-local-return): `true`
@@ -1509,31 +1508,6 @@ For each process, Rails will create one global query executor that uses this man
 should be at least `thread_count + global_executor_concurrency + 1`. For example, if your web server has a maximum of 3 threads,
 and `global_executor_concurrency` is set to 4, then your pool size should be at least 8.
 
-#### `config.active_record.allow_deprecated_singular_associations_name`
-
-This enables deprecated behavior wherein singular associations can be referred to by their plural name in `where` clauses. Setting this to `false` is more performant.
-
-```ruby
-class Comment < ActiveRecord::Base
-  belongs_to :post
-end
-
-Comment.where(post: post_id).count  # => 5
-
-# When `allow_deprecated_singular_associations_name` is true:
-Comment.where(posts: post_id).count # => 5 (deprecation warning)
-
-# When `allow_deprecated_singular_associations_name` is false:
-Comment.where(posts: post_id).count # => error
-```
-
-The default value depends on the `config.load_defaults` target version:
-
-| Starting with version | The default value is |
-| --------------------- | -------------------- |
-| (original)            | `true`               |
-| 7.1                   | `false`              |
-
 #### `config.active_record.yaml_column_permitted_classes`
 
 Defaults to `[Symbol]`. Allows applications to include additional permitted classes to `safe_load()` on the `ActiveRecord::Coders::YAMLColumn`.

railties/lib/rails/application/configuration.rb

@@ -280,7 +280,6 @@ def load_defaults(target_version)
           if respond_to?(:active_record)
             active_record.run_commit_callbacks_on_first_saved_instances_in_transaction = false
             active_record.commit_transaction_on_non_local_return = true
-            active_record.allow_deprecated_singular_associations_name = false
             active_record.sqlite3_adapter_strict_strings_by_default = true
             active_record.query_log_tags_format = :sqlcommenter
             active_record.raise_on_assign_to_attr_readonly = true

railties/test/application/configuration_test.rb

@@ -2875,32 +2875,6 @@ def index
       assert_equal true, ActiveRecord.verify_foreign_keys_for_fixtures
     end
 
-    test "ActiveRecord.allow_deprecated_singular_associations_name is false by default for new apps" do
-      app "development"
-
-      assert_equal false, ActiveRecord.allow_deprecated_singular_associations_name
-    end
-
-    test "ActiveRecord.allow_deprecated_singular_associations_name is true by default for upgraded apps" do
-      remove_from_config '.*config\.load_defaults.*\n'
-
-      app "development"
-
-      assert_equal true, ActiveRecord.allow_deprecated_singular_associations_name
-    end
-
-    test "ActiveRecord.allow_deprecated_singular_associations_name can be configured via config.active_record.allow_deprecated_singular_associations_name" do
-      remove_from_config '.*config\.load_defaults.*\n'
-
-      app_file "config/initializers/new_framework_defaults_7_1.rb", <<-RUBY
-        Rails.application.config.active_record.allow_deprecated_singular_associations_name = false
-      RUBY
-
-      app "development"
-
-      assert_equal false, ActiveRecord.allow_deprecated_singular_associations_name
-    end
-
     test "ActiveRecord::Base.run_commit_callbacks_on_first_saved_instances_in_transaction is false by default for new apps" do
       app "development"