Merge branch 'master' into adequaterecord

* master: (28 commits)
  move AR length validation tests into separate test-case.
  No need for trailing slash on migration path.
  reset `@arel` when modifying a Relation in place.
  PostgreSQL Timestamps always map to `:datetime`.
  [ci skip] Improve formatting and yml
  Fix a typo in the doc of forty_two AR FinderMethod
  Improve readability of contributing to rails guide. [ci skip]
  Precompile the image we're referencing, too.
  `ActiveRecord::Base.no_touching` no longer triggers callbacks or start empty transactions.
  Fixed an issue with migrating legacy json cookies.
  Correct comment [ci skip]
  Perfer to define methods instead of calling test
  Fix syntax error
  Add CHANGELOG entry for #14757 [ci skip]
  Fix run-on sentences and improve grammar [skip ci]
  Add test for using ActionView::Helpers::FormHelper.label with block and html
  select! renamed to avoid name collision Array#select!
  Rearrange deck chairs on the titanic. Organize connection handling test cases.
  Change favicon_link_tag helper mimetype from image/vnd.microsoft.icon to image/x-icon.
  ActionController::Renderers documentation fix
  ...

3 files changed, 6 insertions, 4 deletions

diff --git a/activerecord/lib/active_record/associations/preloader/association.rb b/activerecord/lib/active_record/associations/preloader/association.rb
index 83c69586e6..bf461070e0 100644
--- a/activerecord/lib/active_record/associations/preloader/association.rb
+++ b/activerecord/lib/active_record/associations/preloader/association.rb
@@ -119,7 +119,7 @@ module ActiveRecord
           scope.references_values = Array(values[:references]) + Array(preload_values[:references])
           scope.bind_values       = (reflection_binds + preload_binds)
 
-          scope.select!   preload_values[:select] || values[:select] || table[Arel.star]
+          scope._select!   preload_values[:select] || values[:select] || table[Arel.star]
           scope.includes! preload_values[:includes] || values[:includes]
 
           if preload_values.key? :order
diff --git a/activerecord/lib/active_record/associations/preloader/through_association.rb b/activerecord/lib/active_record/associations/preloader/through_association.rb
index 70e97432e4..1fed7f74e7 100644
--- a/activerecord/lib/active_record/associations/preloader/through_association.rb
+++ b/activerecord/lib/active_record/associations/preloader/through_association.rb
@@ -84,7 +84,7 @@ module ActiveRecord
             end
 
             scope.references! reflection_scope.values[:references]
-            scope.order! reflection_scope.values[:order] if scope.eager_loading?
+            scope = scope.order reflection_scope.values[:order] if scope.eager_loading?
           end
 
           scope
diff --git a/activerecord/lib/active_record/associations/through_association.rb b/activerecord/lib/active_record/associations/through_association.rb
index ba7d2a3782..f8a85b8a6f 100644
--- a/activerecord/lib/active_record/associations/through_association.rb
+++ b/activerecord/lib/active_record/associations/through_association.rb
@@ -14,9 +14,11 @@ module ActiveRecord
         def target_scope
           scope = super
           chain.drop(1).each do |reflection|
+            relation = reflection.klass.all
+            relation.merge!(reflection.scope) if reflection.scope
+
             scope.merge!(
-              reflection.klass.all.
-                except(:select, :create_with, :includes, :preload, :joins, :eager_load)
+              relation.except(:select, :create_with, :includes, :preload, :joins, :eager_load)
             )
           end
           scope