Remove all references to `where_values` in association code

6 files changed, 14 insertions, 12 deletions

diff --git a/activerecord/lib/active_record/associations/association_scope.rb b/activerecord/lib/active_record/associations/association_scope.rb
index 3d71e73b3c..a2550fa382 100644
--- a/activerecord/lib/active_record/associations/association_scope.rb
+++ b/activerecord/lib/active_record/associations/association_scope.rb
@@ -167,8 +167,7 @@ module ActiveRecord
               scope.includes! item.includes_values
             end
 
-            scope.where_values += item.where_values
-            scope.bind_values  += item.bind_values
+            scope.where_clause += item.where_clause
             scope.order_values |= item.order_values
           end
 
diff --git a/activerecord/lib/active_record/associations/preloader.rb b/activerecord/lib/active_record/associations/preloader.rb
index 0a5ef601a2..c3e49007ea 100644
--- a/activerecord/lib/active_record/associations/preloader.rb
+++ b/activerecord/lib/active_record/associations/preloader.rb
@@ -89,7 +89,7 @@ module ActiveRecord
       #   { author: :avatar }
       #   [ :books, { author: :avatar } ]
 
-      NULL_RELATION = Struct.new(:values, :bind_values, :where_values).new({}, [], [])
+      NULL_RELATION = Struct.new(:values, :where_clause).new({}, Relation::WhereClause.empty)
 
       def preload(records, associations, preload_scope = nil)
         records       = Array.wrap(records).compact.uniq
diff --git a/activerecord/lib/active_record/associations/preloader/association.rb b/activerecord/lib/active_record/associations/preloader/association.rb
index 8f001770f7..23848f5e54 100644
--- a/activerecord/lib/active_record/associations/preloader/association.rb
+++ b/activerecord/lib/active_record/associations/preloader/association.rb
@@ -131,16 +131,13 @@ module ActiveRecord
         def build_scope
           scope = klass.unscoped
 
-          values         = reflection_scope.values
-          reflection_binds = reflection_scope.bind_values
+          values = reflection_scope.values
           preload_values = preload_scope.values
-          preload_binds  = preload_scope.bind_values
 
-          scope.where_values      = reflection_scope.where_values + preload_scope.where_values
+          scope.where_clause = reflection_scope.where_clause + preload_scope.where_clause
           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]
           scope.joins! preload_values[:joins] || values[:joins]
           scope.order! preload_values[:order] || values[:order]
diff --git a/activerecord/lib/active_record/associations/preloader/through_association.rb b/activerecord/lib/active_record/associations/preloader/through_association.rb
index 816a807f55..56aa23b173 100644
--- a/activerecord/lib/active_record/associations/preloader/through_association.rb
+++ b/activerecord/lib/active_record/associations/preloader/through_association.rb
@@ -78,10 +78,9 @@ module ActiveRecord
           if options[:source_type]
             scope.where! reflection.foreign_type => options[:source_type]
           else
-            unless reflection_scope.where_values.empty?
+            unless reflection_scope.where_clause.empty?
               scope.includes_values = Array(reflection_scope.values[:includes] || options[:source])
-              scope.where_values    = reflection_scope.where_values
-              scope.bind_values     = reflection_scope.bind_values
+              scope.where_clause = reflection_scope.where_clause
             end
 
             scope.references! reflection_scope.values[:references]
diff --git a/activerecord/lib/active_record/relation/where_clause.rb b/activerecord/lib/active_record/relation/where_clause.rb
index cd6da052a9..d1469d0a7a 100644
--- a/activerecord/lib/active_record/relation/where_clause.rb
+++ b/activerecord/lib/active_record/relation/where_clause.rb
@@ -3,6 +3,8 @@ module ActiveRecord
     class WhereClause # :nodoc:
       attr_reader :parts, :binds
 
+      delegate :empty?, to: :parts
+
       def initialize(parts, binds)
         @parts = parts
         @binds = binds
diff --git a/activerecord/test/cases/relation/where_clause_test.rb b/activerecord/test/cases/relation/where_clause_test.rb
index ec334240cc..b498739e84 100644
--- a/activerecord/test/cases/relation/where_clause_test.rb
+++ b/activerecord/test/cases/relation/where_clause_test.rb
@@ -66,6 +66,11 @@ class ActiveRecord::Relation
       # We might be able to change the implementation to remove conflicts by index, rather than column name
     end
 
+    test "a clause knows if it is empty" do
+      assert WhereClause.empty.empty?
+      assert_not WhereClause.new(["anything"], []).empty?
+    end
+
     private
 
     def table