`rewhere` allow to overwrite non-attribute nodes

Follow up to #39415.

activerecord/lib/active_record/relation/query_methods.rb

@@ -1399,7 +1399,7 @@ def order_column(field)
       def resolve_arel_attributes(attrs)
         attrs.flat_map do |attr|
           case attr
-          when Arel::Attributes::Attribute
+          when Arel::Predications
             attr
           when Hash
             attr.flat_map do |table, columns|

activerecord/lib/active_record/relation/where_clause.rb

@@ -104,7 +104,7 @@ def extract_attributes
         attrs = []
         predicates.each do |node|
           Arel.fetch_attribute(node) { |attr| attrs << attr } || begin
-            attrs << node.left if node.equality? && node.left.is_a?(Arel::Nodes::Node)
+            attrs << node.left if node.equality? && node.left.is_a?(Arel::Predications)
           end
         end
         attrs
@@ -157,18 +157,14 @@ def invert_predicate(node)
         end
 
         def except_predicates(columns)
-          non_attrs = columns.extract! { |node| node.is_a?(Arel::Nodes::Node) }
+          attrs = columns.extract! { |node| node.is_a?(Arel::Attribute) }
+          non_attrs = columns.extract! { |node| node.is_a?(Arel::Predications) }
+
           predicates.reject do |node|
-            if !non_attrs.empty? && node.equality? && node.left.is_a?(Arel::Nodes::Node)
+            if !non_attrs.empty? && node.equality? && node.left.is_a?(Arel::Predications)
               non_attrs.include?(node.left)
             end || Arel.fetch_attribute(node) do |attr|
-              columns.any? do |column|
-                if column.is_a?(Arel::Attributes::Attribute)
-                  attr == column
-                else
-                  attr.name.to_s == column.to_s
-                end
-              end
+              attrs.include?(attr) || columns.include?(attr.name.to_s)
             end
           end
         end

activerecord/test/cases/relation/merging_test.rb

@@ -137,6 +137,9 @@ def test_relation_merging_with_arel_equalities_keeps_last_equality
 
     devs = Developer.where(salary_attr.eq(80000)).merge(Developer.where(salary_attr.eq(9000)), rewhere: true)
     assert_equal [developers(:poor_jamis)], devs.to_a
+
+    devs = Developer.where(salary_attr.eq(80000)).rewhere(salary_attr.eq(9000))
+    assert_equal [developers(:poor_jamis)], devs.to_a
   end
 
   def test_relation_merging_with_arel_equalities_keeps_last_equality_with_non_attribute_left_hand
@@ -148,6 +151,9 @@ def test_relation_merging_with_arel_equalities_keeps_last_equality_with_non_attr
 
     devs = Developer.where(abs_salary.eq(80000)).merge(Developer.where(abs_salary.eq(9000)), rewhere: true)
     assert_equal [developers(:poor_jamis)], devs.to_a
+
+    devs = Developer.where(abs_salary.eq(80000)).rewhere(abs_salary.eq(9000))
+    assert_equal [developers(:poor_jamis)], devs.to_a
   end
 
   def test_relation_merging_with_eager_load