1 files changed, 47 insertions, 0 deletions
diff --git a/activerecord/lib/active_record/relation/predicate_builder/array_handler.rb b/activerecord/lib/active_record/relation/predicate_builder/array_handler.rb
new file mode 100644
index 0000000000..b8f3285c3e
--- /dev/null
+++ b/activerecord/lib/active_record/relation/predicate_builder/array_handler.rb
@@ -0,0 +1,47 @@
+require 'active_support/core_ext/string/filters'
+
+module ActiveRecord
+  class PredicateBuilder
+    class ArrayHandler # :nodoc:
+      def call(attribute, value)
+        values = value.map { |x| x.is_a?(Base) ? x.id : x }
+        nils, values = values.partition(&:nil?)
+
+        if values.any? { |val| val.is_a?(Array) }
+          ActiveSupport::Deprecation.warn(<<-MSG.squish)
+            Passing a nested array to Active Record finder methods is
+            deprecated and will be removed. Flatten your array before using
+            it for 'IN' conditions.
+          MSG
+
+          values = values.flatten
+        end
+
+        return attribute.in([]) if values.empty? && nils.empty?
+
+        ranges, values = values.partition { |v| v.is_a?(Range) }
+
+        values_predicate =
+          case values.length
+          when 0 then NullPredicate
+          when 1 then attribute.eq(values.first)
+          else attribute.in(values)
+          end
+
+        unless nils.empty?
+          values_predicate = values_predicate.or(attribute.eq(nil))
+        end
+
+        array_predicates = ranges.map { |range| attribute.between(range) }
+        array_predicates.unshift(values_predicate)
+        array_predicates.inject { |composite, predicate| composite.or(predicate) }
+      end
+
+      module NullPredicate
+        def self.or(other)
+          other
+        end
+      end
+    end
+  end
+end