users: refactor bit_prefs search.

app/logical/approver_pruner.rb

@@ -5,7 +5,7 @@ module ApproverPruner
   MINIMUM_APPROVALS = 30
 
   def inactive_approvers
-    approvers = User.where("bit_prefs & ? > 0", User.flag_value_for("can_approve_posts"))
+    approvers = User.bit_prefs_match(:can_approve_posts, true)
     approvers = approvers.where("level < ?", User::Levels::MODERATOR)
 
     recently_promoted_approvers = UserFeedback.where("created_at >= ?", APPROVAL_PERIOD.ago).where_like(:body, "*You gained the ability to approve posts*").select(:user_id)

app/logical/danbooru/has_bit_flags.rb

@@ -5,18 +5,10 @@ module Danbooru
     module ClassMethods
       # NOTE: the ordering of attributes has to be fixed#
       # new attributes should be appended to the end.
-      def has_bit_flags(attributes, options = {})
-        field = options[:field] || :bit_flags
-
+      def has_bit_flags(attributes, field: :bit_flags)
         attributes.each.with_index do |attribute, i|
           bit_flag = 1 << i
 
-          define_singleton_method("flag_value_for") do |key|
-            index = attributes.index(key)
-            raise IndexError if index.nil?
-            1 << index
-          end
-
           define_method(attribute) do
             send(field) & bit_flag > 0
           end
@@ -33,6 +25,15 @@ module Danbooru
             end
           end
         end
+
+        # bit_prefs_match
+        define_singleton_method("#{field}_match") do |flag, value|
+          value = value ? 1 : 0
+          bits = attributes.length
+          bit_index = bits - attributes.index(flag.to_s) - 1
+
+          where(sanitize_sql(["get_bit(bit_prefs::bit(?), ?) = ?", bits, bit_index, value]))
+        end
       end
     end
   end