Returns `nil` when `AM::Errors#delete` doesn't delete anything:

- `AM::Errors#delete` currently returns an empty array when trying
  to delete an error that doesn't exist.

  This behaviour is surprising and I think it would be better
  to no return a truthy value but instead return nil like
  `Hash#delete` does.

1 files changed, 1 insertions, 1 deletions

diff --git a/activemodel/lib/active_model/errors.rb b/activemodel/lib/active_model/errors.rb
index f8ea21cf47..f6d6e64a25 100644
--- a/activemodel/lib/active_model/errors.rb
+++ b/activemodel/lib/active_model/errors.rb
@@ -199,7 +199,7 @@ module ActiveModel
       matches.each do |error|
         @errors.delete(error)
       end
-      matches.map(&:message)
+      matches.map(&:message).presence
     end
 
     # When passed a symbol or a name of a method, returns an array of errors