From: matthew@... Date: 2017-05-19T22:32:28+00:00 Subject: [ruby-core:81295] [CommonRuby Feature#13585] select! and reject! do not returns the same array in specific situations Issue #13585 has been updated by phluid61 (Matthew Kerwin). It's pretty clearly documented: "If changes were made, it will return `self`, otherwise it returns `nil`." ---------------------------------------- Feature #13585: select! and reject! do not returns the same array in specific situations https://bugs.ruby-lang.org/issues/13585#change-64966 * Author: sobrinho (Gabriel Sobrinho) * Status: Open * Priority: Normal * Assignee: * Target version: ---------------------------------------- When all elements are returned on select!, the method returns nil. ~~~ (main) normal> [1,2,3].select! { |x| x == 0 } => [] (main) normal> [1,2,3].select! { |x| x == 1 } => [1] (main) normal> [1,2,3].select! { |x| x == 1 || x == 2 } => [1, 2] (main) normal> [1,2,3].select! { |x| x == 1 || x == 2 || x == 3 } => nil ``` When all elements are kept on reject!, nil is returned. ~~~ (main) normal> [1,2,3].reject! { |x| x == 0 } => nil (main) normal> [1,2,3].reject! { |x| x == 1 } => [2, 3] (main) normal> [1,2,3].reject! { |x| x == 1 || x == 2 } => [3] (main) normal> [1,2,3].reject! { |x| x == 1 || x == 2 || x == 3 } => [] ~~~ This is surprising since it breaks code in very specific situations that most people won't notice easily: ~~~ blocked_assets = relation.to_a.select! { |asset| asset.blocked? } unblocked_assets = relation.to_a.reject! { |asset| asset.unblocked? } ~~~ -- https://bugs.ruby-lang.org/ Unsubscribe: