Issue #8342 has been updated by naruse (Yui NARUSE). Status changed from Rejected to Assigned leocassarani (Leo Cassarani) wrote: > Thanks naruse. However, this seems inconsistent with the way encodings are handled for individual IO instances. For example: > > io = File.open('hi', :encoding => "ascii-8bit:utf-16") > puts io.gets.encoding > # => UTF-16 > > This happens even if Encoding.default_external is set to ASCII-8BIT before opening the file. That side sounds buggy ---------------------------------------- Bug #8342: IO.readlines ignores Encoding.default_internal if Encoding.default_external is ASCII-8BIT https://bugs.ruby-lang.org/issues/8342#change-39089 Author: leocassarani (Leo Cassarani) Status: Assigned Priority: Normal Assignee: naruse (Yui NARUSE) Category: M17N Target version: current: 2.1.0 ruby -v: 1.9.3 Backport: 1.9.3: UNKNOWN, 2.0.0: UNKNOWN Under normal circumstances, IO.readlines will transcode from Encoding.default_external to Encoding.default_internal: File.open('hi', 'w') { |f| f.puts "hello\n" } Encoding.default_external = Encoding::US_ASCII Encoding.default_internal = Encoding::UTF_8 puts IO.readlines('hi').first.encoding #=> UTF-8 However, when Encoding.default_external is set to ASCII-8BIT, IO.readlines will always use ASCII-8BIT, regardless of what Encoding.default_internal is set to: File.open('hi', 'w') { |f| f.puts "hello\n" } Encoding.default_external = Encoding::ASCII_8BIT Encoding.default_internal = Encoding::UTF_8 puts IO.readlines('hi').first.encoding #=> ASCII-8BIT Using IO#gets instead of IO.readlines will produce the same behaviour. -- http://bugs.ruby-lang.org/