[ruby/reline] @convert_meta is true unless 8-bit characters

If Reline::IOGate.encoding contains 7-bit characters, convert-meta will set it On.

Because in readline(3):

>  The default is On, but readline will set it to Off if the locale contains eight-bit characters.

As far as I know, 7-bit encoding used in terminals is only US-ASCII.

https://github.com/ruby/reline/commit/b71d1fa496

1 files changed, 5 insertions, 0 deletions

diff --git a/lib/reline/config.rb b/lib/reline/config.rb
index 4b2655d8eb..5ef5ce4e8d 100644
--- a/lib/reline/config.rb
+++ b/lib/reline/config.rb
@@ -67,6 +67,7 @@ class Reline::Config
     @keyseq_timeout = 500
     @test_mode = false
     @autocompletion = false
+    @convert_meta = true if seven_bit_encoding?(Reline::IOGate.encoding)
   end
 
   def reset
@@ -387,4 +388,8 @@ class Reline::Config
     end
     ret
   end
+
+  private def seven_bit_encoding?(encoding)
+    encoding == Encoding::US_ASCII
+  end
 end