Surprising behavior for character = true resp. character = :getc with stty

[stomar]

I am trying to get a single character from the user in a "cleaner" way than with SystemExtensions.get_character, which is not well documented and feels rather like a hack to me (see also issue #50).

While playing around with the echo and character settings, I stumbled over two issues(?):

1. The documentation is not very clear (at least to me) about the difference between character = true and character = :getc. When to choose which? Are they supposed to behave differently or is this only an implementation detail?
2. I do not understand the behavior of character = true in the example code below (newline and indentation; examples one and three behave as expected).

Output:

Your password?
password: 12345
Answer [ynaq]?
               key: q (character = true)
Answer [ynaq]? key: q (character = :getc)

Code:

require 'rubygems'
require 'highline/import'

answer = ask("Your password? ") do |q|
           q.echo = false
         end
puts "password: #{answer}"

key = ask("Answer [ynaq]? ") do |q|
        q.echo = false
        q.character = true
      end
puts "key: #{key} (character = true)"

key = ask("Answer [ynaq]? ") do |q|
        q.character = :getc
      end
puts "key: #{key} (character = :getc)"

[JEG2]

Can you share the output of the following?

$ ruby -r highline -ve 'p [HighLine::VERSION, HighLine::SystemExtensions::CHARACTER_MODE]'

[stomar]

ruby 1.9.3p194 (2012-04-20 revision 35410) [i686-linux]
["1.6.15", "stty"]

Same behavior with 1.9.3p327, 1.8.7p371 (using rvm) and system ruby (1.9.3p0)

[JEG2]

Thanks. I'll try to look into this when I get a chance.

[stomar]

Small update: I finally got termios installed (I used the wrong gem and gave up too early), and as you probably already know, with termios it works, the only difference between character = true and character = :getc is the newline in the former case, but there is no indentation.

[JEG2]

Yeah, termios is preferred. Still, stty should work better.

[alexch]

fyi I was having trouble with gem install termios and needed to do gem install ruby-termios instead... see this SO answer for more details

[carlosefonseca]

Hi! I'm hitting what I think is the same problem… with character = true, I get indentation on the next puts…

Code

require 'highline/import'

ask("question: ") { |q| q.character = true}
puts "text"

Output

❯ ./test.rb
question: y
           text

❯ ruby -r highline -ve 'p [HighLine::VERSION, HighLine::SystemExtensions::CHARACTER_MODE]'
ruby 2.0.0p481 (2014-05-08 revision 45883) [universal.x86_64-darwin14]
["1.7.2", "stty"]

I tried q.character = :getc but then I needed to add a newline the the next print… is there a way to work around this?

[abinoam]

A quick (and dirty) way to work around the issue is to prepend "\r" to the next string.

require 'highline/import'

ask("question: ") { |q| q.character = true }
puts "\rtext"

I'll be looking forward to fix it to the "reasonable expected behaviour". Thanks for reporting!

[abinoam]

@carlosefonseca I've just merged the workaround into 1-7-stable and into master Please tell me if it worked for you. When @JEG2 come back from vacation he'll make a gem release of them. But you are already able to install them manually if you like. I'll keep this issue open, as I'll review it later.

[carlosefonseca]

The test above now works with the manual installation of highline! Thanks!