encoding_test.rb

Encoding.list.each do |encoding|
  print "Testing #{encoding.name}"
  
  (0..0xffff).each do |i|
    print "." if i % 256 == 0
    
    begin
      result = i.chr(encoding)
    rescue RangeError
      next
    rescue Exception => e
      puts "expected #{i}.chr(#{encoding.name.inspect}) to raise RangeError, but it raised #{e.inspect} instead"
      next
    end
    
    if result.length != 1
      puts "expected #{i}.chr(#{encoding.name.inspect}) to be a single character, but it was #{result.length}"
    elsif !result.valid_encoding?
      puts "expected #{i}.chr(#{encoding.name.inspect}) to return a validly encoded string, but it returned #{result.inspect} instead"
    elsif result.encoding != encoding
      puts "expected #{i}.chr(#{encoding.name.inspect}) to be encoded as #{encoding.name}"
    elsif result.codepoints.to_a != [i]
      puts "expected #{i}.chr(#{encoding.name.inspect}) to encode the codepoint #{i}, but it encoded #{result.codepoints.to_a} instead"
    end
  end
  
  print "\n"
end