Linux cat and less output for my text file is different from gedit and other gnome editor

I redirected ri’s ruby Array doc into a file but it didn’t look good in gedit. But text looks just fine in cli. That’s how my file looks in terminal editors. Everything is fine here.

= Array#to_param

(from gem activesupport-5.1.3)
------------------------------------------------------------------------------
  to_param()

------------------------------------------------------------------------------

Calls to_param on all its elements and joins the result with slashes. This is
used by url_for in Action Pack.


= Array#to_query

(from gem activesupport-5.1.3)
------------------------------------------------------------------------------
  to_query(key)

------------------------------------------------------------------------------

Converts an array into a string suitable for use as a URL query string, using
the given key as the param name.

  ['Rails', 'coding'].to_query('hobbies') # => "hobbies%5B%5D=Rails&hobbies%5B%5D=coding"


= Array#to_s

(from ruby core)
------------------------------------------------------------------------------
  to_s()

------------------------------------------------------------------------------


(from gem activesupport-5.1.3)
------------------------------------------------------------------------------
  to_s(format = :default)

------------------------------------------------------------------------------


= Array#to_sentence

(from gem activesupport-5.1.3)
------------------------------------------------------------------------------
  to_sentence(options = {})

------------------------------------------------------------------------------

But when I open it in gedit or other gnome editors, that’s how it looks like. Some specific words look in absurd format. Any suggestions or help will be appreciated.

= AArrrraayy##ttoo__ffoorrmmaatttteedd__ss

(from gem activesupport-5.1.3)
------------------------------------------------------------------------------
  to_formatted_s(format = :default)

------------------------------------------------------------------------------

Extends Array#to_s to convert a collection of elements into a comma separated
id list if :db argument is given as the format.

  Blog.all.to_formatted_s(:db)  # => "1,2,3"
  Blog.none.to_formatted_s(:db) # => "null"
  [1,2].to_formatted_s          # => "[1, 2]"


= AArrrraayy##ttoo__ppaarraamm

(from gem activesupport-5.1.3)
------------------------------------------------------------------------------
  to_param()

------------------------------------------------------------------------------

Calls to_param on all its elements and joins the result with slashes. This is
used by url_for in Action Pack.


= AArrrraayy##ttoo__qquueerryy

(from gem activesupport-5.1.3)
------------------------------------------------------------------------------
  to_query(key)

------------------------------------------------------------------------------

Converts an array into a string suitable for use as a URL query string, using
the given key as the param name.

  ['Rails', 'coding'].to_query('hobbies') # => "hobbies%5B%5D=Rails&hobbies%5B%5D=coding"


= AArrrraayy##ttoo__ss

(from ruby core)
------------------------------------------------------------------------------
  to_s()

------------------------------------------------------------------------------


(from gem activesupport-5.1.3)
------------------------------------------------------------------------------
  to_s(format = :default)

------------------------------------------------------------------------------


= AArrrraayy##ttoo__sseenntteennccee

(from gem activesupport-5.1.3)
------------------------------------------------------------------------------
  to_sentence(options = {})

------------------------------------------------------------------------------

I tried opening it into every system. but text is still messed up everywhere except terminal editors like cat or less. Does it have anything to do with text encoding?

Answer

ri outputs documentation formatted as ASCII text, with overstriking. You can check this by running the file command on your file.

Some parts of the documentation are bolded, which is represented by some character, backspace (^H) and the first character again. It seems that gedit and other gnome editors ignore these backspace characters, leaving the actual character repeated.

You can output just the ASCII like this: ri Array | col -bx > array.txt

An answer with more information about nroff formatting: https://unix.stackexchange.com/a/274795