How do I parse a tab-delimited line that contains a quote? - ruby

Question

I'm using Ruby 2.4. How do I parse a tab-delimited line that contains a quote character? This is what's happening to me now ...
2.4.0 :003 > line = "11\tDave\tO\"malley"
=> "11\tDave\tO\"malley"
2.4.0 :004 > CSV.parse(line, col_sep: "\t")
CSV::MalformedCSVError: Illegal quoting in line 1.
from /Users/davea/.rvm/rubies/ruby-2.4.0/lib/ruby/2.4.0/csv.rb:1912:in `block (2 levels) in shift'
from /Users/davea/.rvm/rubies/ruby-2.4.0/lib/ruby/2.4.0/csv.rb:1868:in `each'
from /Users/davea/.rvm/rubies/ruby-2.4.0/lib/ruby/2.4.0/csv.rb:1868:in `block in shift'
from /Users/davea/.rvm/rubies/ruby-2.4.0/lib/ruby/2.4.0/csv.rb:1828:in `loop'
from /Users/davea/.rvm/rubies/ruby-2.4.0/lib/ruby/2.4.0/csv.rb:1828:in `shift'
from /Users/davea/.rvm/rubies/ruby-2.4.0/lib/ruby/2.4.0/csv.rb:1770:in `each'
from /Users/davea/.rvm/rubies/ruby-2.4.0/lib/ruby/2.4.0/csv.rb:1784:in `to_a'
from /Users/davea/.rvm/rubies/ruby-2.4.0/lib/ruby/2.4.0/csv.rb:1784:in `read'
from /Users/davea/.rvm/rubies/ruby-2.4.0/lib/ruby/2.4.0/csv.rb:1324:in `parse'
from (irb):4
from /Users/davea/.rvm/gems/ruby-2.4.0#global/gems/railties-5.0.1/lib/rails/commands/console.rb:65:in `start'
from /Users/davea/.rvm/gems/ruby-2.4.0#global/gems/railties-5.0.1/lib/rails/commands/console_helper.rb:9:in `start'
from /Users/davea/.rvm/gems/ruby-2.4.0#global/gems/railties-5.0.1/lib/rails/commands/commands_tasks.rb:78:in `console'
from /Users/davea/.rvm/gems/ruby-2.4.0#global/gems/railties-5.0.1/lib/rails/commands/commands_tasks.rb:49:in `run_command!'
from /Users/davea/.rvm/gems/ruby-2.4.0#global/gems/railties-5.0.1/lib/rails/commands.rb:18:in `<top (required)>'
from bin/rails:4:in `require'
from bin/rails:4:in `<main>'
Although teh example illustrates my point, I can't easily control the input coming in. So, although an answer coudl be< "Remove all quotes from teh string before parsing," I want to preserve the data as closely as possible.

Answer 1

That's a malformed document if you're trying to adhere to the CSV standard. Instad you might just brute-force it and pray there's no tabs in the data itself:
line.split(/\t/)
The CSV parsing library comes in handy when you're dealing with data like this:
"1\t2\t\"3a\t3b\"\t4"
Update: If you're prepared to abuse the CSV library a little then you can do this:
CSV.parse("11\tDave\tO\"malley", col_sep: "\t", quote_char: "\0")
That basically kills quote detection, so if there is other data that depends on that being processed correctly this may not work out.

Answer 2

"11\tDave\tO\"malley" is not valid CSV data. Strangely enough, the answer is to use two double-quotes, and to double quote each element
2.3.1 :001 > require 'csv'
=> true
2.3.1 :002 > line = "\"11\"\t\"Dave\"\t\"O\"\"malley\""
=> "\"11\"\t\"Dave\"\t\"O\"\"malley\""
2.3.1 :003 > puts line # for clarity
"11" "Dave" "O""malley"
=> nil
2.3.1 :004 > CSV.parse(line, col_sep: "\t")
=> [["11", "Dave", "O\"malley"]]