re: Aleksei Matiushkin, Could you take a look at this? link. Ruby 2.5.1 CSV library is not properly parsing a csv(.txt) file when parsed with headers...
 

How the debugging of 3rd party library bugs within an explicit ruby version is any kind of CR? This is the perfect question for Stack Overflow and I am pretty sure there are many people ready to help you with this.

I don’t have ruby environment at all, but you might start with

- converter = lambda { |field, _| field.strip rescue field }
+ converter = lambda { |field, _| field.strip rescue field.to_s }

Rescuing to nil might cause issues, also I doubt I can understand why.

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