Is your feature request related to a problem? Please describe.
File routes.txt requires to check if route_long_name contains route_short_name.

However, depending on the number of characters of route_short_name, route_short_name could be contained in route_long_name.
For example: route_short_name is C, and route_long_name is Cxxxxxxxxxxx.
Here, route_short_name is just a character of the string defining route_long_name. Yet, with our current implementation, a notice would be generated although it should not.

Describe the solution you'd like
Implement a regex or an algorithm using a threshold to define whether route_long_name contains route_short_name.