Hm. I don’t know which one is specifically aimed at parsing files. But here are some tips:
Ruby Kickstart is a project I'm currently working on to teach Ruby. One aspect is the series of problems associated with test suites to verify that you did them correctly. You can download the code and try your hand at them. Once you have the code, run rake 1:1 to run the test for session1, problem1.
Ruby Koans is a series of tests that aims to learn how Ruby works. I really enjoyed going through this stuff. There is some kind of Zen that you fall into, almost the rhythm of solving and running tests (if you already know Ruby).
Meta Koans is also a series of tests proposed by Ruby Quiz , the purpose of which is to use metaprogramming to write code like attr_accessor. I found this unexpectedly complicated.
Puzzle Node is a project from Ruby Mendicant University to challenge people. I tried several problems and did not feel that they were very ruby, they seemed to me more generalized in nature. The input formats made me suggest that they were taken from other sources.
Ruby Warrior is an AI programming challenge from Ryan Bates ( Railscasts ). This is much more abstract than other things here, you can think of it as "write a robot that can move through mazes and fight / run away from opponents." Unfortunately, he doesn’t look like he did much with him, since he wrote it, so IDK if he is still good.
In addition, I find it erroneous to classify this as a “file parsing programming call”. The fact that input (a sequence of characters) happens to be given in a file does not create problems with reading / analyzing files. This is actually an algorithmic problem.
In addition, you can solve these problems in any language, including Ruby, which I made and which can be seen here .