A test case is composed of 2 tests:

  • a test for the IDE
  • a test for validating a solution, often called a validator.

IDE tests are visible to the players whereas validators are hidden.


  • Test cases should cover all specifications

The more tests, the better.

  • Each validator must* differ from the corresponding test

It's only to ensure that the players don't hardcode the solution. * Sometimes, to cover edge cases, there is no other way than having the same test as validator

  • Each validator should check the same case as the corresponding test

They work by pairs.

  • The first test case must be a simple one

It's included in the statement as the example.

Best Practices

  • It can be useful to give explicit names to test cases to help players quickly understand their purpose
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