Write tests

[markusbaumeister]

There should be more tests to check the functionality. These should include some small examples as well as bigger ones that appear in practical calculations.

[sebasguts]

There is a difference between "tests" and "examples":

Tests should test the functionality of the package, and make sure it does not break with any updates on the code. This includes tests of corner cases that might not be of general interest.

Examples should illustrate the use of the package, and are best placed in the manual. In GAP, we usually test those, too, but examples have a different scope most of the time: Teaching people how to use this package.

Furthermore, tests should always be short and small, so one can run them without waiting too long. Examples can be longer.

Please be aware that tests should really test the interface, they should not test nauty.