Testing my twttr

In a file called twttr.py, reimplement Setting up my twttr from Problem Set 2, restructuring your code per the below, wherein shorten expects a str as input and returns that same str but with all vowels (A, E, I, O, and U) omitted, whether inputted in uppercase or lowercase.

def main():

def shorten(word):

if __name__ == "__main__":

Then, in a file called test_twttr.py, implement one or more functions that collectively test your implementation of shorten thoroughly, each of whose names should begin with test_ so that you can execute your tests with:

pytest test_twttr.py
  • Be sure to include
    import twttr


    from twttr import shorten

    atop test_twttr.py so that you can call shorten in your tests.

  • Take care to return, not print, a str in shorten. Only main should call print.

Before You Begin

Log into cs50.dev, click on your terminal window, and execute cd by itself. You should find that your terminal window’s prompt resembles the below:


Next execute

mkdir test_twttr

to make a folder called test_twttr in your codespace.

Then execute

cd test_twttr

to change directories into that folder. You should now see your terminal prompt as test_twttr/ $. You can now execute

code test_twttr.py

to make a file called test_twttr.py where you’ll write your tests.

How to Test

To test your tests, run pytest test_twttr.py. Be sure you have a copy of a twttr.py file in the same folder. Try to use correct and incorrect versions of twttr.py to determine how well your tests spot errors:

  • Ensure you have a correct version of twttr.py. Run your tests by executing pytest test_twttr.py. pytest should show that all of your tests have passed.
  • Modify the correct version of twttr.py in such a way as to create a bug. Your program might, for example, mistakenly only omit lowercase vowels! Run your tests by executing pytest test_twttr.py. pytest should show that at least one of your tests has failed.

You can execute the below to check your tests using check50, a program CS50 will use to test your code when you submit. (Now there are tests to test your tests!). Be sure to test your tests yourself and determine which tests are needed to ensure twttr.py is checked thoroughly.

check50 cs50/problems/2022/python/tests/twttr

Green smilies mean your program has passed a test! Red frownies will indicate your program output something unexpected. Visit the URL that check50 outputs to see the input check50 handed to your program, what output it expected, and what output your program actually gave.

How to Submit

In your terminal, execute the below to submit your work.

submit50 cs50/problems/2022/python/tests/twttr