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Python Python Testing Be Assertive assertIn

can't solve this problem

Please assist

tests.py
import unittest

from string_fun import get_anagrams


class AnagramTestCase(unittest.TestCase):
    def test_empty_string(self):
        with self.assertRaises(ValueError):
          get_anagrams('')
string_fun.py
import itertools


def is_palindrome(yarn):
    """Return whether or not a string is a palindrome.

    A palindrome is a word/phrase that's the same in
    both directions.
    """
    return yarn == yarn[::-1]


def get_anagrams(*yarn):
    """Return a list of anagrams for a string."""
    # If only one letter came in, return it
    if yarn:
        if len(yarn[0]) <= 1:
            return list(yarn)
    else:
        raise ValueError("Must provide at least two letters")

    # Get all of the words from the dictionary
    words = set([
        w.strip().lower() for w in open('words.txt')
    ])

    output = set()
    for thread in yarn:
        thread = thread.lower()
        # Find all possible anagrams
        for i in range(2, len(thread)):
            fibers = set(
                [''.join(w) for w in itertools.permutations(thread, i)]
            )
            output.update(fibers.intersection(words))

    # Finally, return all of the combinations that are in the dictionary
    return sorted(list(output))
Chris Freeman
Chris Freeman
Treehouse Moderator 68,441 Points

Side issue for Kenneth Love: The embedded links in the code headers for tests.py and string_fun.py cannot differentiate between the two challenges: assertIn and assertRaises. both are using the <code>``tests.py</code> naming. This post is aboutassertRaisesbut the links redirect toassertIn`.

Chris Freeman
Chris Freeman
Treehouse Moderator 68,441 Points

sulaiman gannas: Your code appears to pass the first task in assertRaises. What is the question regarding the second task?

Challenge Task 2 of 2

Now add a new test, test_no_args that should also assertRaises(ValueError). This time, call get_anagrams() with no arguments.

Basically, you need to add a second function with this new name, change the arguments used when calling get_anagrams().

2 Answers

Jeffrey McGowan
Jeffrey McGowan
4,250 Points

the first task worked with:

class AnagramTestCase(unittest.TestCase):
    def test_empty_string(self):
        with self.assertRaises(ValueError):
          get_anagrams('')

while the second worked with:

class AnagramTestCase(unittest.TestCase):
    def test_empty_string(self):
        with self.assertRaises(ValueError):
          get_anagrams()

note that there's literally nothing in the parentheses there. i have the unfortunate habit of putting spaces ( ) in there which the grader didn't like : )

[MOD: added ```python markdown formatting -cf]

Chris Freeman
Chris Freeman
Treehouse Moderator 68,441 Points

Jeffrey, You are correct. I confirmed the assertRaises challenge will reject the second test if a space is between the parens in get_anagrams( ). This is in keeping with PEP8 coding guidelines, but perhaps is too harsh for the challenge. Tagging Kenneth Love for possible grader tweak to allow the whitespace.

Kenneth Love
Kenneth Love
Treehouse Guest Teacher

Updated the validator.

Like Chris said, it's a good idea to abide by PEP8.

Jeremy Fisk
Jeremy Fisk
7,768 Points

I had the same code for the first task except the last line I had double quotations for the empty string like this:

get_anagrams("")

and my code did not pass until I used single quotations., does anyone know why this happened?

Chris Freeman
Chris Freeman
Treehouse Moderator 68,441 Points

Code challenge graders get updated if issues have been found. This must have happen, I have verified that either single- or double-quotes will pass the first task.