CSE 111: Programming with Functions

W03 Code-along Activity: Testing and Fixing Functions

Background

Most people around the world today have at least two names, a family name and a given name. In the United States, we usually write a person’s given name followed by his family name. However, when a computer lists names in alphabetical order, it is convenient to list the family name first and then the given name like this:

• Toussaint; Marie
• Toussaint; Olivier
• Washington; George
• Washington; Martha

When writing a program that alphabetizes names, it is often helpful to have the following three functions.

• make_full_name: Combines a person’s given name and family name into one string with the family name first.
• extract_family_name: Extracts a person’s family name from his full name.
• extract_given_name: Extracts a person’s given name from his full name.

A programmer has already written those three functions. However, there are mistakes in at least two of the three functions.

Program

Write three test functions named test_make_full_name, test_extract_family_name, and test_extract_given_name. Each of the test functions will test one of three previously written program functions. Use pytest to run the test functions and find and fix the mistakes, if any, that are in program functions.

Requirements

1. Write test_make_full_name so that it tests make_full_name with various names, including long names, short names, and hyphenated names. Fix the mistake in the make_full_name function.
2. Write test_extract_family_name so that it tests extract_family_name with various names, including long names, short names, and hyphenated names.
3. Write test_extract_given_name so that it tests extract_given_name with various names, including long names, short names, and hyphenated names. Fix the mistake in the extract_given_name function.

Enhancements

Here is a list of enhancements that you could make to the program. Your instructor will walk you through at least one of them. Feel free to complete others.

1. In the United States, mailing addresses are supposed to be written
   in this form: number street, city, state zipcode
   For example: 525 S Center St, Rexburg, ID 83460

   Download and save this Python file named address.py. Open a new Python file named test_address.py and write a test function named test_extract_city that verifies that the extract_city function works correctly.

2. Write a test function named test_extract_state that verifies that the extract_state function works correctly.
3. Write a test function named test_extract_zipcode that verifies that the extract_zipcode function works correctly.

Instructions

1. Create a folder for this week's code-along program.
2. Download the names.py python file and save it in your project folder you just created.
3. Open the folder you just created in VSCode.
4. Find the video that your instructor has posted for this assignment and code along with them to complete each of the requirements. Work through the requirements in order with the instructor rather than jumping ahead to more complicated steps to ensure you do not miss any concepts.

Additional Resources

You may use these additional resources for further study.

> python test_names.py
  ===================== test session starts ======================
  platform win32--Python 3.8.6, pytest-6.1.2, py-1.9.0, pluggy-0.1
  rootdir: C:\Users\cse111\week03
  collected 3 items
  test_names.py::test_make_full_name FAILED                 [ 33%]
  test_names.py::test_extract_family_name PASSED            [ 66%]
  test_names.py::test_extract_given_name FAILED             [100%]
  ========================== FAILURES ============================
  C:\Users\cse111\early-functions\docs\week03\teach_solution.py:
  AssertionError: assert 'Smith-Jones;Ava' == 'Smith-Jones; Ava'
  C:\Users\cse111\early-functions\docs\week03\names.py:31:
  ValueError: substring not found
  ================= 2 failed, 1 passed in 0.14s ==================

> python test_names.py
  ===================== test session starts ======================
  platform win32--Python 3.8.6, pytest-6.1.2, py-1.9.0, pluggy-0.1
  rootdir: C:\Users\cse111\week03
  collected 3 items
  test_names.py::test_make_full_name PASSED                 [ 33%]
  test_names.py::test_extract_family_name PASSED            [ 66%]
  test_names.py::test_extract_given_name PASSED             [100%]
  ====================== 3 passed in 0.12s =======================

Call Graph

The following call graph shows the function calls and returns in the sample solution for this assignment. From this call graph we see that the computer starts executing the sample test functions by calling the pytest.main function. While executing the pytest.main function, the computer calls the test_make_full_name function which calls the make_full_name function. Then while still executing pytest.main, the computer calls the test_extract_family_name function which calls the extract_family_name function. Then while still executing pytest.main, the computer calls the test_extract_given_name function which calls the extract_given_name function.

Submission

Please pause and re-watch any sections of the instructor video necessary until you have completed the entire activity and your program runs the same as the instructor's. When you are finished:

• Return to Canvas to take the quiz.

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