PCPP2 Software Testing — 10 Questions

Question 1

Which of these is NOT a naming convention for discovery in pytest?

Accepted Answer

suite_*.py. Files starting with 'test_' or ending with '_test.py' are discovered. 'spec_test.py' would be discovered, but files like 'example.py' are ignored unless explicitly configured.

Answer

test_*.py

Answer

*_test.py

Answer

test_*.py

Question 2

In pytest, how can you skip a test based on the operating system platform?

Accepted Answer

@pytest.mark.skipif(sys.platform == 'win32'). The @pytest.mark.skipif decorator allows for conditional skipping based on expressions like sys.platform.

Answer

pytest.ignore_if(platform='win32')

Answer

pytest.skip_on('win32')

Answer

@pytest.skip(os='win32')

Question 3

Which 'unittest' assertion is best suited to verify that two floating-point numbers are equal within a certain tolerance?

Accepted Answer

assertAlmostEqual. assertAlmostEqual is specifically designed to handle floating-point precision issues by comparing values within a specified delta.

Answer

assertGreater

Answer

assertEqual

Answer

assertSequenceEqual

Question 4

You need to mock an object that is imported into a module. Which patch strategy correctly replaces the object where it is used?

Accepted Answer

Patch the object at the import location within the module being tested.. You must patch the object in the namespace where it is imported (the destination), not where it is defined, to ensure the replacement takes effect.

Answer

Use a global variable to override the module import.

Answer

Patch the object at its definition location.

Answer

Modify sys.modules directly.

Question 5

When using the 'unittest' framework, which method is executed exactly once before any test methods in a class are run?

Accepted Answer

setUpClass. The 'setUpClass' method is a class method that runs once before all tests in the class, whereas 'setUp' runs before each individual test.

Answer

setUp

Answer

pre_test

Answer

init

Question 6

In 'unittest.mock', when you want to return a specific value based on the input arguments of a mocked function, which property should be configured?

Accepted Answer

side_effect. The 'side_effect' property allows you to assign a function that computes the return value dynamically based on arguments, unlike 'return_value' which is static.

Answer

call_args

Answer

return_value

Answer

configure_mock

Question 7

You are refactoring a legacy module and want to use 'pytest' to check if a function raises a specific custom exception. Which construct is most idiomatic?

Accepted Answer

with pytest.raises(CustomError):. The 'pytest.raises' context manager is the standard way to verify that a block of code raises a specific exception type.

Answer

pytest.catch(CustomError)

Answer

assert func() == CustomError

Answer

with pytest.assert_raises(CustomError):

Question 8

You are writing a pytest fixture that opens a database connection. Which scope should you use to ensure the connection is created once per module, rather than once per test function?

Accepted Answer

scope='module'. The 'scope' argument in the @pytest.fixture decorator controls the lifetime. 'module' scope runs the fixture once per module.

Answer

scope='class'

Answer

scope='function'

Answer

scope='session'

Question 9

When using 'unittest.mock.MagicMock', what happens when you access an attribute that hasn't been defined?

Accepted Answer

It returns a new MagicMock instance.. MagicMock instances automatically create new MagicMock objects when you access previously undefined attributes.

Answer

It returns None.

Answer

It returns the string 'undefined'.

Answer

It raises an AttributeError.

Question 10

What command-line flag is used in pytest to stop the test suite execution after the first failure?

Accepted Answer

-x. The -x (or --exitfirst) flag causes pytest to exit immediately upon the first failed test.

Answer

--stop

Answer

-f

Answer

--halt