@pytest.fixture decorator - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

Output of a test using a simple fixture

What is the output when running this pytest test with the given fixture?

PyTest

import pytest

@pytest.fixture
def sample_data():
    return [1, 2, 3]

def test_sum(sample_data):
    assert sum(sample_data) == 6
    print("Test passed")

A Test passed\nFAILED

B SyntaxError

C Test passed\nPASSED

D FAILED

💡 Hint

Look at what the fixture returns and what the test asserts.

The fixture returns a list [1, 2, 3]. The test asserts that the sum is 6, which is true, so the test passes and prints 'Test passed'.

❓ assertion

intermediate

Correct assertion with fixture data

Given this fixture, which assertion correctly verifies the fixture data?

PyTest

import pytest

@pytest.fixture
def user_info():
    return {"name": "Alice", "age": 30}

A assert user_info["age"] == "30"

B assert user_info.name == "Alice"

C assert user_info.get("age") == 25

D assert user_info["name"] == "Alice"

💡 Hint

Remember how to access dictionary values in Python.

user_info is a dictionary. Accessing with user_info["name"] is correct. Option D fails because dicts don't have attribute access. Option D asserts wrong age. Option D compares int to string.

🔧 Debug

advanced

Identify the error in fixture usage

What error occurs when running this test code?

PyTest

import pytest

@pytest.fixture
def data():
    return [1, 2, 3]

def test_data():
    assert sum(data) == 6

A AssertionError

B TypeError: 'function' object is not iterable

C NameError: name 'data' is not defined

D No error, test passes

💡 Hint

Check how the fixture is used inside the test function.

The test function does not accept the fixture as a parameter, so 'data' refers to the fixture function itself, not its returned value. sum(data) tries to sum a function, causing TypeError.

🧠 Conceptual

advanced

Scope of pytest fixtures

Which fixture scope causes the fixture to be created once per test session?

A session

B class

C function

D module

💡 Hint

Think about how long the fixture lives during test runs.

The 'session' scope creates the fixture once for the entire test session. 'function' is per test function, 'class' per test class, 'module' per test module.

❓ framework

expert

Using autouse fixtures in pytest

What is the effect of setting autouse=True in a pytest fixture?

A The fixture runs automatically for all tests without needing to be requested

B The fixture runs only once per test class

C The fixture is skipped during test runs

D The fixture runs only when explicitly requested by test functions

💡 Hint

Consider how autouse changes fixture invocation.

Setting autouse=True makes the fixture run automatically for all tests in its scope, even if tests do not explicitly request it.