pytest-timeout for time limits - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to set a timeout of 5 seconds for the test function.

PyTest

import pytest

@pytest.mark.timeout([1])
def test_example():
    assert 1 + 1 == 2

Drag options to blanks, or click blank then click option'

A10

BNone

C0

D5

Attempts:

3 left

💡 Hint

Common Mistakes

Using zero or None as timeout disables the timeout.

Forgetting to import pytest.

The @pytest.mark.timeout(5) decorator sets a 5-second timeout for the test.

2fill in blank

medium

Complete the code to apply a timeout of 3 seconds using a pytest fixture.

PyTest

import pytest

@pytest.fixture(autouse=True)
def set_timeout():
    pytest.timeout = [1]


def test_fast():
    assert True

Drag options to blanks, or click blank then click option'

A0

B10

C3

DNone

Attempts:

3 left

💡 Hint

Common Mistakes

Setting timeout to zero disables it.

Not using autouse=True to apply fixture automatically.

Setting pytest.timeout = 3 inside an autouse fixture applies a 3-second timeout to tests.

3fill in blank

hard

Fix the error in the code to correctly apply a 2-second timeout to the test.

PyTest

import pytest

@pytest.mark.timeout([1])
def test_slow():
    import time
    time.sleep(3)
    assert True

Drag options to blanks, or click blank then click option'

A2

B3

C0

D-1

Attempts:

3 left

💡 Hint

Common Mistakes

Setting timeout equal or greater than sleep time does not cause timeout.

Using negative timeout values.

The timeout must be less than the sleep time to trigger a timeout failure. Using 2 seconds works.

4fill in blank

hard

Fill both blanks to set a timeout of 4 seconds and handle the timeout exception in the test.

PyTest

import pytest
from pytest_timeout import TimeoutException

@pytest.mark.timeout([1])
def test_timeout_handling():
    try:
        import time
        time.sleep(5)
    except [2]:
        assert True

Drag options to blanks, or click blank then click option'

A4

BTimeoutError

CTimeoutException

DException

Attempts:

3 left

💡 Hint

Common Mistakes

Catching wrong exception type.

Setting timeout longer than sleep time.

Use @pytest.mark.timeout(4) to set timeout and catch TimeoutException to handle it.

5fill in blank

hard

Fill all three blanks to apply a 6-second timeout, skip the test if it times out, and import the correct decorator.

PyTest

import pytest
from pytest_timeout import [1]

@[2].timeout([3])
def test_skip_on_timeout():
    import time
    time.sleep(10)
    assert True

Drag options to blanks, or click blank then click option'

Amark

Btimeout

C6

DTimeoutException

Attempts:

3 left

💡 Hint

Common Mistakes

Importing wrong names from pytest_timeout.

Using incorrect decorator syntax.

Import mark from pytest_timeout and use @mark.timeout(6) to set a 6-second timeout.

Practice

1. What is the main purpose of using pytest-timeout in test cases?

easy

A. To stop tests that run longer than a specified time limit

B. To increase the speed of test execution by skipping tests

C. To automatically retry failed tests

D. To generate detailed test coverage reports

Solution

1. Step 1: Understand pytest-timeout functionality

   pytest-timeout is designed to stop tests that exceed a time limit to prevent long waits.

2. Step 2: Compare options with pytest-timeout purpose

   Only To stop tests that run longer than a specified time limit matches this purpose; others describe different pytest features.

3. Final Answer:

   To stop tests that run longer than a specified time limit -> Option A

4. Quick Check:

   pytest-timeout stops long tests = C [OK]

Hint: Remember: pytest-timeout stops tests running too long [OK]

Common Mistakes:

• Confusing timeout with test retries
• Thinking it speeds up tests by skipping
• Mixing it with coverage reporting

2. Which of the following is the correct way to set a 5-second timeout for a test function using pytest-timeout?

easy

A. @pytest.mark.timeout(seconds=5)
def test_example(): pass

B. @pytest.timeout(5)
def test_example(): pass

C. @pytest.mark.timeout(5)
def test_example(): pass

D. @pytest.timeout(seconds=5)
def test_example(): pass

Solution

1. Step 1: Recall correct pytest-timeout decorator syntax

   The correct decorator is @pytest.mark.timeout(5) using a positional argument.

2. Step 2: Check each option's syntax

   @pytest.mark.timeout(5) def test_example(): pass uses correct syntax with positional argument 5. @pytest.mark.timeout(seconds=5) def test_example(): pass incorrectly uses keyword argument 'seconds=5'. The options using @pytest.timeout use wrong decorator names.

3. Final Answer:

   @pytest.mark.timeout(5) def test_example(): pass -> Option C

4. Quick Check:

   Use @pytest.mark.timeout(5) = A [OK]

Hint: Use @pytest.mark.timeout(5) to set 5 seconds [OK]

Common Mistakes:

• Using @pytest.timeout instead of @pytest.mark.timeout
• Passing seconds as a keyword argument
• Missing the @pytest.mark prefix

3. Given the following test code, what will happen when running pytest?

@pytest.mark.timeout(2)
def test_sleep():
    import time
    time.sleep(3)

medium

A. The test will pass because sleep is allowed

B. The test will raise a syntax error

C. The test will be skipped automatically

D. The test will fail due to exceeding the 2-second timeout

Solution

1. Step 1: Analyze the timeout and sleep duration

   The test has a 2-second timeout but sleeps for 3 seconds, exceeding the limit.

2. Step 2: Understand pytest-timeout behavior on timeout

   pytest-timeout stops the test and marks it as failed if it runs longer than the timeout.

3. Final Answer:

   The test will fail due to exceeding the 2-second timeout -> Option D

4. Quick Check:

   Sleep 3s > timeout 2s = fail [OK]

Hint: If test runs longer than timeout, it fails [OK]

Common Mistakes:

• Assuming test passes despite timeout
• Thinking test is skipped automatically
• Confusing timeout with syntax errors

4. Identify the error in the following pytest test using pytest-timeout:

@pytest.mark.timeout(3)
def test_loop():
    for i in range(5):
        time.sleep(1)

medium

A. Timeout value is too low for the loop

B. Missing import of the time module

C. Incorrect decorator syntax

D. The test will pass without errors

Solution

1. Step 1: Check for missing imports

   The test uses time.sleep(1) but does not import the time module.

2. Step 2: Verify other aspects

   The timeout and decorator syntax are correct. The missing import will cause a NameError.

3. Final Answer:

   Missing import of the time module -> Option B

4. Quick Check:

   Using time.sleep without import = error [OK]

Hint: Always import modules before using their functions [OK]

Common Mistakes:

• Ignoring missing imports
• Assuming timeout causes error instead
• Thinking decorator syntax is wrong

5. You want to apply a 10-second timeout to all tests in a pytest file without adding @pytest.mark.timeout to each test. Which is the best way to do this?

hard

A. Add pytestmark = pytest.mark.timeout(10) at the top of the test file

B. Set timeout=10 in pytest.ini configuration file

C. Use @pytest.mark.timeout(10) on a dummy test and inherit it

D. Add timeout=10 as a command line argument every time

Solution

1. Step 1: Understand pytestmark usage

   Setting pytestmark = pytest.mark.timeout(10) applies the timeout decorator to all tests in the file automatically.

2. Step 2: Evaluate other options

   Adding timeout as a command line argument requires specifying --timeout=10 every time pytest is run; setting timeout in pytest.ini applies it globally to all tests in the project; using a dummy test for inheritance is not a valid pytest feature. pytestmark is best for this specific file.

3. Final Answer:

   Add pytestmark = pytest.mark.timeout(10) at the top of the test file -> Option A

4. Quick Check:

   pytestmark applies decorator to all tests [OK]

Hint: Use pytestmark variable to apply timeout to all tests [OK]

Common Mistakes:

• Trying to set timeout in pytest.ini (global, not file-specific)
• Using dummy test inheritance (not valid)
• Relying on command line timeout argument (inconvenient)