Coverage in CI pipelines in PyTest - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

Understanding coverage report output in pytest

What is the output of the following pytest coverage command snippet when run on a module with 3 functions, where 2 functions are tested and 1 is not?

PyTest

pytest --cov=my_module --cov-report=term

# Assume my_module has 3 functions: func_a, func_b, func_c
# Tests cover func_a and func_b only

A Coverage: 0% of statements executed

B Coverage: 66% of statements executed

C Coverage: 100% of statements executed

D Coverage: 33% of statements executed

💡 Hint

Think about how coverage percentage is calculated based on tested functions.

Since 2 out of 3 functions are tested, coverage is approximately 66%.

❓ assertion

intermediate

Correct assertion for coverage threshold in pytest

Which assertion correctly fails the test if coverage is below 80% in a pytest coverage report?

PyTest

coverage_percent = 75  # example value from coverage report

# Choose the correct assertion

A assert coverage_percent >= 80, f"Coverage too low: {coverage_percent}%"

B assert coverage_percent <= 80, f"Coverage too low: {coverage_percent}%"

C assert coverage_percent > 80, f"Coverage too low: {coverage_percent}%"

D assert coverage_percent < 80, f"Coverage too low: {coverage_percent}%"

💡 Hint

Coverage should be at least 80%.

Assertion B correctly checks coverage is 80% or more, failing otherwise.

❓ locator

advanced

Best practice for locating coverage report file in CI

In a CI pipeline, where should the coverage report file be stored for best accessibility and integration?

A Inside the source code directory alongside the code files

B In a temporary system directory outside the project

C In a dedicated reports directory at the root of the project

D In the user's home directory on the CI server

💡 Hint

Think about organization and ease of access for CI tools.

Storing reports in a dedicated directory at the project root keeps files organized and accessible.

❓ framework

advanced

Integrating coverage checks in pytest CI pipeline

Which pytest command line option combination ensures tests fail if coverage is below 90% during CI runs?

A pytest --cov=my_module --coverage-fail=90

B pytest --cov=my_module --fail-under=90

C pytest --coverage=my_module --fail-under=90

D pytest --cov=my_module --cov-fail-under=90

💡 Hint

Look for the correct pytest coverage fail threshold option.

The option --cov-fail-under=90 makes pytest fail if coverage is below 90%.

🔧 Debug

expert

Debugging missing coverage data in CI pipeline

In a CI pipeline, coverage reports show 0% coverage despite tests running successfully. What is the most likely cause?

A Coverage data file is overwritten before report generation

B Tests are not importing the module under test

C Coverage tool is not installed in the CI environment

D Coverage measurement started after tests finished running

💡 Hint

Think about how coverage data files are handled in CI.

If coverage data files are overwritten or deleted before report generation, coverage shows 0%.