Single assertion per test debate in JUnit - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the main idea behind the 'single assertion per test' approach?

It means each test method should check only one condition or behavior to keep tests simple and focused.

intermediate

Why might some developers prefer multiple assertions in one test?

Because it can reduce the number of test methods and group related checks, making tests shorter.

beginner

What is a downside of having multiple assertions in a single test?

If one assertion fails, the rest are skipped, so you might miss other problems in the same test run.

beginner

How does the single assertion rule help with debugging test failures?

It makes it clear exactly what failed, so you can fix problems faster without guessing which check caused the failure.

intermediate

Can you combine multiple related checks in one test without violating the single assertion idea?

Yes, by using one assertion that checks a combined condition or by splitting tests logically to keep clarity.

What is a key benefit of using a single assertion per test?

A Easier to identify which check failed

B Fewer test methods to write

C Runs tests faster

D Allows ignoring failures

Using one assertion per test helps quickly find the exact failure cause.

What happens if a test with multiple assertions fails on the first assertion?

A Remaining assertions are skipped

B All assertions run anyway

C Test automatically retries

D Test passes

JUnit stops running the test after the first failed assertion.

Which is a reason to use multiple assertions in one test?

A To avoid writing any assertions

B To group related checks together

C To make debugging harder

D To slow down test execution

Grouping related checks can make tests shorter and organized.

How can you keep tests clear while testing multiple conditions?

A Write tests without names

B Put all assertions in one big test

C Avoid assertions completely

D Use one assertion per test method

One assertion per test keeps tests focused and easy to understand.

What is a practical compromise in the single assertion debate?

A Write one test for the whole app

B Never write assertions

C Use one assertion per test only for unrelated checks

D Ignore test failures

You can group related checks but keep unrelated ones separate for clarity.

Explain the pros and cons of using a single assertion per test in JUnit.

Think about test clarity and failure detection.

Describe how you would decide when to use single or multiple assertions in a test.

Focus on clarity and maintenance.