Why assumptions control test execution in JUnit - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to skip the test if the assumption fails.

JUnit

import static org.junit.jupiter.api.Assumptions.*;

@Test
void testOnlyOnWindows() {
    assumeTrue(System.getProperty("os.name").startsWith([1]));
    // test code here
}

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

A"Mac"

B"Linux"

C"Windows"

D"Unix"

Attempts:

3 left

💡 Hint

Common Mistakes

Using the wrong OS name string causes the test to skip unexpectedly.

Not using quotes around the OS name string.

The assumption checks if the OS name starts with "Windows". If not, the test is skipped.

2fill in blank

medium

Complete the code to skip the test if the environment variable is not set to 'test'.

JUnit

import static org.junit.jupiter.api.Assumptions.*;

@Test
void testOnlyInTestEnv() {
    assumeTrue("test".equals(System.getenv([1])));
    // test code here
}

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

A"TEST_ENV"

B"ENVIRONMENT"

C"ENV"

D"APP_ENV"

Attempts:

3 left

💡 Hint

Common Mistakes

Using a wrong environment variable name causes the test to run or skip incorrectly.

Forgetting to use equals() for string comparison.

The assumption checks if the environment variable 'APP_ENV' equals 'test'. If not, the test is skipped.

3fill in blank

hard

Fix the error in the assumption to correctly skip the test when the condition is false.

JUnit

import static org.junit.jupiter.api.Assumptions.*;

@Test
void testSkipIfNotDebug() {
    assumeTrue(System.getProperty("debug") [1] "true");
    // test code here
}

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

A==

B.equals(

Cequals

D!=

Attempts:

3 left

💡 Hint

Common Mistakes

Using '==' for string comparison causes the assumption to fail unexpectedly.

Forgetting to close the equals method call with a parenthesis.

Use .equals("true") to compare strings correctly in Java. Using '==' compares references, not content.

4fill in blank

hard

Fill both blanks to assume the test runs only if the Java version is 17 or higher.

JUnit

import static org.junit.jupiter.api.Assumptions.*;

@Test
void testOnlyOnJava17OrHigher() {
    String version = System.getProperty("java.version");
    assumeTrue(Integer.parseInt(version.split("\\.")[[1]]) [2] 17);
    // test code here
}

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

A0

B1

C>=

D<

Attempts:

3 left

💡 Hint

Common Mistakes

Using index 1 instead of 0 causes wrong version parsing.

Using '<' instead of '>=' causes the test to skip incorrectly.

The first part of the version string is at index 0. We check if it is greater than or equal to 17 to run the test.

5fill in blank

hard

Fill all three blanks to assume the test runs only if the system property 'env' is 'dev' and the user is 'admin'.

JUnit

import static org.junit.jupiter.api.Assumptions.*;

@Test
void testOnlyForDevAdmin() {
    assumeTrue(System.getProperty([1]).equals([2]) && System.getProperty([3]).equals("admin"));
    // test code here
}

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

A"env"

B"dev"

C"user"

D"admin"

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up property names causes the assumption to fail.

Using incorrect string literals without quotes.

The assumption checks if the 'env' property equals 'dev' and the 'user' property equals 'admin'. If not, the test is skipped.