@EnabledIfEnvironmentVariable in JUnit - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to enable the test only if the environment variable 'ENV' equals 'test'.

JUnit

@EnabledIfEnvironmentVariable(named = "ENV", matches = "[1]")
void testFeature() {
    // test code here
}

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

Aprod

Bstaging

Cdev

Dtest

Attempts:

3 left

💡 Hint

Common Mistakes

Using the wrong environment variable value in 'matches'.

Forgetting to use quotes around the match string.

The annotation @EnabledIfEnvironmentVariable activates the test only when the environment variable named 'ENV' matches the given value. Here, 'test' is the correct match.

2fill in blank

medium

Complete the code to enable the test only if the environment variable 'MODE' matches 'debug'.

JUnit

@EnabledIfEnvironmentVariable(named = "MODE", matches = "[1]")
void debugTest() {
    // debug test code
}

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

Adebug

Bproduction

Crelease

Dtest

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'Debug' instead of 'debug' (case mismatch).

Confusing 'MODE' with other environment variables.

The test runs only when the 'MODE' environment variable is set to 'debug'. This helps run debug-specific tests conditionally.

3fill in blank

hard

Fix the error in the annotation to enable the test only if the environment variable 'APP_ENV' equals 'production'.

JUnit

@EnabledIfEnvironmentVariable(named = "APP_ENV", matches = "[1]")
void productionTest() {
    // production test code
}

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

AProduction

Bprod

Cproduction

DPRODUCTION

Attempts:

3 left

💡 Hint

Common Mistakes

Using uppercase or capitalized strings that do not match the environment variable.

Using shorthand like 'prod' instead of full 'production'.

The environment variable value is case-sensitive. 'production' in lowercase matches the expected value exactly.

4fill in blank

hard

Fill both blanks to enable the test only if the environment variable 'TEST_ENV' matches 'qa' and the method name is 'qaTest'.

JUnit

@EnabledIfEnvironmentVariable(named = "[1]", matches = "[2]")
void qaTest() {
    // QA environment test
}

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

ATEST_ENV

Bqa

Cprod

Ddev

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping the environment variable name and value.

Using incorrect environment variable names.

The annotation checks that the environment variable named 'TEST_ENV' matches 'qa' to enable this test method.

5fill in blank

hard

Fill all three blanks to enable the test only if the environment variable 'BUILD_TYPE' matches 'nightly' and the method name is 'nightlyBuildTest'.

JUnit

@EnabledIfEnvironmentVariable(named = "[1]", matches = "[2]")
void [3]() {
    // Nightly build test
}

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

ABUILD_TYPE

Bnightly

CnightlyBuildTest

Drelease

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong environment variable names or values.

Mismatch between method name and the test purpose.

The test is enabled only when the 'BUILD_TYPE' environment variable equals 'nightly'. The method name must match 'nightlyBuildTest'.

Practice

1. What is the main purpose of the @EnabledIfEnvironmentVariable annotation in JUnit?

easy

A. To set environment variables before running tests

B. To disable all tests in a test class

C. To run a test only if a specific environment variable has a certain value

D. To run tests in parallel threads

Solution

1. Step 1: Understand the annotation's role

   <code>@EnabledIfEnvironmentVariable

2. Step 2: Identify its effect on tests

   It enables tests only when the environment variable matches the given value, skipping otherwise.

3. Final Answer:

   To run a test only if a specific environment variable has a certain value -> Option C

4. Quick Check:

   Runs test if env var matches = A [OK]

Hint: Think: runs test only if env var matches value [OK]

Common Mistakes:

• Confusing it with disabling tests
• Assuming it sets environment variables
• Thinking it controls test parallelism

2. Which of the following is the correct syntax to enable a test only when the environment variable ENV equals prod using @EnabledIfEnvironmentVariable?

easy

A. @EnabledIfEnvironmentVariable(named = "ENV", matches = "prod")

B. @EnabledIfEnvironmentVariable(name = "ENV", value = "prod")

C. @EnabledIfEnvironmentVariable(variable = "ENV", equals = "prod")

D. @EnabledIfEnvironmentVariable(env = "ENV", match = "prod")

Solution

1. Step 1: Recall correct attribute names

   The annotation uses named for the environment variable name and matches for the expected value.

2. Step 2: Match syntax with options

   @EnabledIfEnvironmentVariable(named = "ENV", matches = "prod") correctly uses named = "ENV" and matches = "prod".

3. Final Answer:

   @EnabledIfEnvironmentVariable(named = "ENV", matches = "prod") -> Option A

4. Quick Check:

   Correct attribute names = A [OK]

Hint: Remember: named and matches are correct attributes [OK]

Common Mistakes:

• Using incorrect attribute names like name or value
• Mixing attribute names with variable or env
• Using equals or match instead of matches

3. Given the following test code snippet, what will happen if the environment variable MODE is set to test?

@EnabledIfEnvironmentVariable(named = "MODE", matches = "prod")
void runOnlyInProd() {
    System.out.println("Running in prod mode");
}

medium

A. The test will be skipped and not run

B. The test will run and print "Running in prod mode"

C. The test will fail with an exception

D. The test will run but print nothing

Solution

1. Step 1: Check environment variable value

   The environment variable MODE is set to test, but the annotation requires prod.

2. Step 2: Understand annotation behavior

   Since the value does not match, the test is skipped and does not run.

3. Final Answer:

   The test will be skipped and not run -> Option A

4. Quick Check:

   Env var mismatch skips test = B [OK]

Hint: If env var value differs, test is skipped [OK]

Common Mistakes:

• Assuming test runs regardless of env var
• Expecting an exception on mismatch
• Thinking test runs but prints nothing

4. Identify the error in the following JUnit test code using @EnabledIfEnvironmentVariable:

@EnabledIfEnvironmentVariable(named = "APP_ENV", match = "dev")
void testInDev() {
    // test code
}

medium

A. The annotation must be placed on the class, not the method

B. The attribute name should be 'matches' instead of 'match'

C. The method must be static

D. The environment variable name cannot be 'APP_ENV'

Solution

1. Step 1: Check attribute names in annotation

   The correct attribute for matching value is matches, not match.

2. Step 2: Verify other code aspects

   Environment variable name can be any string, method need not be static, and annotation can be on method.

3. Final Answer:

   The attribute name should be 'matches' instead of 'match' -> Option B

4. Quick Check:

   Correct attribute is matches, not match [OK]

Hint: Use 'matches' attribute, not 'match' [OK]

Common Mistakes:

• Using 'match' instead of 'matches'
• Thinking method must be static
• Believing annotation only works on class

5. You want to run a test only if the environment variable DEPLOY_ENV is set to either staging or production. How can you achieve this using @EnabledIfEnvironmentVariable in JUnit?

hard

A. Use @EnabledIfEnvironmentVariable(named = "DEPLOY_ENV", matches = "staging,production") with comma-separated values

B. Use two test methods each annotated with @EnabledIfEnvironmentVariable(named = "DEPLOY_ENV", matches = "staging") and @EnabledIfEnvironmentVariable(named = "DEPLOY_ENV", matches = "production") respectively

C. Use @EnabledIfEnvironmentVariable(named = "DEPLOY_ENV", matches = "staging") and add an OR condition inside the test method

D. Use @EnabledIfEnvironmentVariable(named = "DEPLOY_ENV", matches = "staging|production") with regex matching

Solution

1. Step 1: Understand annotation supports regex

   The matches attribute supports regular expressions to match multiple values.

2. Step 2: Use regex for multiple values

   Using staging|production matches either value in one annotation.

3. Final Answer:

   Use @EnabledIfEnvironmentVariable(named = "DEPLOY_ENV", matches = "staging|production") with regex matching -> Option D

4. Quick Check:

   Regex in matches handles multiple values = B [OK]

Hint: Use regex in matches to cover multiple values [OK]

Common Mistakes:

• Trying to list multiple values with commas
• Splitting into multiple test methods unnecessarily
• Adding logic inside test instead of annotation