Jasmine JavaScript Testing Framework Jasmine Async Testing

Question 1

How does Jasmine signal that a test function is asynchronous using the callback pattern?

Accepted Answer

By accepting a done parameter in the test function

Answer

When it() or beforeEach() receives a function with a done parameter, Jasmine waits for done() to be called before proceeding.

Question 2

What happens if done() is never called in a Jasmine async test?

Accepted Answer

The test times out and is marked as failed

Answer

Jasmine has a configurable timeout interval, and any async test that doesn't call done within that window is failed.

Question 3

How do you handle async testing with Promises in Jasmine?

Accepted Answer

Return the Promise from the it() block

Answer

When it() returns a Promise, Jasmine awaits its resolution or rejection to determine pass or fail.

Question 4

What is the default async timeout interval in Jasmine?

Accepted Answer

5000 milliseconds

Answer

Jasmine's DEFAULT_TIMEOUT_INTERVAL defaults to 5000ms, after which async tests that haven't completed are failed.

Question 5

How do you globally change the async timeout for all Jasmine tests?

Accepted Answer

jasmine.DEFAULT_TIMEOUT_INTERVAL = newValue

Answer

Setting jasmine.DEFAULT_TIMEOUT_INTERVAL overrides the 5000ms default for all async specs in the suite.

Jasmine JavaScript Testing Framework Practice Test