QUnit Testing Interview Questions & Answers

Question 1. What Is Qunit?

Answer :

QUnit is a unit testing framework for JavaScript programming language. It is important in the test driven development, and is used by jQuery, jQuery UI, and jQuery Mobile projects. QUnit is capable of testing any generic JavaScript codebase.

QUnit promotes the idea of "first testing then coding", which emphasizes on setting up the test data for a piece of code, which can be tested first and then implemented. This approach is like "test a little, code a little, test a little, code a little..." which increases the programmer’s productivity and the stability of program code reducing the programmer’s stress and the time spent on debugging.

Question 2. What Are The Features Of Qunit?

Answer :

Features of QUnit :

QUnit is an open source framework used for writing and running tests. Following are its most prominent features:

• QUnit provides Assertions for testing expected results.
• QUnit provides Test fixtures for running tests.
• QUnit tests allow to write code faster, which increases the quality.
• QUnit is elegantly simple. It is less complex and takes less time.
• QUnit tests can be run automatically and they check their own results and provide immediate feedback. There's no need to manually comb through a report of test results.
• QUnit tests can be organized into test suites containing test cases and even other test suites.
• QUnit shows test progress in a bar that is green if the test is going fine, and it turns red when a test fails.

Question 3. What Are The Ways To Use Qunit?

Answer :

There are two ways to use QUnit:

1. Local Installation : You can download QUnit library on your local machine and include it in your HTML code.
2. CDN Based Version : You can include QUnit library into your HTML code directly from Content Delivery Network (CDN).

Question 4. What Are The Important Apis Of Qunit?

Answer :

Some of the important Category of QUnit are:

• Assert: A set of assert methods.
• Async Control: For asynchronous operations.
• Callbacks: When integrating QUnit into other tools such as CI servers, these callbacks can be used as an API to read the test results.
• Configuration and Utilities: These methods and properties are used as utility helpers and to configure QUnit. For example, to adjust the runtime behavior directly, extend the QUnit API via custom assertions, etc.
• Test For testing operations.

Question 5. Specify Some Of The Assert Methods In Qunit?

Answer :

1. async() : Instruct QUnit to wait for an asynchronous operation.
2. deepEqual() : A deep recursive comparison, working on primitive types, arrays, objects, regular expressions, dates, and functions.
3. equal() : A non-strict comparison, roughly equivalent to JUnit's assertEquals.
4. expect() : Specify how many assertions are expected to run within a test.
5. notDeepEqual() : An inverted deep recursive comparison, working on primitive types, arrays, objects, regular expressions, dates, and functions.
6. notEqual() : A non-strict comparison, checking for inequality.
7. notOk() :A boolean check, inverse of ok() and CommonJS's assert.ok(), and equivalent to JUnit's assertFalse(). Passes if the first argument is false.
8. notPropEqual() : A strict comparison of an object's own properties, checking for inequality.
9. notStrictEqual() : A strict comparison, checking for inequality.
10. Ok() : A boolean check, equivalent to CommonJS's assert.ok() and JUnit's assertTrue(). Passes if the first argument is true.
11. propEqual() :A strict type and value comparison of an object's own properties.
12. push() : Report the result of a custom assertion.
13. strictEqual() : A strict type and value comparison.
14. throws() : Test if a callback throws an exception, and optionally compare the thrown error.

Question 6. Specify A Set Of Asynchronous Operations?

Answer :

1. async(): Instruct QUnit to wait for an asynchronous operation.
2. QUnit.asyncTest(): DEPRECATED: Add an asynchronous test to run. The test must include a call to QUnit.start().
3. QUnit.start(): PARTIALLY DEPRECATED: Start running the tests again after the testrunner was stopped. See QUnit.stop() and QUnit.config.autostart.
4. QUnit.stop(): DEPRECATED: Increase the number of QUnit.start() calls the testrunner should wait for before continuing.
5. QUnit.test(): Add a test to run.

Question 7. Which Browsers Support Qunit?

Answer :

QUnit supports the all browsers as jQuery 1.x supporting like IE6+ and Current - 1 for Chrome, Firefox, Safari and Opera.

Question 8. Why Does Sapui5 Use Qunit Tests?

Answer :

QUnit tests provide good support for asynchronous testing. These types of tests are often needed for UI functional tests, for example if you have to wait until rendering is done, animations are complete, or a backend call returns. In addition, a QUnit test page can be executed standalone in the browser without the need of an additional "tool". This makes the creation and execution of single QUnit tests much easier. Finally, QUnit is closely related to jQuery, which is also a fundamental part of SAPUI5.

Question 9. What Is Configuration Tools Of Qunit Test?

Answer :

• QUnit.assert: Namespace for QUnit assertions.
• QUnit.config: General configuration for QUnit. Check the description of each option for details
• QUnit.dump.parse: Advanced and extensible data dumping for JavaScript
• QUnit.extend: Copy the properties defined by the mixin object into the target object
• QUnit.push: DEPRECATED Report the result of a custom assertion
• QUnit.stack: Returns a single line string representing the stacktrace (call stack)

Question 10. What Is Async Control Of Q Unit Testing?

Answer :

• async: Instruct QUnit to wait for an asynchronous operation.
• start: QUnit.start() is used to start an async test set
• test: Add a test to run.
• timeout: Sets the length of time to wait for async operations before failing the test.

Question 11. What Is Callback Handlers Of Q Unit Testing?

Answer :

• QUnit.begin: Register a callback to fire whenever the test suite begins.
• QUnit.done: Register a callback to fire whenever the test suite ends.
• QUnit.log: Register a callback to fire whenever an assertion completes.
• QUnit.moduleDone: Register a callback to fire whenever a module ends.
• QUnit.moduleStart: Register a callback to fire whenever a module begins.
• QUnit.on: Register a callback to fire whenever the specified event is emitted.
• QUnit.testDone: Register a callback to fire whenever a test ends.
• QUnit.testStart: Register a callback to fire whenever a test begins.

Question 12. What Is Main Assertions Of Q Unit Testing?

Answer :

• module: Group related tests under a single label.
• only: Adds a test to exclusively run, preventing all other tests from running.
• skip: Adds a test like object to be skipped
• start: QUnit.start() is used to start an async test set
• test: Add a test to run.
• todo: Adds a test which expects at least one failing assertion during its run.