To perform side-effect-free computations synchronously, Angular provides a testing utility known as _____.
- HttpClientTestingModule
- JasmineSpy
- MockAsyncService
- TestBed
To perform side-effect-free computations synchronously in Angular, you can use the TestBed utility for creating and configuring testing modules.
In an Angular application, you want to ensure that data for a specific route is fetched and ready before the route is activated. How would you achieve this?
- Configure route preloading strategies to ensure data is available before route activation.
- Fetch data in the route component's constructor and use a loading spinner until it's available.
- Implement a global data service to fetch data, and check data availability in the route's lifecycle hooks.
- Use route resolvers to fetch and resolve the data before activating the route.
To ensure that data for a specific route is fetched and ready before the route is activated, you should use route resolvers. Resolvers fetch and resolve the data before activating the route, ensuring the data is available when the route component is initialized.
In Angular, the replaceUrl property of the _____ object can be used to navigate while replacing the current URL in the browser's history.
- ActivatedRouteSnapshot
- NavigationExtras
- Router
- RouterStateSnapshot
In Angular, the replaceUrl property of the RouterStateSnapshot object can be used to navigate while replacing the current URL in the browser's history. It allows for URL manipulation.
When testing a directive that modifies the DOM, what should you consider to ensure that the tests are not flaky?
- Avoid testing such directives as they are inherently flaky
- Check for DOM changes in a loop until they are detected consistently
- Use a stubbed version of the directive to isolate DOM changes
- Use asynchronous timers to delay test execution until the DOM changes
To prevent flaky tests when testing a directive that modifies the DOM, use a stubbed version of the directive to isolate DOM changes and ensure reliable testing.
What does the async pipe do in an Angular template?
- Handles routing
- Renders HTML
- Subscribes to an Observable
- Transforms data
The async pipe in an Angular template subscribes to an Observable and automatically updates the view with the most recent data emitted by the Observable. It simplifies working with asynchronous data in templates.
Which lifecycle hook is best suited to react to changes in a component's input properties?
- ngAfterViewInit
- ngDoCheck
- ngOnChanges
- ngOnInit
The ngOnChanges lifecycle hook is best suited to react to changes in a component's input properties. It provides information about the changes to input properties.
When using Jasmine and Karma for testing, how can you ensure that a specific test or suite of tests is executed while others are ignored?
- Apply a custom test filter
- Enable verbose logging
- Set a test timeout
- Use the "xit" or "fdescribe" keywords
In Jasmine and Karma testing, you can ensure that a specific test or suite of tests is executed while others are ignored by using the "xit" (exclude it) or "fdescribe" (focus describe) keywords.
The _____ method in a Route Guard is used to check whether a user can navigate to a specific route.
- canActivate
- canDeactivate
- canNavigateTo
- checkRouteAccess
The canActivate method in a Route Guard is used to check whether a user can navigate to a specific route by returning true or false based on certain conditions.
What is the primary purpose of Dependency Injection (DI) in Angular?
- Define component behavior
- Enable two-way data binding
- Handle HTTP requests
- Manage external dependencies
The primary purpose of Dependency Injection (DI) in Angular is to manage external dependencies by providing them to a component when it's created.
What are the implications of importing a module that provides a service into multiple feature modules?
- Compilation error
- Multiple service instances
- No implications
- Shared singleton service instance
Importing a module with a service into multiple feature modules results in a shared singleton service instance, allowing data to be shared.