Miško Hevery d169c2434e feat(core): Add type information to injector.get() (#13785)
- Introduce `InjectionToken<T>` which is a parameterized and type-safe
  version of `OpaqueToken`.

DEPRECATION:
- `OpaqueToken` is now deprecated, use `InjectionToken<T>` instead.
- `Injector.get(token: any, notFoundValue?: any): any` is now deprecated
  use the same method which is now overloaded as
  `Injector.get<T>(token: Type<T>|InjectionToken<T>, notFoundValue?: T): T;`.

Migration
- Replace `OpaqueToken` with `InjectionToken<?>` and parameterize it.
- Migrate your code to only use `Type<?>` or `InjectionToken<?>` as
  injection tokens. Using other tokens will not be supported in the
  future.

BREAKING CHANGE:
- Because `injector.get()` is now parameterize it is possible that code
  which used to work no longer type checks. Example would be if one
  injects `Foo` but configures it as `{provide: Foo, useClass: MockFoo}`.
  The injection instance will be that of `MockFoo` but the type will be
  `Foo` instead of `any` as in the past. This means that it was possible
  to call a method on `MockFoo` in the past which now will fail type
  check. See this example:

```
class Foo {}
class MockFoo extends Foo {
  setupMock();
}

var PROVIDERS = [
  {provide: Foo, useClass: MockFoo}
];

...

function myTest(injector: Injector) {
  var foo = injector.get(Foo);
  // This line used to work since `foo` used to be `any` before this
  // change, it will now be `Foo`, and `Foo` does not have `setUpMock()`.
  // The fix is to downcast: `injector.get(Foo) as MockFoo`.
  foo.setUpMock();
}
```

PR Close #13785
2017-01-17 15:34:54 -06:00

81 lines
2.8 KiB
TypeScript

/**
* @license
* Copyright Google Inc. All Rights Reserved.
*
* Use of this source code is governed by an MIT-style license that can be
* found in the LICENSE file at https://angular.io/license
*/
import {InjectionToken, NgModule, destroyPlatform} from '@angular/core';
import {async} from '@angular/core/testing';
import {BrowserModule} from '@angular/platform-browser';
import {platformBrowserDynamic} from '@angular/platform-browser-dynamic';
import * as angular from '@angular/upgrade/src/angular_js';
import {UpgradeModule, downgradeInjectable} from '@angular/upgrade/static';
import {bootstrap, html} from '../test_helpers';
export function main() {
describe('injection', () => {
beforeEach(() => destroyPlatform());
afterEach(() => destroyPlatform());
it('should downgrade ng2 service to ng1', async(() => {
// Tokens used in ng2 to identify services
const Ng2Service = new InjectionToken('ng2-service');
// Sample ng1 NgModule for tests
@NgModule({
imports: [BrowserModule, UpgradeModule],
providers: [
{provide: Ng2Service, useValue: 'ng2 service value'},
]
})
class Ng2Module {
ngDoBootstrap() {}
}
// create the ng1 module that will import an ng2 service
const ng1Module =
angular.module('ng1Module', []).factory('ng2Service', downgradeInjectable(Ng2Service));
bootstrap(platformBrowserDynamic(), Ng2Module, html('<div>'), ng1Module)
.then((upgrade) => {
const ng1Injector = upgrade.$injector;
expect(ng1Injector.get('ng2Service')).toBe('ng2 service value');
});
}));
it('should upgrade ng1 service to ng2', async(() => {
// Tokens used in ng2 to identify services
const Ng1Service = new InjectionToken('ng1-service');
// Sample ng1 NgModule for tests
@NgModule({
imports: [BrowserModule, UpgradeModule],
providers: [
// the following line is the "upgrade" of an Angular 1 service
{
provide: Ng1Service,
useFactory: (i: angular.IInjectorService) => i.get('ng1Service'),
deps: ['$injector']
}
]
})
class Ng2Module {
ngDoBootstrap() {}
}
// create the ng1 module that will import an ng2 service
const ng1Module = angular.module('ng1Module', []).value('ng1Service', 'ng1 service value');
bootstrap(platformBrowserDynamic(), Ng2Module, html('<div>'), ng1Module)
.then((upgrade) => {
const ng2Injector = upgrade.injector;
expect(ng2Injector.get(Ng1Service)).toBe('ng1 service value');
});
}));
});
}