Within an @NgModule it's common to include in the imports a call to
a ModuleWithProviders function, for example RouterModule.forRoot().
The old ngc compiler was able to handle this pattern because it had
global knowledge of metadata of not only the input compilation unit
but also all dependencies.
The ngtsc compiler for Ivy doesn't have this knowledge, so the
pattern of ModuleWithProviders functions is more difficult. ngtsc
must be able to determine which module is imported via the function
in order to expand the selector scope and properly tree-shake
directives and pipes.
This commit implements a solution to this problem, by adding a type
parameter to ModuleWithProviders through which the actual module
type can be passed between compilation units.
The provider side isn't a problem because the imports are always
copied directly to the ngInjectorDef.
PR Close#24862
Rename @Injectable({scope -> providedIn}).
Instead of {providedIn: APP_ROOT_SCOPE}, accept {providedIn: 'root'}.
Also, {providedIn: null} implies the injectable should not be added
to any scope.
PR Close#22655
@Injectable() supports a scope parameter which specifies the target module.
However, it's still difficult to specify that a particular service belongs
in the root injector. A developer attempting to ensure that must either
also provide a module intended for placement in the root injector or target
a module known to already be in the root injector (e.g. BrowserModule).
Both of these strategies are cumbersome and brittle.
Instead, this commit adds a token APP_ROOT_SCOPE which provides a
straightforward way of targeting the root injector directly, without
requiring special knowledge of modules within it.
PR Close#22185
This change allows ReflectiveInjector to be tree shaken resulting
in not needed Reflect polyfil and smaller bundles.
Code savings for HelloWorld using Closure:
Reflective: bundle.js: 105,864(34,190 gzip)
Static: bundle.js: 154,889(33,555 gzip)
645( 2%)
BREAKING CHANGE:
`platformXXXX()` no longer accepts providers which depend on reflection.
Specifically the method signature when from `Provider[]` to
`StaticProvider[]`.
Example:
Before:
```
[
MyClass,
{provide: ClassA, useClass: SubClassA}
]
```
After:
```
[
{provide: MyClass, deps: [Dep1,...]},
{provide: ClassA, useClass: SubClassA, deps: [Dep1,...]}
]
```
NOTE: This only applies to platform creation and providers for the JIT
compiler. It does not apply to `@Compotent` or `@NgModule` provides
declarations.
Benchpress note: Previously Benchpress also supported reflective
provides, which now require static providers.
DEPRECATION:
- `ReflectiveInjector` is now deprecated as it will be remove. Use
`Injector.create` as a replacement.
closes#18496
