`RouterTestingModule` is not needed as of v16. Instead, TestBed
automatically provides `MockPlatformLocation` in order to help test
navigations in the application. The location mocks in the
RouterTestingModule aren't necessary anymore.
There doesn't appear to be any real documentation around
`RouterTestingModule` other than the API docs.
PR Close#49427
Add a more specific error message when defining a lazy-loaded route using
`loadComponent` and passing it a NgModule instead of a standalone component,
when the user should actually be using `loadChildren`.
PR Close#49164
Due to being only 1 letter away from `provideRouter`, it is quite
possible that developers may accidentally use `provideRoutes` rather
than `provideRouter` in the `boostrapApplication` function. This change
will warn developers when `provideRoutes` is used without the `Router`.
PR Close#47896
When using `loadChildren` or `loadComponent`, a common pattern is to pass
a function that returns a `Promise` from a dynamic import:
```typescript
{
path: 'lazy',
loadComponent: () => import('./lazy-file').then(m => m.LazyCmp),
}
```
The `.then` part of the expression selects the particular exported
component symbol from the dynamically imported ES module.
ES modules can have a "default export", created with the `export default`
modifier:
```typescript
@Component({...})
export default class LazyCmp { ... }
```
This default export is made available to dynamic imports under the well-
known key of `'default'`, per the ES module spec:
https://tc39.es/ecma262/#table-export-forms-mapping-to-exportentry-records
This commit adds a feature to the router to automatically dereference such
default exports. With this logic, when `export default` is used, a `.then`
operation to select the particular exported symbol is no longer required:
```typescript
{
path: 'lazy',
loadComponent: () => import('./lazy-file'),
}
```
The above `loadComponent` operation will automatically use the `default`
export of the `lazy-file` ES module.
This functionality works for `loadChildren` as well.
PR Close#47586
Similarly to the symmetry being strengthened between children and loadChildren,
a new loadComponent property will be introduced as the asynchronous version of component.
This will allow for direct single-component lazy loading:
```
{path: 'lazy/a', loadComponent:
() => import('./lazy/a.component').then(m => m.ACmp)},
{path: 'lazy/b', loadComponent:
() => import('./lazy/b.component').then(m => m.BCmp)},
```
This option requires that the component being loaded is standalone and
is implemented as a runtime check.
Other notes:
* Components are not loaded until all guards and resolvers complete.
* Loading the component is included in the function passed to the router
preloading strategy
* `RouteConfigLoadStart` and `RouteConfigLoadEnd` events emit at the
start and end of the component loading
* `CanLoad` guards _do not_ apply to `loadComponent`. `canActivate`
should be used instead, just like you would do if it were simply
`component` instead.
PR Close#45705
This commit expands the `LoadChildrenCallback` to accept returning `Routes`
in addition to the existing `NgModule` type. In addition, it adds a
check to ensure these loaded routes all use standalone components.
The components must be standalone because if they were not,
we would not have the required `NgModule` which the component is declared in.
Existing API:
```
{path: 'lazy/route', loadChildren: import('./lazy').then(m => m.LazyModule)}
@NgModule({
imports: [
ExtraCmpModule,
RouterModule.forChild([
{path: 'extra/route', component: ExtraCmp},
]),
],
})
export class LazyModule {}
```
The new API for lazy loading route configs with standalone components
(no NgModule) is to expand `loadChildren` to allow returning simply a `Routes` array.
```
// parent.ts
{
path: 'parent',
loadChildren: () => import('./children').then(m => m.ROUTES),
}
// children.ts
export const ROUTES: Route[] = [
{path: 'child', component: ChildCmp},
];
```
Note that this includes minimal documentation updates. We need to
include a holistic update to the documentation for standalone components
in the future that includes this feature.
PR Close#45700
Currently, the only way to specify new providers for a `Route` and the
children is to create a new `NgModule` with those providers and use the
`loadChildren` feature. This is pretty confusing and a wholly indirect
way of accomplishing this task. With this commit, developers will be
able to specify a list of providers directly on the `Route` itself.
These providers will apply the that route and its children.
This feature was inspired by the upcoming standalone components feature.
This ties in there because, as mentioned before, the prior art for lazy
loading configs was to load an `NgModule`. This loaded module contained
new route configs _and_ could specify new providers. Separating those
two concepts, there should be a way to load _just_ some new routes, but
there should also be a way to specify new providers as well (something
you could do in the `NgModule` world and now will be able to do in the
world without any `NgModule` through this feature).
PR Close#45673
Andrew Scott