A structural directive can specify a template guard for an input, such that
the type of that input's binding can be narrowed based on the guard's return
type. Previously, such template guards could only be methods, of which an
invocation would be inserted into the type-check block (TCB). For `NgIf`,
the template guard narrowed the type of its expression to be `NonNullable`
using the following declaration:
```typescript
export declare class NgIf {
static ngTemplateGuard_ngIf<E>(dir: NgIf, expr: E): expr is NonNullable<E>
}
```
This works fine for usages such as `*ngIf="person"` but starts to introduce
false-positives when e.g. an explicit non-null check like
`*ngIf="person !== null"` is used, as the method invocation in the TCB
would not have the desired effect of narrowing `person` to become
non-nullable:
```typescript
if (NgIf.ngTemplateGuard_ngIf(directive, ctx.person !== null)) {
// Usages of `ctx.person` within this block would
// not have been narrowed to be non-nullable.
}
```
This commit introduces a new strategy for template guards to allow for the
binding expression itself to be used as template guard in the TCB. Now,
the TCB generated for `*ngIf="person !== null"` would look as follows:
```typescript
if (ctx.person !== null) {
// This time `ctx.person` will successfully have
// been narrowed to be non-nullable.
}
```
This strategy can be activated by declaring the template guard as a
property declaration with `'binding'` as literal return type.
See #30235 for an example where this led to a false positive.
PR Close#30248
The LocationShim (replacement for `$location`) was added to centralize dealing with the browser URL. Additionally, an `onUrlChange` method was added to Angular's Location service. This PR adds a corresponding method to the LocationShim so updates from AngularJS can be tracked in Angular.
PR Close#30466
This commit provides a replacement for `$location`. The new service is written in Angular, and can be consumed into existing applications by using the downgraded version
of the provider.
Prior to this addition, applications upgrading from AngularJS to Angular could get into a situation where AngularJS wanted to control the URL, and would often parse or se
rialize the URL in a different way than Angular. Additionally, AngularJS was alerted to URL changes only through the `$digest` cycle. This provided a buggy feedback loop
from Angular to AngularJS.
With this new `LocationUpgradeProvider`, the `$location` methods and events are provided in Angular, and use Angular APIs to make updates to the URL. Additionally, change
s to the URL made by other parts of the Angular framework (such as the Router) will be listened for and will cause events to fire in AngularJS, but will no longer attempt
to update the URL (since it was already updated by the Angular framework).
This centralizes URL reads and writes to Angular and should help provide an easier path to upgrading AngularJS applications to Angular.
PR Close#30055
Without this change, the framework doesn't surface URL parts such as hostname, protocol, and port. This makes it difficult to rebuild a complete URL. This change provides new APIs to read these values.
PR Close#30055
Previously there wasn't a way to retrieve `history.state` from the `Location` service. The only time the framework exposed this value was in navigation events. This meant if you weren't using the Angular router, there wasn't a way to get access to this `history.state` value other than going directly to the DOM.
This PR adds an API to retrieve the value of `history.state`. This will be useful and needed to provide a backwards-compatible `Location` service that can emulate AngularJS's `$location` service since we will need to be able to read the state data in order to produce AngularJS location transition events.
This feature will additionally be useful to any application that wants to access state data through Angular rather than going directly to the DOM APIs.
PR Close#30055
Plural ICU expressions depend on the locale (different languages have different plural forms). Until now the locale was hard coded as `en-US`.
For compatibility reasons, if you use ivy with AOT and bootstrap your app with `bootstrapModule` then the `LOCALE_ID` token will be set automatically for ivy, which is then used to get the correct plural form.
If you use JIT, you need to define the `LOCALE_ID` provider on the module that you bootstrap.
For `TestBed` you can use either `configureTestingModule` or `overrideProvider` to define that provider.
If you don't use the compat mode and start your app with `renderComponent` you need to call `ɵsetLocaleId` manually to define the `LOCALE_ID` before bootstrap. We expect this to change once we start adding the new i18n APIs, so don't rely on this function (there's a reason why it's a private export).
PR Close#29249
Prior to this fix, both the `NgStyle` and `NgClass` directives made use
of `Renderer2` and this dependency raised issues for future versions of
Angular that cannot inject it. This patch ensures that there are two
versions of both directives: one for the VE and another for Ivy.
Jira Issue: FW-882
PR Close#28711
- Wraps the NgOnChangesFeature in a factory such that no side effects occur in the module root
- Adds comments to ngInherit property on feature definition interface to help guide others not to make the same mistake
- Updates compiler to generate the feature properly after the change to it being a factory
- Updates appropriate tests
PR Close#28187
This commit adds an ngTemplateGuard_ngIf static method to the NgIf
directive and an ngTemplateContextGuard static method to NgFor. The
function of these two static methods is to enable type narrowing
within generated type checking code for consumers of the directives.
PR Close#26203
`NgForOf` used to implement `OnChanges` and than use
`ngOnChanges` callback to detect when `ngForOf` binding
changed to update the differ. We now do the checking
manually which puts less pressure on the runtime to do
the bookkeeping and should result in minor perf improvement.
PR Close#23378
The utility functions `formatNumber`, `formatPercent`, `formatCurrency`, and `formatDate` used by the number, percent, currency and date pipes are now available for developers who want to use them outside of templates.
Fixes#20536
PR Close#22423
The AsyncPipe type signature was changed to allow
deferred creation of promises and observalbes that
is supported by the implementation by allowing
`Promise<T>|null|undefined` and by allowing
`Observable<T>|null|undefined`.
PR Close#22169
Currently, NavigationStart there is no way to know if an navigation was triggered imperatively or via the location change. These two use cases should be handled differently for a variety of use cases (e.g., scroll position restoration). This PR adds a navigation source field and restored navigation id (passed to navigations triggered by a URL change).
PR Close#21728
Currently, NavigationStart there is no way to know if an navigation was triggered imperatively or via the location change. These two use cases should be handled differently for a variety of use cases (e.g., scroll position restoration). This PR adds a navigation source field and restored navigation id (passed to navigations triggered by a URL change).
PR Close#21728
Allows a directive to use the expression passed directly to a property
as a guard instead of filtering the type through a type expression.
This more accurately matches the intent of the ngIf usage of its template
enabling better type inference.
Moved NgIf to using this type of guard instead of a function guard.
Closes: #20967
Structural directives can now specify a type guard that describes
what types can be inferred for an input expression inside the
directive's template.
NgIf was modified to declare an input guard on ngIf.
After this change, `fullTemplateTypeCheck` will infer that
usage of `ngIf` expression inside it's template is truthy.
For example, if a component has a property `person?: Person`
and a template of `<div *ngIf="person"> {{person.name}} </div>`
the compiler will no longer report that `person` might be null or
undefined.
The template compiler will generate code similar to,
```
if (NgIf.ngIfTypeGuard(instance.person)) {
instance.person.name
}
```
to validate the template's use of the interpolation expression.
Calling the type guard in this fashion allows TypeScript to infer
that `person` is non-null.
Fixes: #19756?
PR Close#20702
This is necessary to enable type-based optimizations with Closure.
Without explicity making these options the same named type, Closure
thinks they are different types and cannot disambiguate the `fromObject`
property.