This commit updates TestBed logic to take into account situations when dependencies loaded within `@defer` blocks may import NgModules with providers. For such components, we invoke provider override function, which recursively inspects and applies the necessary changes.
PR Close#54667
In zone-full applications, this is already true because effects are
scheduled inside a microtask and tracked by ZoneJS. When not using
zones, this should stay consistent on principle and for testability
reasons. A general pattern with zoneless testing will be to update state
and `await` some promise (i.e. `fixture.whenStable`, which will be
linked to `ApplicationRef.isStable`).
PR Close#53835
The current behavior of `autoDetect` in `ComponentFixture` does not
match production very well. It has several flaws that make it an
insufficient change detection mechanism:
* It runs change detection for the component under test _after_ views
attached to the `ApplicationRef`. This can cause real behavior
differences that break in production, because tests can observe view
refreshes in the incorrect order (for example, a dialog refreshing
before the component which opened it).
* Because of the above ordering, render hooks registered during change
detection of the fixture views _will not execute at all_ because
`ApplicationRef.tick` already happen.
* It does not rerun change detection on the view tree if there are more
dirty views to refresh after the render hooks complete.
* It effectively hides/swallows errors from change detection inside the
`onMicrotaskEmpty` subscription by not reporting them to the error
handler. Instead, this error ends up being unhandled in the
subscription and rxjs throws these in a `setTimeout`.
All of the above are problematic but this commit _does not_ fix the
final point. Ideally, we can land this in a future change but this
requires additional internal fixes. In the meantime, we have to juggle
special-case handling of the component fixture views within
`ApplicationRef.tick` using some special events to retain current
behavior and avoid errors from the fixture propagating to the `ErrorHandler`.
breaking note for future when isG3 flag condition is removed for v18:
The `ComponentFixture.autoDetect` feature now executes
change detection for the fixture within `ApplicationRef.tick`. This more
closely matches the behavior of how a component would refresh in
production. The order of component refresh in tests may be slightly
affected as a result, especially when dealing with additional components
attached to the application, such as dialogs. Tests sensitive to this
type of change (such as screenshot tests) may need to be updated.
PR Close#54354
One downside of implicit dependency tracking in `effect()`s is that it's easy
to for downstream code to end up running inside the effect context by accident.
For example, if an effect raises an event (e.g. by `next()`ing a `Subject`), the
subscribers to that `Observable` will run inside the effect's reactive context,
and any signals read within the subscriber will end up as dependencies of the
effect. This is why the `untracked` function is useful, to run certain
operations without incidental signal reads ending up tracked.
However, knowing when this is necessary is non-trivial. For example, injecting
a dependency might cause it to be instantiated, which would run the constructor
in the effect context unless the injection operation is untracked.
Therefore, Angular will automatically drop the reactive context within a number
of framework APIs. This commit addresses these use cases:
* creating and destroying views
* creating and destroying DI injectors
* injecting dependencies
* emitting outputs
Fixes#54548
There are likely other APIs which would benefit from this approach, but this
is a start.
PR Close#54614
As a part of #54154, an old parser behavior came up where two-way bindings were parsed by appending `= $event` to the event side. This was problematic, because it allowed some non-writable expressions to be passed into two-way bindings.
These changes introduce a migration that will change the two-way bindings into two separate input/output bindings that represent the old behavior so that in a future version we can throw a parser error for the invalid expressions.
```ts
// Before
@Component({
template: `<input [(ngModel)]="a && b"/>`
})
export class MyComp {}
// After
@Component({
template: `<input [ngModel]="a && b" (ngModelChange)="a && (b = $event)"/>`
})
export class MyComp {}
```
PR Close#54630
Angular has the `@Attribute` decorator that allows for attributes to be injected from the host node, but we don't have an equivalent for the `inject` function. These changes introduce the new `HostAttributeToken` class that can be used to inject attributes similarly to `@Attribute`. It can be used as follows:
```typescript
import {HostAttributeToken, inject} from '@angular/core';
class MyDir {
someAttr = inject(new HostAttributeToken('some-attr'));
}
```
The new API works similarly to `@Attribute` with one key exception: it will throw a DI error when the attribute doesn't exist, instead of returning `null` like `@Attribute`. We made this change to align its behavior closer to other injection tokens.
PR Close#54604
This commit ensures that any internal render hooks that cause views to
become dirty again first refresh those dirty views before running user
render hooks. This ensures that user render hooks have the most complete
render state possible and stops them from needlessly executing multiple
times. This is important to maintain the goal of the public render
hooks, which is to provide the safest place to place code that depends
on DOM state, especially in ways that may force a browser paint.
PR Close#54224
This adds a helper function to defer application state updates to the
first possible "safe" moment. If application-wide change detection
(ApplicationRef.tick) is currently executing when this function is used,
the callback will execute as soon as all views attached to the
`ApplicationRef` have been refreshed. Refreshing the application views
will happen again before `checkNoChanges` executes.
When a change detection is _not_ running, this state update will execute
in the microtask queue.
This function is necessary as a replacement for current
`Promise.resolve().then(() => stateUpdate())` to be zoneless compatible
while ensuring those state updates are synchronized to the DOM before
the browser repaint. Without this, updates done in `Promise.resolve(...)` would
queue another round of change detection in zoneless applications, and
this change detection could happen in the next browser frame, and cause
noticeable flicker for the user.
Additionally, this function provides a way to perform state updates that
will run on the server as well as in the browser.
Last, current applications using `ngZone: 'noop'` may not be
calling `ApplicationRef.tick` at all so this function provides a
mechanism to ensure the state update still happens by racing
a microtask with `afterNextRender` (which might never execute).
PR Close#54224
Fixes that initializer functions weren't being recognized if they are aliased (e.g. `import {model as alias} from '@angular/core';`).
To do this efficiently, I had to introduce the `ImportedSymbolsTracker` which scans the top-level imports of a file and allows them to be checked quickly, without having to go through the type checker. It will be useful in the future when verifying that that initializer APIs aren't used in unexpected places.
I've also introduced tests specifically for the `tryParseInitializerApiMember` function so that we can test it in isolation instead of going through the various functions that call into it.
PR Close#54609
Currently, when a `@defer` block contains standalone components that import NgModules with providers, those providers are not available to components declared within the same NgModule. The problem is that the standalone injector is not created for the host component (that hosts this `@defer` block), since dependencies become defer-loaded, thus no information is available at host component creation time.
This commit updates the logic to collect all providers from all NgModules used as a dependency for standalone components used within a `@defer` block. When an instance of a defer block is created, a new environment injector instance with those providers is created.
Resolves#52876.
PR Close#52881
Fixes that initializer functions weren't being recognized if they are aliased (e.g. `import {model as alias} from '@angular/core';`).
To do this efficiently, I had to introduce the `ImportedSymbolsTracker` which scans the top-level imports of a file and allows them to be checked quickly, without having to go through the type checker. It will be useful in the future when verifying that that initializer APIs aren't used in unexpected places.
I've also introduced tests specifically for the `tryParseInitializerApiMember` function so that we can test it in isolation instead of going through the various functions that call into it.
PR Close#54480
Fixes an edge case where a single-line elemnt with a long tag name a closing bracket on a new line was putting the control flow migration into an infinite loop.
Fixes#54587.
PR Close#54588
Template pipeline is now the default template compiler.
A pair of source map tests is failing, related to DI in JIT mode; I will fix and re-enable these during the preview period.
PR Close#54571
ApplicationRef.tick has a loop that will refresh views again that have
an updated signal. This change ensures views marked with the `Dirty`
flag are also considered in this loop, but only inside g3 for now
because this may be considered a breaking change and we need to wait for
v18 to land externally.
PR Close#54572
In rare cases people may use an underscore in their component names, which was not accounted for in the formatting portion of the migration.
fixes: #54532
PR Close#54533
Prior to this fix an incorrect view instance (a dynamically created component
one instead of the root view) was passed to the content query function. Having
incorrect view instance meant that a component instance could not be found.
This is a pre-existing bug, introduction of signal-based queries just surfaced it.
Fixes#54450
PR Close#54457
Currently all triggers are set up to show the placeholder block on the server, except for `on immediate` which is basically a noop. These changes update `on immediate` to match the rest of the triggers.
Fixes#54385.
PR Close#54394
Getting the typing for `ɵunwrapWritableSignal` just right was tricky so these changes add some tests to ensure that we don't regress.
Also reworks the type tester a bit to make it easier to find where to add new test files.
PR Close#54387
Assure that the same readonly array corresponding to the children query results
is returned for cases where a query is marked as dirty but there were no actual
changes to the content of the results array (this can happen if a view is added
and removed thus marking queries as dirty but not influencing final results).
Fixes#54376
PR Close#54392
The newly introduced signal queries would error if no match exists, due to an
invalid read within the query internals.
This commit addresses the crash by allowing there to be no matches.
PR Close#54353
Currently we have two fake copies of `@angular/core` in the compiler tests which can be out of sync and cause inconsistent tests. These changes reuse a single copy instead.
PR Close#54344
This updates some tests to use the public imports from `@angular/core` now that they are available,
and cleans up useless imports and inaccurate names.
PR Close#54334
In some situations, calling `markForCheck` can result in an infinite
loop in seemingly valid scenarios. When a transplanted view is inserted
before its declaration, it gets refreshed in the retry loop of
`detectChanges`. At this point, the `Dirty` flag has been cleared from
all parents. Calling `markForCheck` marks the insertion tree up to the
root `Dirty`. If the declaration is checked again as a result (i.e.
because it has default change detection) and is reachable because its
parent was marked `Dirty`, this can cause an infinite loop. The
declaration is refreshed again, so the insertion is marked for refresh
(again). We enter an infinite loop if the insertion tree always calls
`markForCheck` for some reason (i.e. `{{createReplayObservable() | async}}`).
While the case above does fall into an infinite loop, it also truly is a
problem in the application. While it's not an infinite synchronous loop,
the declaration and insertion are infinitely dirty and will be refreshed
on every change detection round.
Usually `markForCheck` does not have this problem because the `Dirty`
flag is not cleared until the very end of change detection. However, if
the view did not already have the `Dirty` flag set, it is never cleared
because we never entered view refresh. One solution to this problem
could be to clear the `Dirty` flag even after skipping view refresh but
traversing to children.
PR Close#54329
The `subscribe` methods on `ModelSignal` and `OutputEmitter` were marked as `@internal` which will break when the TCB needs to reference them. These changes make them `@deprecated` temporarily so we can address the properly later.
PR Close#54342
Fixes that `ɵunwrapWritableSignal` inferring getter functions as not matching the interface of `WritableSignal` instead of preserving them.
PR Close#54252
In a previous commit the TCB was changed to cast the assignment to an input in order to widen its type to allow `WritableSignal`. This ended up breaking existing inputs whose setter has a wider type than its getter. These changes switch to unwrapping the value on the binding side.
PR Close#54252
Reworks the TCB for two-way bindings to make them simpler and to avoid regressions for two-way bindings to generic inputs. The new TCB looks as follows:
```
var _t1: Dir;
var _t2 = _t1.input;
(_t1 as typeof _t2 | WritableSignal<typeof _t2>) = expression;
```
PR Close#54252
Adds support for model inputs in the framework. `model()` returns a writable signal that implicitly defines a input/output pair that can be used either in two-way bindings to keep two values in sync or by binding individually to the input and output. When the value of the `model` changes, it will emit an event with the current value.
Furthermore, these changes expand two-way bindings to accept `WritableSignal`. This will make it easier to transition existing code to signals in a backwards-compatible way.
Example:
```ts
@Directive({
selector: 'counter',
standalone: true,
host: {
'(click)': 'increment()',
}
})
export class Counter {
value = model(0);
increment(): void {
this.value.update(current => current + 1);
}
}
@Component({
template: `<counter [(value)]="count"/> The current count is: {{count()}}`,
})
class App {
count = signal(0);
}
```
PR Close#54252
This commit improves IDE completion of the `read` option for
signal-based queries.
Currently, TS only matches the first overload when starting out with
defining a query. TS doesn't build up the combination of possible
options from the second overload- so in practice users will only see
IDE completions for the `descendants` option.
This is not a problem for view queries as the only option is `read`, so
TS will always match the overload with the `read` option.
```
class X {
query = contentChild('', {^^ <--
here we should completion for `read` an `descendants`
}
```
PR Close#54280
Andrew Kushnir