The logic in `isCssClassMatching` is only interested in two areas in the attributes:
implicit attributes and the `AttributeMarker.Classes` area, with the first area only
of interest for projection matching, not directive matching. This commit splits these
two searches to make this more apparent.
PR Close#54800
This commit resolves a regression that was introduced when the compiler switched from
`TemplateDefinitionBuilder` (TDB) to the template pipeline (TP) compiler. The TP compiler
has changed the output of
```html
if (false) { <div class="test"></div> }
```
from
```ts
defineComponent({
consts: [['class', 'test'], [AttributeMarker.Classes, 'test']],
template: function(rf) {
if (rf & 1) {
ɵɵtemplate(0, App_Conditional_0_Template, 2, 0, "div", 0)
}
}
});
```
to
```ts
defineComponent({
consts: [[AttributeMarker.Classes, 'test']],
template: function(rf) {
if (rf & 1) {
ɵɵtemplate(0, App_Conditional_0_Template, 2, 0, "div", 0)
}
}
});
```
The last argument to the `ɵɵtemplate` instruction (0 in both compilation outputs) corresponds with
the index in `consts` of the element's attribute's, and we observe how TP has allocated only a single
attribute array for the `div`, where there used to be two `consts` entries with TDB. Consequently,
the `ɵɵtemplate` instruction is now effectively referencing a different attributes array, where the
distinction between the `"class"` attribute vs. the `AttributeMarker.Classes` distinction affects
the behavior: TP's emit causes the runtime to incorrectly match a directive with `selector: '.foo'` to
be instantiated on the `ɵɵtemplate` instruction as if it corresponds with a structural directive!
Instead of changing TP to align with TDB's emit, this commit updates the runtime instead. This uncovered
an inconsistency in selector matching for class names, where there used to be two paths dealing with
class matching:
1. The first check was commented to be a special-case for class matching, implemented in `isCssClassMatching`.
2. The second path was part of the main selector matching algorithm, where `findAttrIndexInNode` was being used
to find the start position in `tNode.attrs` to match the selector's value against.
The second path only considers `AttributeMarker.Classes` values if matching for content projection, OR of the
`TNode` is not an inline template. The special-case in path 1 however does not make that distinction, so it
would consider the `AttributeMarker.Classes` binding as a selector match, incorrectly causing a directive to
match on the `ɵɵtemplate` itself.
The second path was also buggy for class bindings, as the return value of `classIndexOf` was incorrectly
negated: it considered a matching class attribute as non-matching and vice-versa. This bug was not observable
because of another issue, where the class-handling in part 2 was never relevant because of the special-case
in part 1.
This commit separates path 1 entirely from path 2 and removes the buggy class-matching logic in part 2, as
that is entirely handled by path 1 anyway. `isCssClassMatching` is updated to exclude class bindings from
being matched for inline templates.
Fixes#54798
PR Close#54800
Add an internal API to enable and use i18n hydration for testing and development. This helps ensure that we don't accidentally break the current behavior until we are completely ready to roll out i18n support.
PR Close#54784
Currently if an `(output)` listener fails, it will be handled gracefully
by Angular and reported to the `ErrorHandler`.
For programmatic subscriptions with `OutputEmitterRef`, this is not the case.
Instead, as soon as any subscription is failing, all other subsequent
subscription callbacks are not firing anymore.
This commit intends to make this more consistent by gracefully
reporting errors from `OutputEmitterRef#emit` to `ErrorHandler`,
allowing for listener execution to continue.
PR Close#54821
Ensures that all of the functions intended to be run in initializers are in an injection context. This is a stop-gap until we have a compiler diagnostic for it.
PR Close#54761
This commits assert that the repeater instruction gets a reference
to a tracking function. This change will allow us to better track
occurences of https://github.com/angular/angular/issues/53628 -
in certain situations a reference to a tracking function might be
undefiened.
We are not fixing the underlying issue here, just getting better
visibility.
PR Close#54814
Speeds up the retrieval of `DestroyRef` in `EventEmitter` because
`try/catch` is expensive if there is no injection context.
We saw a script time regression in Cloud.
The goldens had to be updated because `getInjectImplementation` is now
referenced. `inject` also references the underlying field, but directly.
This is super minimal overhead of a function exposing the internal
field.
PR Close#54748
This commit updates HTML sanitization logic to avoid infinite loops in case clobbered elements contain fields like `nextSibling` or `parentNode`. Those fields are used for DOM traversal and this update makes sure that those calls return valid results.
Also this commit fixes an issue when clobbering `nodeName` causes JS exceptions.
PR Close#54425
An i18n message effectively acts as a dynamic template: two elements with contiguous instruction indices won't necessarily be contiguous in the DOM.
For that reason, we need to maintain a mapping from instruction index to a physical DOM node in order to hydrate views with i18n, pointing to where hydration for that view should begin.
PR Close#54750
Updates the instruction generation for two-way bindings to only emit the `twoWayBindingSet` call when writing to template variables. Since template variables are constants, it's only allowed to write to them when they're signals. Non-signal values are flagged during template type checking.
Fixes#54670.
PR Close#54714
The `runCallbackOnce` closure is declared not to have any parameters itself, so it is
compatible as `queueMicrotask` callback without the extra closure. This reduces the call
stack by a frame and avoids the extra closure allocation.
PR Close#54801
This commit ensures that render hooks are rerun when a node is attached
or detached. We do not necessarily need to run change detection but DOM
did change so render hooks should execute.
PR Close#54083
This commit updates the `afterRender` and `afterNextRender` hooks to
notify the scheduler (which subsequently schedules change detection)
when created. This makes the hooks similar to `requestAnimationFrame`,
which requests that the browser schedule a rendering operation. This
reqeust is not conditional. Even if there was nothing to repaint, the
`requestAnimationFrame` callback will execute.
In Angular, this is useful because callers of `afterNextRender` don't
necessarily have any way of knowing whether a change detection is even
scheduled. For example, the anchor scrolling with the Angular Router
needs to wait for rendering to complete before attempting to scroll
because rendering can affect the size of the page. However, if the user
is already on the page that the navigation is targeting, such as
navigating to an anchor on the page, there is nothing new for the Router
to render so a render might not even be scheduled.
Related to https://github.com/angular/angular/issues/53985, which
could use `afterNextRender` instead of `setTimeout` to ensure the
scrolling happens in the same frame as the page rendering, but would not
necessarily work without this change (as described above). Note that the
scrolling _cannot_ use a microtask to ensure scrolling happens in the
same frame because `NgZone` will ensure microtasks flush before
change detection, so it would cause the scroll to happen before rendering.
PR Close#54083
In order to serialize and hydrate i18n blocks, we need to be able to walk an AST for the translated message. This AST is generated during normal parsing of the message.
PR Close#54724
For model signals we introduced some sniffing on the return type of a
`.subscribe` invocation- allowing for subscribe to _just_ return a
callback directly to unsubscribe.
This works in practice, but the positive `tCleanup` indices have more
meaning, especially in the context of `DebugElement`. A positive index
indicates a DOM event- so we need to revert this change. This now
surfaced as we made `EventEmitter` return a function + the subscription
via a proxy that ended up `typeof function` --> and broke some tests
where debug element incorrectly invoked non-dom outputs as dom
listeners. We don't need this change with current unsubscribe function
concept.
PR Close#54650
Technically `model()` and `output()` already need to be defined in an
injection context- because `OutputRef` requires this.
To improve the error messaging, this commit asserts this as part of the
top-level entry functions for `model()` and `output()`. Without this
change, the error would mention the `_createOutputRef` internal
function.
PR Close#54650
An `EventEmitter` is a construct owned by Angular that should be
used for outputs as of right now.
As we are introducing the new `OutputRef` interface for the new output
function APIs, we also think `EventEmitter` should implement
`OutputRef`— ensuring all "known" outputs follow the same contract.
This commit ensures `EventEmitter` implements an `OutputRef`
Note: An output ref captures the destroy ref from the current injection
context for clean-up purposes. This is also done for `EventEmitter` in a
backwards compatible way:
- not requiring an injection context. EventEmitter may be used
elsewhere.
- not cleaning up subscriptions/completing the emitter when the
directive/component is destroyed. This would be a change in behavior.
Note 2: The dependency on `DestroyRef` causes it to be retained in all
bundling examples because ironically `NgZone` uses `EventEmitter`- not
for outputs. The code is pretty minimal though, so that should be
acceptable.
`EventEmitter` will now always retain `NgZone. This increases the
payload size slightly around 800b for AIO. Note that the other increases
were coming from previous changes. This commit just pushed it over the
threshold.
PR Close#54650
A model signal is technically an output, at runtime and conceptually.
This commit re-uses the shared output ref logic and ensures the
interfaces match.
PR Close#54650
This commit introduces an addition to `output()` and
`outputFromObservable`()` —called `outputToObservable()`.
The helper lives in the RxJS interop package and allows agnostic
programmatic subscriptions to `OutputRef`s by converting the output
to an observable with `.pipe` etc.
The function is ideally used in all places where you subscribe to an
output programmatically. Those outputs in the future, with the new APIs,
may not be actual RxJS constructs, but abstract `OutputRef`'s that
simply expose a `.subscribe` method. The helper allows you to
agnostically convert outputs to RxJS observables that you can safely
interact with.
The observables are also completed automatically, if possible, when the
owning directive/component is destroyed— Something that is not
guaranteed right now.
PR Close#54650
Introduces a second API in addition to the new `output()` function.
The new function `outputFromObservable()` can be used to declare outputs
using the new `OutputRef` API and `output()` API, while using a custom
RxJS observable as data source.
This is something that is currently possible in Angular and we would
like to keep possible- even though we never intended to support custom
observables aside from RxJS-based `EventEmitter`.
The interop bridges the gap and allows you to continue using
`Subject`, `ReplaySubject`, `BehaivorSubjct,` - or cold custom
observables for outputs. You can still trigger logic only when
the output is subscribed- unlike with imperative `emit`s of
`EventEmitter` or the new `OutputEmitterRef`.
A notable difference is that you need two class members where you
previously could access the `Subject` directly. This is an intentional
trade-off we've made to ensure that all new outputs implement the
`OutputRef` interface and we are exposing a minimal API surface to
consumers of components that currently access the output
programmatically.
PR Close#54650
This commit exposes the new `output()` API with numerous benefits:
- Symmetrical API to `input()`, `model()` etc.
- Fixed types for `EventEmitter.emit`— current `emit` method of
`EventEmitter` is broken and accepts `undefined` via `emit(value?: T)`
- Removal of RxJS specific concepts from outputs. error channels,
completion channels etc. We now have a simple consistent
interface.
- Automatic clean-up of subscribers upon directive/component destory-
when subscribed programmatically.
```ts
@Directive({..})
export class MyDir {
nameChange = output<string>(); // OutputEmitterRef<string>
onClick = output(); // OutputEmitterRef<void>
}
```
Note: RxJS custom observable cases will be handled in future commits via
explicit helpers from the interop.
PR Close#54650
This commit creates the proposed `OutputRef` interface along
with `OutputEmitterRef`:
- `OutputRef` is the consistent interface for all Angular outputs.
- `OutputEmitterRef` is an extension for emitting values. Like
`EventEmitter`.
- subscriptions are cleaned up automatically upon directive/component
destroy.
- emitting is an error when destroyed
- subscribing programmatically is an error when already destroyed.
This commit will also implement the shared output ref runtime construct,
that can be used by `output()`, `outputFromObservable()` and `model()`.
We will manage subscriptions in a simple way, manually, without RxJS.
PR Close#54650
This commit replaces `fake_core` with the real `@angular/core`
output. See previous commit for reasons.
Overall, this commit:
* Replaces references of `fake_core`
* Fixes tests that were testing Angular compiler detection that _would_
already be flagged by type-checking of TS directly. We keep these
tests for now, and add `@ts-ignore` to verify the Angular checks, in
case type checking is disabled in user applications- but it's worth
considering to remove these tests. Follow-up question/non-priority.
* Adds `@ts-ignore` to the tests for `defer` 1P because the property is
marked as `@internal` and now is (correctly) causing failures in the
compiler test environment.
* Fixes a couple of tests with typos, wrong properties etc that
previously weren't detected! A good sign.
PR Close#54650
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
