Previously effects were queued as they became dirty, and this queue was
flushed at various checkpoints during the change detection cycle. The result
was that change detection _was_ the effect runner, and without executing CD,
effects would not execute. This leads a particular tradeoff:
* effects are subject to unidirectional data flow (bad for dx)
* effects don't cause a new round of CD (good/bad depending on use case)
* effects can be used to implement control flow efficiently (desirable)
This commit changes the scheduling mechanism. Effects are now scheduled via
the microtask queue. This changes the tradeoffs:
* effects are no longer limited by unidirectional data flow (easy dx)
* effects registered in the Angular zone will trigger CD after they run
(same as `Promise.resolve` really)
* the public `effect()` type of effect probably isn't a good building block
for our built-in control flow, and we'll need a new internal abstraction.
As `effect()` is in developer preview, changing the execution timing is not
considered breaking even though it may impact current users.
PR Close#51049
This commit updates the logic to add `prefetch on idle` support for defer blocks. Previously, the `on idle` logic was already implemented for the main loading and rendering. This commit reuses the same logic to bring it to the prefetching mechanism.
PR Close#51629
This commit updates the runtime implementation of defer blocks to avoid their triggering on the server. This behavior was described in the RFC (https://github.com/angular/angular/discussions/50716, see "Server Side Rendering Behavior" section): only a placeholder is rendered on the server at this moment. This commit also updates the logic to make sure that the placeholder content is hydrated after SSR.
PR Close#51530
This commit adds an initial implementation of the `{#defer}` block runtime, which supports the `when` conditions. More conditions and basic prefetching support will be added in followup PRs.
PR Close#51347
The runtime `ɵɵsetNgModuleScope` is modified to accept raw scope info as passed to it in local compilation mode. The runtime further registers the ng-module in the deps tracker. Then the runtime `ɵɵgetComponentDepsFactory` is implemented to use the deps tracker to get the component dependencies which leads to a valid and working Angular code.
PR Close#51377
The runtime `ɵɵsetNgModuleScope` is modified to accept raw scope info as passed to it in local compilation mode. The runtime further registers the ng-module in the deps tracker. Then the runtime `ɵɵgetComponentDepsFactory` is implemented to use the deps tracker to get the component dependencies which leads to a valid and working Angular code.
PR Close#51309
An empty runtime is added just to make the local compiled angular files valid to run. A separate PR will implement the runtime in the right way using the deps tracker.
PR Close#51089
The types and interfaces re;ated to the runtime deps tracker are added. Also an empty implementation is added to be completed in follow up PRs (after the interfaces are confirmed in this PR).
The added files are not used anywhere, so the change should not affect anything in anyway.
PR Close#50606
This commit updates an internal hydration logic to make sure that the content of components with i18n blocks is cleaned up before we start rendering it.
Resolves#50627.
PR Close#50644
According to the HTML specification most attributes are defined as strings, however some can be interpreted as different types like booleans or numbers. [In the HTML standard](https://html.spec.whatwg.org/multipage/common-microsyntaxes.html#boolean-attributes), boolean attributes are considered `true` if they are present on a DOM node and `false` if they are omitted. Common examples of boolean attributes are `disabled` on interactive elements like `<button>` or `checked` on `<input type="checkbox">`. Another example of an attribute that is defined as a string, but interpreted as a different type is the `value` attribute of `<input type="number">` which logs a warning and ignores the value if it can't be parsed as a number.
Historically, authoring Angular inputs that match the native behavior in a type-safe way has been difficult for developers, because Angular interprets all static attributes as strings. While some recent TypeScript versions made this easier by allowing setters and getters to have different types, supporting this pattern still requires a lot of boilerplate and additional properties to be declared. For example, currently developers have to write something like this to have a `disabled` input that behaves like the native one:
```typescript
import {Directive, Input} from '@angular/core';
@Directive({selector: 'mat-checkbox'})
export class MatCheckbox {
@Input()
get disabled() {
return this._disabled;
}
set disabled(value: any) {
this._disabled = typeof value === 'boolean' ? value : (value != null && value !== 'false');
}
private _disabled = false;
}
```
This feature aims to address the issue by introducing a `transform` property on inputs. If an input has a `transform` function, any values set through the template will be passed through the function before being assigned to the directive instance. The example from above can be rewritten to the following:
```typescript
import {Directive, Input, booleanAttribute} from '@angular/core';
@Directive({selector: 'mat-checkbox'})
export class MatCheckbox {
@Input({transform: booleanAttribute}) disabled: boolean = false;
}
```
These changes also add the `booleanAttribute` and `numberAttribute` utilities to `@angular/core` since they're common enough to be useful for most projects.
Fixes#8968.
Fixes#14761.
PR Close#50420
This commit updates hydration logic to support a scenario where a view container that was hydrated and later on projected to a component that skips hydration. Currently, such projected content is extracted from the DOM (since a component that skips hydration needs to be re-created), but never added back, since the current logic treats such content as "already inserted".
Closes#50175.
PR Close#50199
This commit adds an LView flag to indicate that a view is a "signal"
view and updates view creation code to correctly set the flag
based on the declaration component metadata.
PR Close#49988
It's likely that the flag and counters used to track transplanted views
needing a refresh will be reused to signal views as well. The two follow
a similar rule: While the parents might not be "Dirty", there is still a
child/descendant view somewhere that needs to be refreshed during change
detection.
PR Close#50000
The LViewFlags are using manually written 0bxxxxx numbers which can be very hard to read
once there are more than a handful of 0s and 1s. The bit shifting feels a lot more
legible.
PR Close#49987
This commit adds the `signals: boolean` property to the internal
directive/component metadata. This does not add it to the public API
yet, as the feature has no internal support other than compiler
detection.
PR Close#49981
Currently, non-destructive hydration for i18n blocks is not supported (but support is coming!).
This commit updates the serialization logic from throwing an error when it comes across an i18n
block to annotating a component with a skip hydration flag.
PR Close#49722
This commit updates the `effect` primitive and significantly changes the
timing of effect execution.
Previously, effects were scheduled via the microtask queue. This commit
changes effects to run throughout the change detection process instead.
Running effects this way avoids needing additional rounds of change
detection to resolve effects, with the tradeoff that they're harder to use
for model-to-model synchronization (which can be seen as a good thing).
PR Close#49641
This commit consolidates the `RendererFactory` and `Sanitizer` properties
of `LView` onto a single object, the `LViewEnvironment`. These properties
are both set from DI when the root view is created, and not overridden when
child views are created (but inherited from the parent view).
This is a precursor commit to adding the `EffectManager` into the
`LViewEnvironment`.
PR Close#49641
This commit updates the `LView` in Angular to be a `Consumer` of
signals. If a signal is read when executing a template, it marks the
view dirty. In addition, if a signal is read when executing host
bindings, it also marks views dirty.
One interesting thing about signal reads in host bindings
is that they perform a bit better than what we can do with today's
APIs. In order to re-execute host bindings for an `OnPush` component that
might have changed, you would probably inject `ChangeDetectorRef` and call
`markForCheck`. This will mark the _current component_ and parents
dirty. However, host bindings are executed as part of refreshing the
_parent_ so there is really no need to re-execute the current component
if the only thing that changed is the host bindings. When a signal is
read in host bindings, it marks the parent dirty and not the component
that defined the host binding.
Additionally, this commit avoids allocating a full consumer for each
`LView` by re-using a consumer until template execution results in a
signal read. At this point, we assign that consumer to the `LView` and
create a new consumer to "tentatively" use for the future `LView`
template executions.
Co-authored-by: Dylan Hunn <github@dylanhunn.com>
PR Close#49153
This commit adds serialization and hydration logic for content projection.
While hydration for regular elements relies on their location in the TNode tree, the content projection may move elements around, so in order to hydrate them correcty, the runtime needs some extra information. This commit adds a serialization logic that adds element locations (instructions on how to navigate to a particular element from another known location of other element) into the hydration state for the following cases:
- when a TNode is a first element in projection segment (other nodes are linked from that node)
- when a TNode's next sibling is different before and after projection (we serialize extra info about the template-based sibling)
- when a TNode's previous sibling was a content projection (i.e. `<ng-content>` slot), because we can not rely on the previous element in this case (projection happens at a later point)
PR Close#49454
This commit adds serialization and hydration logic for content projection.
While hydration for regular elements relies on their location in the TNode tree, the content projection may move elements around, so in order to hydrate them correcty, the runtime needs some extra information. This commit adds a serialization logic that adds element locations (instructions on how to navigate to a particular element from another known location of other element) into the hydration state for the following cases:
- when a TNode is a first element in projection segment (other nodes are linked from that node)
- when a TNode's next sibling is different before and after projection (we serialize extra info about the template-based sibling)
- when a TNode's previous sibling was a content projection (i.e. `<ng-content>` slot), because we can not rely on the previous element in this case (projection happens at a later point)
PR Close#49454
Adds support for marking a directive input as required. During template type checking, the compiler will verify that all required inputs have been specified and will raise a diagnostic if one or more are missing. Some specifics:
* Inputs are marked as required by passing an object literal with a `required: true` property to the `Input` decorator or into the `inputs` array.
* Required inputs imply that the directive can't work without them. This is why there's a new check that enforces that all required inputs of a host directive are exposed on the host.
* Required input diagnostics are reported through the `OutOfBandDiagnosticRecorder`, rather than generating a new structure in the TCB, because it allows us to provide a better error message.
* Currently required inputs are only supported during AOT compilation, because knowing which bindings are present during JIT can be tricky and may lead to increased bundle sizes.
Fixes#37706.
PR Close#49468
This reverts commit 13dd614cd1.
This breaks a g3 Typescript compilation tests where diagnostics are
expected for a missing input in the component.
PR Close#49467
Adds support for marking a directive input as required. During template type checking, the compiler will verify that all required inputs have been specified and will raise a diagnostic if one or more are missing. Some specifics:
* Inputs are marked as required by passing an object literal with a `required: true` property to the `Input` decorator or into the `inputs` array.
* Required inputs imply that the directive can't work without them. This is why there's a new check that enforces that all required inputs of a host directive are exposed on the host.
* Required input diagnostics are reported through the `OutOfBandDiagnosticRecorder`, rather than generating a new structure in the TCB, because it allows us to provide a better error message.
* Currently required inputs are only supported during AOT compilation, because knowing which bindings are present during JIT can be tricky and may lead to increased bundle sizes.
Fixes#37706.
PR Close#49453
This reverts commit 1a6ca68154.
This breaks tests in google3 which might be depending on private APIs. We
need to update these tests before we can land this PR.
PR Close#49449
Adds support for marking a directive input as required. During template type checking, the compiler will verify that all required inputs have been specified and will raise a diagnostic if one or more are missing. Some specifics:
* Inputs are marked as required by passing an object literal with a `required: true` property to the `Input` decorator or into the `inputs` array.
* Required inputs imply that the directive can't work without them. This is why there's a new check that enforces that all required inputs of a host directive are exposed on the host.
* Required input diagnostics are reported through the `OutOfBandDiagnosticRecorder`, rather than generating a new structure in the TCB, because it allows us to provide a better error message.
* Currently required inputs are only supported during AOT compilation, because knowing which bindings are present during JIT can be tricky and may lead to increased bundle sizes.
Fixes#37706.
PR Close#49304
This commit implements hydration support for view containers, which should make `*ngIf`, `*ngFor` and other structural directive work with hydration.
The logic also respects the `ngSkipHydration` flag and skips hydration in such cases.
PR Close#49382
This commit updates the serialization logic to include information about templates that were used to create embedded views. The information is needed during hydration to pick a correct instance of dehydrated view (this logic will be implemented in a followup commit).
PR Close#49382
Before this change `ɵɵdefineDirective` called `ɵɵdefineComponent` under the hood. This is problematic for the consistent component id generation as it could result in hash collisions for certain directives. Directives however do not require an id.
This changes moves common definition generation logic into a separate function that is re-used in `ɵɵdefineDirective` and `ɵɵdefineComponent`.
PR Close#49350
This commit incrementally builds on top of https://github.com/angular/angular/pull/49271 and adds the logic to hydrate elements and text nodes that don't have any Angular features (like *ngIf/*ngFor, etc) and are not content-projected.
The subsequent commits will extend the logic further to support more complex scenarios.
Co-authored-by: Jessica Janiuk <jessicajaniuk@google.com>
Co-authored-by: Andrew Kushnir <akushnir@google.com>
PR Close#49285
Previously (at the early days of Ivy) a TNode used to keep an array of TViews, but the logic was changed since that time, but the `tViews` field remained on TNode interface (+ corresponding typings).
This commit renames TNode.tViews to TNode.tView and cleans up typings.
PR Close#49313
**Important note**: this is a first commit in a series of commits that will be needed
to support non-destructive hydration. Stay tuned for further updates!
This commit lays the foundation on top of which more hydration logic will be
added in follow up PRs. This PR includes:
* Initial serialization of hydration data
* Data transfer of hydration annotations from server side to client
* Accessing hydration info and populating internal data structures
* Initial APIs (currently private) that enable hydration (in a tree-shakable manner)
* Cleanup of annotations post hydration
* Initial test infrastructure and basic test cases
This commit does **not** expose any public APIs. They'll be exposed later, when
more hydration logic is implemented to a state when it can cover most common
use-cases.
Co-authored-by: Jessica Janiuk <jessicajaniuk@google.com>
Co-authored-by: Andrew Kushnir <akushnir@google.com>
PR Close#49271
DestroyRef represents a concept of lifecycle scope where destroy
callbacks can be registered. Such callbacks are automatically
executed when a given scope ends it lifecycle.
In practice the most common lifecycle scopes would be represented by:
- a component or en embedded view;
- instance of `EnvironnementInjector`.
PR Close#49158
This commit updates the `TNode` to include a reference to the previous sibling node. Currently, TNode has references to the next sibling and parent nodes, but in followup changes we'd need to have access to previous TNodes (to determine position of the current node).
PR Close#49223
This commit removes several debug data structures from
the framework runtime. The data structures in question
were introduced in the framework in the past with the
idea of having debugging aid in the form of the human-redable
data structures. It turned out that in practice those
data structures were not used (most of the fwk developers
didn't even know about their existence!), yet we kept
paying the price of maintaining those duplicated (prod
and debug) version of the data structures.
PR Close#48281
Adds the logic that will filter out unexposed inputs/outputs and apply the aliases that the author specified when writing the host directives.
PR Close#47536
`TNode`s have the `directiveStart` and `directiveEnd` properties that indicate the indexes at which directive instances (including components) have been stored. Currently there are several places throughout the codebase which assume that if a component matches a node, its index will always be `directiveStart`.
As far as I can tell, we probably ended up accumulating these assumptions, because we needed a quick way of accessing the component instance and it happened to be conventiently stored at `directiveStart`. The reason why it's always stored at `directiveStart` is likely to match the lifecycle hook execution order from ViewEngine.
With host directives these assumptions won't be valid anymore, because we want the host directives to _always_ execute before the host component that they're on so that the host has a chance to override them. To achieve this we have to insert host directives before the component.
These changes address the issue by introducing a new `TNode.componentOffset` property which indicates the offset after `TNode.directiveStart` at which the component is stored. Furthermore, I've removed the `isComponentHost` flag since it was duplicating the information from `TNode.componentOffset` and I've audited and fixed all the places where we read `directiveStart` to account for the changed data structure.
Reasons for some of the decisions I made along the way:
* In the case of host directives, I decided to go against our current convention of executing the component lifecycle hooks before the directive, because lifeycle hooks are a chance to change the component state (e.g. in `ngOnChanges`) and running the component hooks first would allow the host directives to undo any overrides made by the host.
* I decided to go with a `componentOffset`, instead of a `componentIndex` indicating the exact index the component is at, because as the runtime is set up at the moment, it would be difficult to know what index the component is going to end up at. Another problem is that we appear to have some logic that moves the entire "directive window" by incrementing both `directiveStart` and `directiveEnd`. By using an offset, we don't have to worry about the index remaining correct.
PR Close#47490
Expands the runtime to allow for basic host directives to be invoked within a template. This is achieved by making a second pass over the directives that were matched based on their selectors and producing a new array of directives that include host directives. Note that the ordering in the array is important, because it determines which host bindings and DI tokens will be overwritten.
PR Close#47430
In a previous refactor, the `RootContext` was update to only contain a reference to a component. This commit perform further refactoring to get rid of the `RootContext` altogether, while storing component reference directly on the root view (without the `RootContext` wrapper).
PR Close#47056
This is the compile-time implementation of the `hostDirectives` feature plus a little bit of runtime code to illustrate how the newly-generated code will plug into the runtime. It works by creating a call to the new `ɵɵHostDirectivesFeature` feature whenever a directive has a `hostDirectives` field. Afterwards `ɵɵHostDirectivesFeature` will patch a new function onto the directive definition that will be invoked during directive matching.
For example, if we take the following definition:
```ts
@Directive({
hostDirectives: [HostA, {directive: HostB, inputs: ['input: alias']}]
})
class MyDir {}
```
Will compile to:
```js
MyDir.ɵdir = ɵɵdefineComponent({
features: [ɵɵHostDirectivesFeature([HostA, {
directive: HostB,
inputs: {
input: "alias"
}
}])]
});
```
The template type checking is implemented during directive matching by adding the host directives applied on the host to the array of matched directives whenever the host is matched in a template.
Relates to #8785.
PR Close#46868
The `RootContext` implementation contained a number of fields that were needed to support an experimental `renderComponent` function. The `renderComponent` function was removed, which allows us to cleanup the `RootContext` further.
The only field that remains on the `RootContext` is the list of bootstrapped components. This list is presumably mostly unused right now (it just contains the current component) and further refactoring can happen in a followup PR.
PR Close#46806
