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 the `ApplicationRef.isStable` API to account for
pending rendering task. This is needed as once a pending rendering task
is done, new macrotask and microtask could be created which previously caused these not
to be intercepted and thus ignored when doing SSR.
PR Close#50425
Injecting `ViewContainerRef` into a component makes it effectively a container. The leave animation wasn't triggered on containers before this fix.
fixes angular#48667
PR Close#48705
When an embedded view injector is present anywhere above a node in the tree, the `Self` flag was effectively ignored. With this change, embedded view injectors are not checked at all when the `Self` flag is present, because resolution should stop at the current node before reaching any embedded view injector(s).
Fixes#49959
PR Close#50270
As a preliminary work for #50399, I'd like to add this test to see the effect of treeshaking that will be brought by the incomming refactoring of the AnimationModule.
This is animations test ported to standalone.
PR Close#50413
Fixes that the host directives feature was incorrectly throwing the conflicting alias error when an aliased binding was being exposed under the same alias.
Fixes#48951.
PR Close#50364
Related to #50272 and #18970, this improves the error message of NG100 by including the class name of the component where the error was triggered.
PR Close#50286
Unlike the current signature where the input argument must a function, this change allows an input of any type to be passed to the `isSignal` function.
PR Close#50035
This commit removes unnecessary transfer state escaping and updates this process to be done by the means of a `replacer` and `reviver` method as this removes the need to export the escaping and unescaping methods.
The only thing that we need to escape is `<script` and `</script` which are done by the browsers, but not Node.js.
PR Close#50201
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
Rather than maintaining separate traversal functions that act differently, this change
updates the change detection traversal to share more code and use different modes
to control the type of traversal being performed.
PR Close#50005
Prior to this commit we tried to retrieve transferred state on both browser and server. Doing this on the server was redundant and could causes issues as `document` might be undefined.
Closes#50138
PR Close#50144
Due to assertNoImageDistortion using clientWidth and clientHeight, and these properties returning integers, rounding errors occur that exceed the aspect ratio tolerance.
Increasing the tolerance could hide actual distortion so correcting the calculation to use floats would be best and could even allow for a lower tolerance.
PR Close#49889
The image distortion detection performed uses clientWidth/clientHeight which includes the padding.
This leads to images with padding being detected as distorted while they are not and distortion being masked by padding.
PR Close#49889
Both the render and update instructions live in the same file and are
only separated via a "render*" vs "refresh*" naming convention. This
commit moves these functions to completely separate files.
PR Close#50017
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
This adds context to the error message in the case that a DOM node is not found during the hydration process. It outputs the expected DOM structure based on the lView and tNode rather than an unhelpful text message.
PR Close#49977
As described in
https://github.com/angular/angular/discussions/49681#discussioncomment-5628930,
if an `Observable` created from a signal with `toObservable` is
subscribed to in a template, it will initially have `null` as the value.
Immediately after the template is done executing, effects are flushed
and this results in the `AsyncPipe` getting a new value before the
`checkNoChanges` pass, resulting in `ExpressionChanged` error.
```
template: '{{obs$ | async}}'
...
obs$ = toObservable(signal(0));
```
Instead, this commit updates the `toObservable` to synchronously emit
the initial value to the Observable stream.
Side note here: We don't exactly encourage this pattern. Instead of
using `AsyncPipe`, the template should just read signals.
PR Close#49894
This commit updates hydration logic to hanlde a case when the same component is used multiple times in a template and in some of those cases, component is opted-out of hydration, for example:
```
<cmp ngSkipHydration />
<cmp />
```
Previously, the first occurrence of the `<cmp>` would result in storing the `ssrId` on a TView as `null` (since hydration is disabled for the component) and the second component instance reused the `null` as a value, thus also skipping hydration.
With the changes from this commit, the `ssrId` would be set when we come across a hydratable instance. We also make sure that the `ssrId` value never changes after we first set it to a non-`null` value.
PR Close#49943
This change explicitly resets a reactive consumer before setting inputs
on directive instances. This is to assure that any potential input setters
do _not_ run in the reactive context.
PR Close#49906
When binding an array to `class` like `[class]="['foo', 'bar']"`, the runtime treats it the same as a literal binding with all the values being `true`, e.g. `{foo: true, bar: true}`. While object literals can only have string keys, arrays can have any value which can lead to errors if the array contains non-string values.
These changes add some logic to stringify the keys and ignore invalid ones.
Fixes#48473.
PR Close#49924
This fix assures that templates functions executed in the creation mode
are run outside of the reactive context. This avoids the situation where
signal reads in a directive constructor (executed as part of the creation
mode) would mark the host component as dirty.
Fixes#49871
PR Close#49883
Currently, the `ViewRef.rootNodes` output is missing anchor (comment) nodes for inner `ViewContainerRef`s,
when an achor node was created for that instance of a `ViewContainerRef` (which happens in all cases except
when an <ng-container> was used as a host for a view container).
This issue affects hydration logic, which relies on the number of root nodes within a view to properly determine
segments in DOM that belong to a particular view.
Resolves#49849.
PR Close#49867
It might happen that the lifecycle scope represented by DestroyRef becomes
invalid before an onDestroy hook is registered (ex. injector or component
instance got destroyed). In such cases registration of the onDestroy hooks
should no longer be possible.
Fixes#49658
PR Close#49804
The new asReadonly method on the WritableSignal interface makes
it possible to create readonly instance of a writable signal.
Readonly signals can be accessed to read their value,
but can't be changed using set, update or mutate methods.
PR Close#49802
Angular doesn't support IE anymore. We can remove the workarounds related to IE.
Some workarounds are keep because of the support of domino but the comments related to IE are removed.
PR Close#49763
This change makes is possible to use async functions
(ones returning a promise) as effect run functions.
To make it possible, the signature of the effect function
changed: effect cleanup function is registered now
(using a dedicated callback passed to the effect creation)
instead of being returned from the effect function.
PR Close#49783
This reverts commit 2279f4d4620eba083a9832ed096890b69a25ec42.
Reverting that commit based off PR feedback that this change should only affect the parsing of sergments and node encoding of the url
PR Close#47332
fix router segment name parsing to allow segements to container an unscaped = character. Currently if you have a url like /some-site/folder=/some-file then then middle segment "folder=" will stop parsing at the = sign and register that part of the path as just "folder"
Fixes#21381
PR Close#47332
This commits updates the render to able to handle the slight differences between platform-server and platform-browser.
This is needed to eventually be able to remove `ServerRendererFactory2` and `EmulatedEncapsulationServerRenderer2` from platform-server.
PR Close#49630
This commit adds a hook to `WritableSignal` that is called whenever the
signal's value is updated via the mutation API. This hook allows consumers
to implement logic which is synchronous with signal sets (e.g. executing
effects). It's currently unused.
PR Close#49708
