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
The View Transitions API enables easy animations when transitioning between different DOM states. This commit adds an opt-in feature to the Router which runs the component activation and deactivation logic in the document.startViewTransition callback. If the browser does not support this API, route activation and deactivation will happen synchronously.
resolves#49401
PR Close#51314
Improves the error handling story for after*Render by delegating errors to an ErrorHandler, so that one failure does not break every callback.
PR Close#51662
To further modernize and improve the performance of the i18n digest generation,
The 64-bit aspects of the process now use the native `BigInt` instead of a
custom JavaScript implementation. This removes the need for the big_integer
helper code and associated tests as the code was not used anywhere else in the
framework. Only the `BigInt` constructor, `BigInt.asUintN` function, and
`.toString` function are currently used. `BigInt` literals can unfortunately
not yet be used due to the bazel test devmode setup which compiles the TypeScript
code at an EcmaScript level that does not yet support the literals.
Browser support information:
- BigInt constructor: https://caniuse.com/mdn-javascript_builtins_bigint_bigint
- BigInt asUintN: https://caniuse.com/mdn-javascript_builtins_bigint_asuintn
- BigInt toString: https://caniuse.com/mdn-javascript_builtins_bigint_tostring
PR Close#48321
This is needed to better support native ESM modules and avoid the otherwise necessary deep imports like `zone.js/fesm2015/zone-node.js` due to disallowed directory imports.
PR Close#51652
For redirects, most of the logic between wildcard and regular redirects
is identical. Combine what can be combined there. Once that was done,
the first part of the matching for redirects looks almost identical to the regular
matching. Create helpers and combine simplify code where possible there
as well.
PR Close#51543
This commit updates the return types of the matching functions to only
return an array when more than one return value is actually possible.
PR Close#51543
Reworks the pure functions to use arrow functions with an implicit return instead of function expressions. This allows us to shave off some bytes for each pure function, because we can avoid some of the syntax.
PR Close#51668
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 flag allows message event listeners to prevent callbacks from executing within the NgZone if they contain a special `__ignore_ng_zone__` flag.
This functionality is built with Angular DevTools in mind, where it prevents an infinite change detection loop in inspecting applications that have message event listeners:
CD -> Inspected app emits componentTreeDirty event to DevTools -> DevTools emits event to get new component Tree from Inspected app -> Inspected app message event listener fires -> CD
PR Close#51339
This commit removes the `urlHandlingStrategy` from the public Router's API
BREAKING CHANGE:
`urlHandlingStrategy` has been removed from the Router public API.
This should instead be configured through the provideRouter or RouterModule.forRoot APIs.
PR Close#51631
These changes build on top of #51514 to add support for advanced expressions inside the `track` parameter of `for` loop blocks. There are two different outputs that the compiler can generate:
1. If the tracking function only references the item or `$index`, the compiler generates a pure arrow function as a constant references in the `repeaterCreate` instruction.
2. If the tracking function has references to properties outside of the `for` loop block, the compiler will rewrite those references to go through `this` and generate a function declaration. The runtime will `bind` the declaration to the current component instance so that the rewritten `this` references are resolved correctly.
Advanced tracking expression come with the following limitations to ensure the best possible performance:
1. They can only reference the item, `$index` and properties directly on the component instance. This means that there'll be an error when accessing this like local template variables and references. While we could get this to work, we would have to traverse the context tree at runtime which will degrade the performance of the loop, because it's a linear time operation that is performed on each comparison. Furthermore, allowing local references would require us re-evaluate the list when any one of them has changed.
2. Pipes aren't allowed inside the tracking function.
3. Object literals and pipes used inside the tracking expression will be recreated on each invocation.
PR Close#51618
Adds an instruction that allows us to access the containing component instance directly instead of having to traverse the context tree. This will be necessary for the tracking function of `for` loop blocks.
PR Close#51618
Adds type checking for the contents of `if`, `switch` and `for` blocks.
**Note:** this is just an initial implementation to get some basic type checking working and to figure out the testing setup. We'll need special TCB structures for this syntax so that we can support type narrowing.
PR Close#51570
When `preserveWhitespaces` is enabled, `switch` blocks can end up with content inside their main block due to the indentation that is usually used for the nested cases. This was tripping up the validation that doesn't allow content inside the main block of `switch`.
These changes update the validation to ignore empty text nodes.
PR Close#51570
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 fixes a bug in the change detection algorithm that would
ignore the `OnPush`/dirty flag of a component's host when it is created
dynamically. That is, `OnPush` components that were not marked dirty but
were created as embedded views would have their host bindings and `ngDoCheck`
function always run even if they were not dirty.
BREAKING CHANGE: `OnPush` components that are created dynamically now
only have their host bindings refreshed and `ngDoCheck run` during change
detection if they are dirty.
Previously, a bug in the change detection would result in the `OnPush`
configuration of dynamically created components to be ignored when
executing host bindings and the `ngDoCheck` function. This is
rarely encountered but can happen if code has a handle on the
`ComponentRef` instance and updates values read in the `OnPush`
component template without then calling either `markForCheck` or
`detectChanges` on that component's `ChangeDetectorRef`.
PR Close#51356
This commit refactors the router internals to track state inside a separate
`StateManager`. This helps open the door to managing the state in
different, swappable providers. The current interface needed by the
Router is: `currentUrlTree`, `rawUrlTree`, `browserUrlTree`,
`routerState`, and `handleNavigationEvent` (other properties are because
some router properties are writeable when they shouldn't be). This is
a suprisingly small interface and can hopefully be made smaller in the
future (i.e. removing 1 or more of the 3 tracked of `UrlTree`s).
PR Close#48481
This commit switches the signals library from a bidirectional symmetric
dependency graph using weak references, to a bidirectional _asymmetric_
graph which uses strong references. This is made possible with a reference
counting algorithm which only tracks producer -> consumer references for
effect-like "live" consumers, preventing memory leaks.
The new algorithm should be simpler and faster than the previous
implementation as weak references are fairly slow to create and traverse.
A tradeoff is that non-live consumers must now poll their producers when
read, as they cannot rely on dirty notifications.
As part of this refactoring, the `ReactiveNode` class is replaced with an
interface instead, and methods are moved to standalone functions. This is
paired with instantiating individual signals/computeds via `Object.create`
against a prototype node which contains static or initial values. This
technique, in conjunction with the rest, greatly improves the performance
of node creation.
PR Close#51226
In preparation for adding support for phases to after*Render, which will increase the implementation size, this commit splits out the optional logic so that it can be tree-shaken and dynamically loaded.
PR Close#51541
`NGMODULE_VE_DEPENDENCY_ON_IVY_LIB` was a ViewEngine related error. This commit removes the doc page but keeps a redirection for older versions still throwing this error.
PR Close#51588
The data `Observable` is not updated unless there have been changes to
the object. The current diffing does not look at `symbol` keys of the
object but the `title` property is stored as a private `symbol`. This
commit updates the object diffing to include symbols.
fixes#51401
PR Close#51561
- Emphasized the importance of using the same InjectionToken instance for both provider and injection call.
- Added examples to illustrate correct usages to prevent NullInjectorError.
PR Close#51386
This change aligns the settings between G3 and P3 as `REMOVE_STYLES_ON_COMPONENT_DESTROY_DEFAULT` is already set to `true` internally.
BREAKING CHANGE: `REMOVE_STYLES_ON_COMPONENT_DESTROY` default value is now `true`. This causes CSS of components to be removed from the DOM when destroyed. You retain the previous behaviour by providing the `REMOVE_STYLES_ON_COMPONENT_DESTROY` injection token.
```ts
import {REMOVE_STYLES_ON_COMPONENT_DESTROY} from '@angular/platform-browser';
...
providers: [{
provide: REMOVE_STYLES_ON_COMPONENT_DESTROY,
useValue: false,
}]
```
PR Close#51571
Alan Agius