Using an `effect` inside a `computed` is a clear violation of
the conceptual idea of computed's being pure/ side-effect free.
Additionally, scheduling new effects from an existing actively
running effect is likely unintended as this could degrage application
performance or result in unintentional behaviors. Multiple long-living
effects would be scheduled every time the effect expressions runs.
For these reasons, we are explicitly preventing this pitfal, by
disallowing using `effect` inside reactive contexts.
PR Close#52138
Previously getDependenciesForTokenInInjector was unable to determine which node on a view serviced a specific injection. Now it is able to filter out those injections that did not come from the specific node for the NodeInjector passed into it.
Previously getInjectorMetadata was incorrectly looking up DOM elements for some directives (for example NgForOf) where an LContainer was created. Now the LContainer case is handled, and the non LContainer case uses `getFirstNativeNode` to more accurately get the element we want.
PR Close#51719
Adds a check to the viewport cleanup function to prevent it from re-processing elements that have been fully cleaned up, because it can lead to the `IntersectionObserver` being destroyed even though there are still pending triggers. This can happen, because we have cleanup callbacks both for the block is loaded, but also when the placeholder view is destroyed.
Fixes#52113.
PR Close#52115
This commit updates `@defer` logic related to handling `after` and `minimum` parameters tree-shakable.
If `after` or `minimum` was used on a `@loading` or `@placeholder` blocks, compiler generates an extra argument for the `ɵɵdefer` instruction. This extra argument is a reference to a function that brings timer-related code.
PR Close#52042
The error message now contains the code location of the component. It now looks like: "Error: NG01001: Orphan component found! Trying to render the component Main (at $PROJECT_ROOT/src/main.ts:8) without first loading the NgModule ..."
PR Close#51919
The current error stringifier only includes the class name. In this change a new stringifier is added which returns a more helpful string which includes the file path and line number. Note that this is only the case with components, and for other class types (directive, pipes) it will fallback to the current stringifier. Subsequent changes can cover the case of directive and pipes as well.
PR Close#51919
A new field `debugInfo` is added to the component definition. Now the runtime ɵsetClassDebugInfo stores the debug info for components in this new field.
PR Close#51919
This commit updates the tracking of dirty child views to be a flag
rather than a counter. This is a much more simple method and less likely
to get into the same 'always-wrong' situation that could happen with the
counter (if it is off by 1 once, it's off by 1 forever and you either
get infinite change detection or your view is never refreshed).
PR Close#51515
Fixes that, depending on the matching and import order, in some cases we weren't throwing the error saying that a directive matched multiple times on the same element.
Fixes#52072.
PR Close#52073
This commit adds the code to mark newly created embedded views (that represent `@defer` block states) as dirty to indicate that the view sgould be checked during the next change detection cycle.
Resolves#52094.
PR Close#52095
This change removes the `mutate` method from the `WritableSignal` interface and
completely drops it from the public API surface.
The initial API proposal for Angular signals included the mutate method, allowing
in-place modification of JS objects, without changing their references (identity).
This was based on the reasoning that identity change on modification is not necessary
as we can send the “modified” notification through the signals graph.
Unfortunately the signal-specific change notification is lost as soon as we read
signal value outside of a reactive context (outside of a reactive graph).
In other words - any code outside of the Angular signals library can’t know
that an object is modified.
Secondly, to make the mutate method work, we’ve defaulted the signal value equality function
to the one that considers non-primitive values as always different.
This is unfortunate for people working with immutable data structures
(this is notably the case for the popular state management libraries)
as the default equality function de-optimizes memoization in computed,
making the application less performant.
Given the above reasons we prefer to remove the mutate method in the signals library -
at least for now. There are just too many sharp edges and tradeoffs that we don’t fully
understand yet.
BREAKING CHANGE:
The `mutate` method was removed from the `WritableSignal` interface and completely
dropped from the public API surface. As an alternative please use the update method and
make immutable changes to the object.
Example before:
```typescript
items.mutate(itemsArray => itemsArray.push(newItem));
```
Example after:
```typescript
items.update(itemsArray => [itemsArray, …newItem]);
```
PR Close#51986
This commit reorganizes the Angular code a bit, and moves signals into a
newly defined `@angular/core/primitives` location. This will be used inside
g3 to allow non-Angular targets to depend on the signals core without
incurring a dependency on the whole framework.
PR Close#51986
This commit refactors the signals API surface of Angular out of the
//packages/core/src/signals package. This is done in preparation of moving
the core signals package into a new 'primitives' package that's decoupled
from the public API.
PR Close#51986
`provideClientHydration()` accepts new `HydrationFeature` : `HttpTransferCacheOptions`.
`withHttpTransferCacheOptions` accepts an option object:
* `includeHeaders` : list of headers entries to keep in the cache with the request
* `filter` a callback to determine if a request should be cached
* `includePostRequests`: to include POST requests in the allowed methods
Implements some of the features requested in #50117
PR Close#52029
This change removes the `mutate` method from the `WritableSignal` interface and
completely drops it from the public API surface.
The initial API proposal for Angular signals included the mutate method, allowing
in-place modification of JS objects, without changing their references (identity).
This was based on the reasoning that identity change on modification is not necessary
as we can send the “modified” notification through the signals graph.
Unfortunately the signal-specific change notification is lost as soon as we read
signal value outside of a reactive context (outside of a reactive graph).
In other words - any code outside of the Angular signals library can’t know
that an object is modified.
Secondly, to make the mutate method work, we’ve defaulted the signal value equality function
to the one that considers non-primitive values as always different.
This is unfortunate for people working with immutable data structures
(this is notably the case for the popular state management libraries)
as the default equality function de-optimizes memoization in computed,
making the application less performant.
Given the above reasons we prefer to remove the mutate method in the signals library -
at least for now. There are just too many sharp edges and tradeoffs that we don’t fully
understand yet.
BREAKING CHANGE:
The `mutate` method was removed from the `WritableSignal` interface and completely
dropped from the public API surface. As an alternative please use the update method and
make immutable changes to the object.
Example before:
```typescript
items.mutate(itemsArray => itemsArray.push(newItem));
```
Example after:
```typescript
items.update(itemsArray => [itemsArray, …newItem]);
```
PR Close#51821
This commit adds runtime code to support `after` and `minimum` parameters in the `@placeholder` and `@loading` blocks. The code uses the `TimerScheduler` service added earlier for `on timer` triggers.
PR Close#52009
Currently, if there are 2 nested @defer blocks with the same dependency, Angular throws an error at runtime to indicate that there was a duplicate component def in the registry. This commit updates the logic to only append dependencies when they didn't previously exist in the registry.
PR Close#51964
This partially reverts commit a3e17190e7
and deprecates behavior added.
The context of an embedded view ref at some point was switched from a
getter to an actual assignable property. This is something we revert
as it introduces additional complexity for our generated code
(in terms of closures capturing the `ctx`), creates technical
limitations for Angular's internals and the usage pattern is rarely
used (and can be addressed via simple assignments, `Object.assign` or
the use of a proxy if replacing the full context object is still
desirable)
DEPRECATED: Swapping out the context object for `EmbeddedViewRef`
is no longer supported. Support for this was introduced with v12.0.0, but
this pattern is rarely used. There is no replacement, but you can use
simple assignments in most cases, or `Object.assign , or alternatively
still replace the full object by using a `Proxy` (see `NgTemplateOutlet`
as an example).
Also adds a warning if the deprecated
PR Close#51887
When adding a new view flag, you currently need to adjust the last number of the last
3 flags. All of these share the same number so the shifting ones can just use
the base-10 IndexWithinInitPhaseShift.
PR Close#51839
The new list reconcilation algorithm, an alternative to
the DefaultIterableListDiffer. It works by performing updates
in place instead of creating intermediate data describing changes
to apply. For lists expressed as an Array it performs additional
optimizations for the moves and swap scenarios.
The new list diffing approach is meant to be used in the new control
flow and should me much faster as compared to the ngFor with the
DefaultIterableListDiffer.
PR Close#51980
The template pipeline now supports basic forms of `defer` blocks. This includes the `loading`, `placeholder`, and `error` blocks, as well as the loading and placeholder configuration options.
Lazy dependencies and prefetch are not yet implemented.
PR Close#51942
This is a deceptively simple fix for a deep issue. Consider the following template:
```
<button [title]="myTitle" [id]="(auth().identity() | async)" [tabindex]="1">
```
`TemplateDefinitionBuilder` allocates the following variable (binding) slots:
v[0] = [title] binding
v[1] = [id] binding
v[2] = [tabindex] binding
v[3] = pipe binding
v[4] = pipe binding
As you can see, all three top-level property bindings were assigned variable indices. Then, variables for nested expressions were assigned.
Before this change, Template Pipeline would choose the following order:
v[0] = [title] binding
v[1] = [id] binding
v[2] = pipe binding
v[3] = pipe binding
v[4] = [tabindex] binding
With this order, nested expressions have their variables counted and assigned before subsequent top-level property bindings. This results in different variable indices for `pipeBinding` expressions that are not inside the final property binding.
However, this is not just different -- it's actually incorrect! Consider a case like the following:
```
<button [p1]="c ? (a | pipe) : 3" [p2]="b | pipe">
```
These pipe bindings are executed *conditionally*. This means that, because we don't count and assign all the "fixed" variable slots first, i.e. those belonging to the property bindings, their indices might end up incorrect, depending on whether or not a pipeBinding happened as part of the update block.
With this change, we count all variables on top-level ops first, and then descend into all expressions.
PR Close#51961
Fixes an issue where if animations are enabled, deferred blocks don't remove their placeholder blocks immediately from the DOM. The problem is that we register the event handlers in `afterRender` which runs outside the zone, but the logic that removes the DOM nodes during animations is tied to change detection.
These changes resolve the issue by binding the listeners inside the zone. This was the intention from the beginning, I just forgot that `afterRender` runs outside the zone.
Fixes#51970.
PR Close#51971
Currently, there is no change detection scheduled after triggering `on idle` condition, since `requestIdleCallback` is not patched by Zone.js. This commit invokes the callback in NgZone, so that the code that is invoked within the callback can use zones and a new change detection round is scheduled as needed.
Fixes#51973.
PR Close#51975
This API allows for inspection of a given injector to determine it's type (Element, Environment, Null) as well as it's "source".
- For Environment injectors the source is the source of the injector; `injector.source`.
- For Element injectors the name is the DOM Element that created the injector.
- For the Null Injector this is the string `"Null Injector"`.
PR Close#51900
This commit adds hydration support for repeaters (for loops) and empty blocks. The logic looks up a dehydrated view and use this information for hydration. Otherwise, DOM elements for a view are created from scratch.
PR Close#51920
Prior to this change `this.isStable.pipe(first((isStable) => isStable)).toPromise()` had to be done in multiple places across the framework and the Angular CLI see https://github.com/angular/angular-cli/pull/25856#discussion_r1328158846. In the majority of cases an Observable based `isStable` API is not needed. This also removes the need for RXJS operator imports.
PR Close#51807
This commit updates the `if` and `switch` logic to support hydration. The logic attempts to find dehydrated views in containers while processing `if` and `switch` instructions. If a dehydrated is found, its used to further match elements. Otherwise, DOM elements for a view are created from scratch.
PR Close#51915
Previously, dehydrated views lookup was triggered only when ViewContainerRef was injected. The new control flow logic uses lower level APIs, thus having the code only in the ViewContainerRef is not sufficient.
This commit adds the logic to invoke the process of dehydrated views lookup from the `template` instruction, thus enabling it for new control flow instructions as well.
PR Close#51915
This commit updates hydration runtime code to avoid creating an empty array when we can avoid it. Instead, we just check whether the field is `null` directly (without using nullish coalescing).
PR Close#51917
This commit updates runtime logic of defer blocks to schedule a single `requestIdleCallback` for a group of defer blocks created within a single change detection cycle (for example, as a result of a defer block being defined in a for loop).
PR Close#51750
Switches the syntax for blocks from `{#block}{/block}` to `@block {}` based on the feedback from the community.
Read more about the decision-making process in our blog: https://blog.angular.io/meet-angulars-new-control-flow-a02c6eee7843
The existing block types changed in the following ways:
**Conditional blocks:**
```html
<!-- Before -->
{#if cond}
Main content
{:else if otherCond}
Else if content
{:else}
Else content
{/if}
<!-- After -->
@if (cond) {
Main content
} @else if (otherCond) {
Else if content
} @else {
Else content
}
```
**Deferred blocks**
```html
<!-- Before -->
{#defer when isLoaded}
Main content
{:loading} Loading...
{:placeholder} <icon>pending</icon>
{:error} Failed to load
{/defer}
<!-- After -->
@defer (when isLoaded) {
Main content
} @loading {
Loading...
} @placeholder {
<icon>pending</icon>
} @error {
Failed to load
}
```
**Switch blocks:**
```html
<!-- Before -->
{#switch value}
{:case 1}
One
{:case 2}
Two
{:default}
Default
{/switch}
<!-- After -->
@switch (value) {
@case (1) {
One
}
@case (2) {
Two
}
@default {
Default
}
}
```
**For loops**
```html
<!-- Before -->
{#for item of items; track item}
{{item.name}}
{:empty} No items
{/for}
<!-- After -->
@for (item of items; track item) {
{{item.name}}
} @empty {
No items
}
```
PR Close#51891
This commit adds a logic to handle `on immediate` conditions both as a main condition, as well as a prefetching condition (i.e. `prefetch on immediate`).
PR Close#51630
Adds support for `on viewport` and `prefetch on viewport` triggers which will load the deferred content when the element comes into the view.
PR Close#51874
Adds support for `on hover` and `prefetch on hover` triggers. Some code had to be moved around so it could be reused from the `on interaction` triggers.
PR Close#51874
Updates the logic that generates the instructions for the `on interaction` and `prefetch on interaction` triggers to their final shape. Now the instructions take two arguments:
1. `triggerIndex` - index at which to find the trigger in the view where it will be rendered.
2. `walkUpTimes` - tells the runtime how many views up it needs to go to find the trigger element. If the argument is omitted, it means that the trigger is in the same view as the deferred block. A positive number means that the runtime needs to go up X amount of times to find the trigger. A negative number means that the trigger is inside the root view of the placeholder block. Negative numbers are capped at -1 since the placeholder is always in the same position at runtime.
PR Close#51830
The `Writable` type is usefull when we want overwrite readonly properties and we still want to maintain code navigation/reference. It should be use instead of `any` type assertions for example.
PR Close#49754
Paul Gschwendtner