This PR moves the Observable subscription of toSignal outside of the
reactive context. As the result the toSignal calls are allowed in the
computed, effect and all other reactive consumers.
This is based on the reasoning that we already allow signals creation
in a reactive context. Plus a similar change was done to the async pipe
in the https://github.com/angular/angular/pull/50522Fixes#51027
PR Close#51831
Fixes that there was code duplication between the primary entry-point,
the testing entry-point and the rxjs-interop entry-point.
This code duplication resulted in additional code size (really
neglibible here because rxjs-interop did not duplicate large parts of
core, and `testing` is not used in production).
On the other hand though, the duplication resulted in a subtle JIT
dependency tracking issue due to the `depsTracker` no longer being a
singleton. This caused test failures as in:
https://github.com/angular/angular/pull/51415.
PR Close#51500
Extend toSignal to accept any Subscribable (instead of only Observable)
for consistency with AsyncPipe and for broader compatibility with any
observable library (that is compatible with the Subscribable interface).
This is only a type change as the implementation does not use anything
else than the Subscribable interface anyway.
PR Close#50162
This commit introduces an interface for `toSignal` options to mirror that of
`toObservable`, and adjusts docs for both symbols. It also adds the ability
for `toSignal` to manually specify `DestroyRef` (similarly to
`toObservable` accepting an injector) or for `toSignal` automatic cleanup to
be disabled (in which case the subscription persists until the Observable
completes). Either option allows `toSignal` to be used outside of a DI
context, like `toObservable`.
PR Close#50071
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 the code to avoid deep links into the `@angular/core`, which triggers a build issue in apps when a code is referenced.
PR Close#49823
`toObservable` creates an `effect` that watches for updates to the
source signal. We should allow writes to signals in this effect, which
would be consumed by downstream observers.
PR Close#49769
From Ben:
> When dealing with any reactive function call you don't control
> like `observer.next()` (or anything similar), you want to catch the error
> in the producer call, in this case `signal()`. You don't want to catch errors
> in the `observer.next` call itself.
PR Close#49769
The initial value used for signals by default is now `undefined`. In
addition, there is a new option to express that the signal should emit a
value synchronously (`requireSync: true`). When this value is specified,
the function will throw _on creation_ if the subscribing to the
`Observable` does not result in a synchronous emit.
PR Close#49769
This commit implements an RxJS operator `takeUntilDestroyed` which
terminates an Observable when the current context (component, directive,
etc) is destroyed. `takeUntilDestroyed` will inject the current `DestroyRef`
if none is provided, or use one provided as an argument.
PR Close#49154
This commit adds the basic sketch for the implementation of `fromObservable`
and `fromSignal`, the two basic primitives which form the RxJS interop layer
with signals.
PR Close#49154
This commit adds the infrastructure for `@angular/core/rxjs-interop`, a new
core entrypoint which provides bidirectional interoperability between
Angular's built-in reactivity system of synchronous signals, and the RxJS
`Observable` abstraction.
The new entrypoint is set up as an empty shell in this commit, with its
implementation to follow in a followup.
PR Close#49154
