In the past two-way bindings used to be interpreted as `foo = $event` at the parser level. In #54065 it was changed to preserve the actual expression, because it was problematic for supporting two-way binding to signals. This unintentionally ended up causing the TCB to two-way bindings to look something like `someOutput.subscribe($event => expr);` which does nothing. It largely hasn't been a problem, because the input side of two-way bindings was still being checked, except for the case where the input side of the two-way binding has a wider type than the output side.
These changes re-add type checking for the output side by generating the following TCB instead:
```
someOutput.subscribe($event => {
var _t1 = unwrapSignalValue(this.someField);
_t1 = $event;
});
```
PR Close#59002
Previously the input flags were being generated as a reference to an enum member for better readability and under the assumption that minifiers would inline the values. That doesn't appear to be the case so these changes switch to using the literal values instead.
PR Close#55215
This commit ensures that the new APIs like `input`, `model`, `output`,
or signal-based queries are not accidentally used on fields that have a
problematic visibility/access level that won't work.
For example, queries defined using a private identifier (e.g. `#bla`)
will not be accessible by the Angular runtime and therefore _dont_ work.
This commit ensures:
- `input` is only declared via public and protected fields.
- `output` is only declared via public and protected fields.
- `model` is only declared via public and protected fields.
- signal queries are only declared via public, protected and TS private
fields (`private` works, while `#bla` does not).
Fixes#54863.
PR Close#54981
In order to allow both signals and non-signals in two-way bindings, we have to pass the expression through `ɵunwrapWritableSignal`. The problem is that the language service uses a bundled compiler that is fairly new, but it may be compiling an older version of Angular that doesn't expose `ɵunwrapWritableSignal` (see https://github.com/angular/vscode-ng-language-service/issues/2001).
These changes add a `_angularCoreVersion` flag to the compiler which the language service can use to pass the parsed Angular version to the compiler which can then decide whether to emit the function.
PR Close#54423
