feat(compiler): add support for compile-time required inputs

[crisbeto]

Adds support for marking a directive input as required. During template type checking, the compiler will verify that all required inputs have been specified and will raise a diagnostic if one or more are missing. Some specifics:

• Inputs are marked as required by passing an object literal with a required: true property to the Input decorator or into the inputs array.
• Required inputs imply that the directive can't work without them. This is why there's a new check that enforces that all required inputs of a host directive are exposed on the host.
• Required input diagnostics are reported through the OutOfBandDiagnosticRecorder, rather than generating a new structure in the TCB, because it allows us to provide a better error message.
• Currently required inputs are only supported during AOT compilation, because knowing which bindings are present during JIT can be tricky and may lead to increased bundle sizes.

Fixes #37706.

[Harpush]

How will it affect strictNullChecks flag? I believe we still need the ! operator? So instead of runtime checks in ngOnInit we can have the compiler throw errors for us. Anyway that's great! Thanks!

[crisbeto]

Note for reviewer: the test_aio_local failure was triggered by these changes, but it's a pre-existing issue. It'll be resolved by #49293.

[elgreco247]

• Required inputs imply that the directive can't work without them. This is why there's a new check that enforces that all required inputs of a host directive are exposed on the host.

As described by @nartc in this tweet (https://twitter.com/Nartc1410/status/1631694281298640896?s=20) enforcing the exposure of required inputs of host directives might be a little bit too rigid concerning the reusability of a directive.

Maybe the configuration object of host directives can be augmented with a property specifying whether the exposure of required inputs should be enforced.

For example {directive: HostDir, inputs: ['inputAlias'], enforceRequiredInputs: false}.

[crisbeto]

I've integrated the changes from #49333 and addressed the remaining feedback.

[AndrewKushnir]

Reviewed-for: public-api

[alxhub]

Reviewed-for: public-api

[jessicajaniuk]

reviewed-for: public-api

[crisbeto]

Carertaker note: one target is failing internally. It doesn't look related to this change.

[alxhub]

This PR was merged into the repository by commit 1a6ca68.

[e-oz]

Are you sure it's merged into 16.0.0-next.3?
I can't find it in 16.0.0-next.3. When I use @input({required: true}) in a directive or a component:

error TS2345: Argument of type '{ required: boolean; }' is not assignable to parameter of type 'string'.

[kbrilla]

it was reverted for some internal issues pt., 17 mar 2023 o 12:15 Evgeniy OZ ***@***.***> napisał(a):

…

Are you sure it's merged into 16.0.0-next.3? I can't find it in 16.0.0-next.3. When I use @input <https://github.com/input>({required: true}) in a directive or a component: error TS2345: Argument of type '{ required: boolean; }' is not assignable to parameter of type 'string'. — Reply to this email directly, view it on GitHub <#49304 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AFKBQQNMNGZJ4BVTGIFY76TW4RBWNANCNFSM6AAAAAAVOJMFJU> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[e-oz]

thanks @kbrilla

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