Add NoInfer intrinsic type

[Andarist]

closes #14829

There is still some work to be done here (type displays on hover, assignability bug, and maybe more) - but I'm pushing this out to receive an early feedback

cc @RyanCavanaugh

[typescript-bot]

The TypeScript team hasn't accepted the linked issue #14829. If you can get it accepted, this PR will have a better chance of being reviewed.

[sandersn]

@Andarist did you learn anything interesting from the implementation? If so, can you add a report to the end of #14829? Unless @DanielRosenwasser @RyanCavanaugh or @ahejlsberg are interested in taking up this feature in a design meeting, it's likely that this PR will sit until it gets stale.

[Andarist]

@jakebailey would you mind creating a playground for this? :)

[jakebailey]

@typescript-bot pack this

[typescript-bot]

Heya @jakebailey, I've started to run the tarball bundle task on this PR at 86448ff. You can monitor the build here.

[typescript-bot]

Hey @jakebailey, I've packed this into an installable tgz. You can install it for testing by referencing it in your package.json like so:

{
    "devDependencies": {
        "typescript": "https://typescript.visualstudio.com/cf7ac146-d525-443c-b23c-0d58337efebc/_apis/build/builds/149238/artifacts?artifactName=tgz&fileId=E040D91AAAB70FE622A8C39FD6DF27B76C392A7C8C3B48C212D760AAF66AFD4702&fileName=/typescript-5.1.0-insiders.20230313.tgz"
    }
}

and then running npm install.

---

There is also a playground for this build and an npm module you can use via "typescript": "npm:@typescript-deploys/[email protected]".;

[unional]

Hi, I am reading #14829 and trying to add NoInfer<T> to fix the stub() function in type-plus.

An I notice the type type NoInfer<T> = T & { [K in keyof T]: T[K] } there works with the Animal|Dog example but does not work with:

type NoInfer<T> = T & { [K in keyof T]: T[K] }

type RecursivePartial<T> = {
	[P in keyof T]?: T[P] extends (infer U)[]
		? RecursivePartial<U>[]
		: T[P] extends Record<any, any>
		? RecursivePartial<T[P]>
		: T[P]
}

function foo(v: { a: number, b: string }) {}
function stub<T>(v: RecursivePartial<NoInfer<T>>): T { return v as T }

foo(stub({ a: 1 }) // error

// Argument of type '{ a: number; }' is not assignable to parameter of type '{ a: number; b: string; }'.
// Property 'b' is missing in type '{ a: number; }' but required in type '{ a: number; b: string; }'.

It works with the following type: type NoInfer<T> = Or<IsNull<T>, IsUndefined<T>, T, T & {}>
(where Or<A,B,Then,Else>, IsNull<T>, IsUndefined<T> does what their name suggest).

Just want to bring it up so that this test case is covered in your implementation.
🌷

[Andarist]

@RyanCavanaugh Since 5.2 development has started recently - perhaps we could get some current thoughts from the team about this feature? 😉

[andrewbranch]

@typescript-bot pack this

[typescript-bot]

Looks like you're introducing a change to the public API surface area. If this includes breaking changes, please document them on our wiki's API Breaking Changes page.

Also, please make sure @DanielRosenwasser and @RyanCavanaugh are aware of the changes, just as a heads up.

[typescript-bot]

Heya @andrewbranch, I've started to run the tarball bundle task on this PR at 989fa50. You can monitor the build here.

[typescript-bot]

Hey @andrewbranch, I've packed this into an installable tgz. You can install it for testing by referencing it in your package.json like so:

{
    "devDependencies": {
        "typescript": "https://typescript.visualstudio.com/cf7ac146-d525-443c-b23c-0d58337efebc/_apis/build/builds/158991/artifacts?artifactName=tgz&fileId=95BBFD2778E2B6F0853A6F2EF1EAB1A4AF470C0AB105BAD2C44C6707C2F2A1D302&fileName=/typescript-5.4.0-insiders.20231207.tgz"
    }
}

and then running npm install.

---

There is also a playground for this build and an npm module you can use via "typescript": "npm:@typescript-deploys/[email protected]".;

[Andarist]

superseded by #56794