[@types/node] Export TestContext type from node:test

[jamiebuilds]

It's sometimes useful to be able to create reusable helpers that use t: TestContext from the TestFn

import test from "node:test"
import assert from "node:assert/strict"
import { groupWhile } from "./groupWhile.tsx"

// Would be better if we could import this type
type TestContext = Parameters<NonNullable<Parameters<typeof test>[0]>>[0]

function check(t: TestContext, input: number[], expected: number[][]) {
	let result = groupWhile(input, (item, index, array) => {
		return array[index - 1]! + 1 === item
	})
	t.diagnostic(`result = ${JSON.stringify(result)}`)
	t.diagnostic(`expected = ${JSON.stringify(expected)}`)
	assert.deepEqual(result, expected)
}

test("empty", (t) => {
	check(t, [], [])
})
test("sequential", (t) => {
	check(t, [1, 2, 3, 4, 5, 6], [[1, 2, 3, 4, 5, 6]])
})
test("non-sequential", (t) => {
	check(t, [1, 2, 4, 5], [[1, 2], [4, 5]])
})

[typescript-bot]

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[jehon]

Same problem.
The code is located here: https://github.com/DefinitelyTyped/DefinitelyTyped/blob/master/types/node/test.d.ts#L391
But how do I import that into another file?

[khaosdoctor]

The TestContext is not exported, you would need to add export type TestContext = TestContext at the bottom of this declaration so you could access it through your code.

[jehon]

Thanks for guidance. I just made a PR.

[JohanAlteruna]

I'd also like to see this change; perhaps there are other types in the node:test module that should be exported as well. The Node documentation for version 21 describes this class in detail, although it does state that "...the TestContext constructor is not exposed as part of the API.". IMO, therefore it makes sense for the declarations to somehow export the type but not the class itself.

[khaosdoctor]

Same problem here, I opened another one and completely missed this: #69488

but still fully support this.

[jehon]

PR proposed here: #69496

[khaosdoctor]

Oh darn did the same 🤣 #69497

You will need to backport this to other versions too I think, from v2x current to v18 and v16 though. Wanna switch?