Add tsgo (TypeScript 7 native preview) type-check to CI

[veksa]

Summary

TypeScript 7 ships as a native (Go) compiler, distributed today as @typescript/native-preview with a tsgo binary. This PR adds a CI job that type-checks Reselect's type tests with tsgo, and makes the small set of changes needed for the whole typescript_test suite to pass cleanly under both tsc and tsgo. Everything stays green on the existing tsc matrix (5.0 through 5.8), so the day TS 7 becomes the compiler we build with, there's nothing left to fix.

Why

tsgo is close enough that it's worth running in CI today rather than discovering a wall of incompatibilities later. Pointing it at a heavily overload-driven library like Reselect turned out to be a good stress test, and it surfaced a few genuine forward-compatibility items in our config plus one interesting difference in how errors are reported.

What's in here

Config that TypeScript 7 no longer accepts. tsgo rejects a few options that were removed in TS 7, so tsconfig.json needed updating: moduleResolution: "Node" (node10) becomes "bundler", the now-removed baseUrl is dropped, and the paths entries get the leading ./ that TS 7 requires. These are no-ops for tsc 5.x and for the Vitest type tests, which still pass unchanged.

Type-test lib and globals. The typescript_test project pinned lib to just ES2021.WeakRef. Classic tsc pulls the rest of the standard library in through that file's reference chain, but tsgo doesn't, so it's now ES2021 (a superset — same APIs). It also picks up types: ["node"] because tsgo doesn't auto-include @types/node globals the way tsc does, and a couple of src files touch console/process.

The negative type tests. This is the bulk of the diff, and it's mostly deletions. Our @ts-expect-error assertions for the "this call should be a type error" cases spanned multi-line calls, with the directive sitting on the line tsc happens to report the overload error on. tsgo reports the same errors — it just pins them to the specific offending argument instead — which left those directives looking unused. Since @ts-expect-error is tied to the exact next line, there's no multi-line arrangement that satisfies both compilers, so each of these calls is now collapsed onto a single line with one leading @ts-expect-error. The assertions stay exactly as strict; they simply stop caring about where the squiggle is drawn. Positive tests and everything else are untouched.

One relaxed assertion. createStructuredSelector(...).dependencies is currently inferred in a different tuple order by tsgo than by tsc. That single spot swaps its exact-tuple expectExactType for a membership check on the same three signatures, with a comment explaining why. The runtime ordering is still covered by the regular unit tests.

The wiring. @typescript/native-preview is added as a dev dependency, there's a type-check:tsgo script (tsgo --noEmit -p typescript_test/tsconfig.json, mirroring test:typescript), and a new test-types-tsgo job in the CI workflow that runs it.

Notes

The dev build is pinned rather than tracking latest so the job doesn't turn red on an unrelated upstream change. When TS 7 stabilises this can move to a real release and, if we ever want it, into the version matrix alongside the tsc runs.

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[EskiMojo14]

isn't typescript 7 in stable release now, so we don't need the preview package? it should be enough just to add 7 to the matrix

we also follow the DefinitelyTyped window so you can remove anything older than 5.6

[veksa]

@EskiMojo14

Good catch, TS 7 is stable now so the preview package was overkill. Dropped the native-preview dep and the separate tsgo job — just added 7.0 (and 6.0) to the type matrix so it runs with the normal tsc like everything else. Also trimmed the versions below 5.6 to match the DefinitelyTyped window. Checked locally that the types pass on both 6.0.3 and 7.0.2.

[EskiMojo14]

i'll merge #764 once CI passes on that, so this can then be rebased and we can get a better CI picture