[Trent Millar (trentmillar)]

Fixes #61680

Adds <TArrayBuffer extends ArrayBufferLike = ArrayBuffer> overloads to the remaining TypedArray constructor signatures ((), length, ArrayLike, Iterable, and ArrayLike | ArrayBuffer) across the lib files so new Uint8Array<ArrayBufferLike>(source) and super(...) in Uint8Array<ArrayBufferLike> subclasses work.

Kept the non-generic TypedArray<ArrayBuffer> overloads first so new Uint8Array(10) and #60934 aren't affected. Also made sure to hit the 0-arg es2017.typedarrays and Float16Array constructors while I was in there so none of the typed arrays are left out.

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Checklist:

• There is an associated issue in the Backlog milestone
• Code is up-to-date with the main branch
• Ran npx hereby test
• Ran npx hereby lint
• Ran npx hereby check:format
• Added/updated compiler tests validating the change

[Copilot]

🔵 Needs a closer look

The new typed-array overloads can incorrectly claim SharedArrayBuffer backing for an ordinary ArrayBuffer, allowing calls that type-check but fail at runtime.

No open issues 🎉

What changed in this PR

Addresses #61680 by extending the compiler’s bundled TypedArray declarations so explicit buffer type arguments work with additional constructor forms and subclass super(...) calls.

Changes:

• Adds generic overloads for empty, length, array-like, iterable, and union inputs across TypedArray families.
• Keeps existing non-generic overloads first to preserve default inference and compatibility with #60934.
• Expands compiler regression cases for generic construction and subclassing.

File	Description
tsc/​testdata/​tests/​cases/​compiler/​typedArrayConstructorOverloads.ts	Adds generic constructor and subclass regression cases.
tsc/​internal/​bundled/​libs/​lib.es5.d.ts	Adds generic length, array-like, and union overloads.
tsc/​internal/​bundled/​libs/​lib.es2025.float16.d.ts	Extends Float16Array constructor overloads.
tsc/​internal/​bundled/​libs/​lib.es2020.bigint.d.ts	Extends both BigInt typed-array constructors.
tsc/​internal/​bundled/​libs/​lib.es2017.typedarrays.d.ts	Adds generic zero-argument constructors.
tsc/​internal/​bundled/​libs/​lib.es2015.iterable.d.ts	Adds generic iterable constructors.

_{Review effort: Balanced}

[Trent Millar (trentmillar)]

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