TypedArray-related errors with TypeScript 5.7.2

[mourner]

Upgrading TypeScript and then running npm test produces the following errors:

index.js:88:47 - error TS2554: Expected 0-1 arguments, but got 3.

88             this._boxes = new ArrayType(data, byteOffset + 8, numNodes * 4);
                                                 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~

index.js:89:59 - error TS2554: Expected 0-1 arguments, but got 3.

89             this._indices = new this.IndexArrayType(data, byteOffset + 8 + nodesByteSize, numNodes);
                                                             ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

index.js:99:52 - error TS2554: Expected 0-1 arguments, but got 3.

99             this._boxes = new ArrayType(this.data, 8, numNodes * 4);
                                                      ~~~~~~~~~~~~~~~

index.js:100:64 - error TS2554: Expected 0-1 arguments, but got 3.

100             this._indices = new this.IndexArrayType(this.data, 8 + nodesByteSize, numNodes);

I don't know why it fails to pickup the 3-argument version of the typed constructors. Probably related to microsoft/TypeScript#59417? Any help from people more well versed in TypeScript appreciated.

[mourner]

@rbuckton perhaps you could give a hint on what might be wrong here? The typings depend on a union of *Constructor typed array types here, and for some reason it doesn't resolve to the 3-argument version of the constructor after updating from TS 5.6.

[rbuckton]

When you union constructor types, generic signatures must match exactly. Since each constructor type in the union produces a different return type, they are excluded from the resulting set. In the long term, I can look into adding non-generic overloads for these cases. As a workaround, you can define an alternative union for generic use:

type TypedArray<TArrayBuffer extends ArrayBufferLike = ArrayBuffer> = 
    | Uint8Array<TArrayBuffer>
    | Int8Array<TArrayBuffer>
    | Uint16Array<TArrayBuffer>
    | Int16Array<TArrayBuffer>
    | Uint32Array<TArrayBuffer>
    | Int32Array<TArrayBuffer>
    | Float32Array<TArrayBuffer>
    | Float64Array<TArrayBuffer>;

type TypedArrayConstructor = (
    | Uint8ArrayConstructor
    | Int8ArrayConstructor
    | Uint16ArrayConstructor
    | Int16ArrayConstructor
    | Uint32ArrayConstructor
    | Int32ArrayConstructor
    | Float32ArrayConstructor
    | Float64ArrayConstructor
) & {
    new <TArrayBuffer extends ArrayBufferLike = ArrayBuffer>(arrayBuffer: TArrayBuffer, byteOffset?: number, length?: number): TypedArray<TArrayBuffer>;
};

[mourner]

@rbuckton thank you for the prompt response! I can't get it to work so far, getting some errors that are cryptic to me, but perhaps I should just silence the error because it is getting into territory too complicated for simple typing I intended for the library.

My JSDoc looks like this:

/** @template {ArrayBufferLike} T
 * @typedef {Uint8Array<T> | Int8Array<T> | Uint16Array<T> | Int16Array<T> | Uint32Array<T> | Int32Array<T> | Float32Array<T> | Float64Array<T>} TypedArray<T = ArrayBuffer> */

/** @typedef {(Int8ArrayConstructor | Uint8ArrayConstructor | Uint8ClampedArrayConstructor | Int16ArrayConstructor | Uint16ArrayConstructor | Int32ArrayConstructor | Uint32ArrayConstructor | Float32ArrayConstructor | Float64ArrayConstructor) & {new <T extends ArrayBufferLike = ArrayBuffer>(arrayBuffer: T, byteOffset?: number, length?: number): TypedArray<T>}} TypedArrayConstructor */

And one of the errors is:

index.js:44:49 - error TS2345: Argument of type 'Int8ArrayConstructor | Uint8ArrayConstructor | Uint8ClampedArrayConstructor | Int16ArrayConstructor | ... 4 more ... | Float64ArrayConstructor' is not assignable to parameter of type 'TypedArrayConstructor | undefined'.
  Type 'Uint8ClampedArrayConstructor' is not assignable to type 'TypedArrayConstructor | undefined'.
    Type 'Uint8ClampedArrayConstructor' is not assignable to type 'Int8ArrayConstructor & (new <T extends ArrayBufferLike = ArrayBuffer>(arrayBuffer: T, byteOffset?: number | undefined, length?: number | undefined) => TypedArray<...>)'.
      Type 'Uint8ClampedArrayConstructor' is not assignable to type 'Int8ArrayConstructor'.
        The types of 'prototype.filter(...)[Symbol.toStringTag]' are incompatible between these types.
          Type '"Uint8ClampedArray"' is not assignable to type '"Int8Array"'.

44         return new Flatbush(numItems, nodeSize, ArrayType, undefined, data, byteOffset);
                                                   ~~~~~~~~~

[rbuckton]

This is tracked by microsoft/TypeScript#60745.

[rbuckton]

Do the union constituents match what they were previously? From the error you provided it sounds like Uint8ClampedArray might not have been included previously?

[mourner]

@rbuckton good catch, that was one of the problems. I managed to get the typecheck passing in #59, but it looks ugly as hell now — not sure whether I should merge this or wait for new TS versions if they're going to address cases like this...