@stdlib/array/fixed-endian-factory allows misaligned byte offsets and fractional lengths
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Descrizione
### Description
I noticed that `@stdlib/array/fixed-endian-factory` accepts `ArrayBuffer` byte offsets that are not aligned to the element size.
For example, `Float32` values use 4 bytes per element, but the constructor currently accepts a `byteOffset` of `2`.
That can lead to fractional array lengths, which seems incorrect and also differs from native `TypedArray` behavior.
### Reproduction
```js
const Float32ArrayFE = require( '@stdlib/array/fixed-endian-float32' );
const buf = new ArrayBuffer( 16 );
const arr = new Float32ArrayFE( 'little-endian', buf, 2 );
console.log( arr.length );
console.log( arr.byteLength );
console.log( arr.byteOffset );
```
Output:
```text
3.5
14
2
```
The native equivalent:
```js
new Float32Array( new ArrayBuffer( 16 ), 2 );
```
throws a `RangeError` because the offset is not aligned to the 4-byte element size.
I also noticed a similar case when the offset itself is aligned, but the remaining number of bytes is not divisible by the element size:
```js
const Float32ArrayFE = require( '@stdlib/array/fixed-endian-float32' );
const arr = new Float32ArrayFE(
'little-endian',
new ArrayBuffer( 10 ),
4
);
console.log( arr.length );
```
This returns:
```text
1.5
```
while native `Float32Array` rejects the equivalent construction.
### Expected behavior
I would expect the constructor to reject byte offsets that are not aligned to `BYTES_PER_ELEMENT`.
And when no explicit length is provided, the remaining buffer size should also be divisible by `BYTES_PER_ELEMENT`.
That would prevent cases where the array ends up with a fractional `length`.
The relevant code seems to be in:
```text
lib/node_modules/@stdlib/array/fixed-endian-factory/lib/main.js
```
Would matching native `TypedArray` alignment behavior be the expected behavior here?
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Direzione di ricerca
Read lib/node_modules/@stdlib/array/fixed-endian-factory/lib/main.js and reproduce the two Float32 examples from the issue. Compare the constructor behavior with native TypedArray alignment rules; done means invalid offsets and non-divisible remaining byte sizes are rejected instead of producing fractional lengths.
Scritto dal modello di indicizzazione a partire dal testo della issue.
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- Stack tecnologico
- javascript
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- data
- Tipo di issue
- Bug
- Difficoltà
- 2/5
- Tempo stimato
- 1-3 ore
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- 82/100