innerFrom treats anything with "length" property as an array, even if this anything has iterable implemented
aweppc opened this issue · 0 comments
Describe the bug
Hello! I've encountered an error in rxjs published as latest (7.8.1 as of writing this)
I've built a simple iterable structure for a specific task. It also had a length property, since I needed to check for that in my operator function.
When I've put that iterable object into from
, it did nothing. Some digging showed up that innerFrom
treats anything with length
property as array just by having that said property and not being a function.
Either isArrayLike
should be changed in some way to fit the fromArrayLike
or order of checks should be different, so that iterables that are not arrays, but have length
property, would be treated as iterables
Expected behavior
from({ [Symbol.iterable](): { ... }, get length() { ... } })
should treat argument as iterable
Reproduction code
import './style.css';
import { from } from 'rxjs';
export class Example<T> implements Iterable<T> {
private items: T[] = [];
public add(item: T) {
this.items.push(item);
}
// comment this getter out to see the difference
public get length() {
return this.items.length;
}
private *generator() {
for (let i = 0; i < this.items.length; i++) {
yield this.items[i];
}
}
[Symbol.iterator](): Iterator<T, any, undefined> {
return this.generator();
}
}
const queue = new Example<string>();
queue.add('kek');
queue.add('lol');
queue.add('wut');
for (const value of queue) {
console.log(value);
}
from(queue).subscribe((value) => console.log(value));
// look at the console
// the "for" loop logs values correctly
// while observable thing does that only if "length" getter is commented out
### Reproduction URL
https://stackblitz.com/edit/rxjs-gsebx7?file=index.ts
### Version
7.8.1
### Environment
_No response_
### Additional context
_No response_