Remove superfluous promises

[Lord-Kamina]

Removed most if not all unnecessary promises from the FS api. Note, this was tested by running the app on a new profile but my setup isn't giving me any real errors for some reason, so check and/or correct accordingly.

[CLAassistant]

All committers have signed the CLA.

[ebkr]

I've added a couple of comments but it has a bunch of IDE errors so I'll stop reviewing for now.

This is what it looks like in WebStorm (partly due to .catch(return false)):

You'd need to change the type definitions in NodeFsProvider however I don't entirely agree with the type definition changes.

The reason we say we're returning Promise<X> on all of these is because that's quite literally the return type. An async method will always return a Promise regardless and it's somewhat misleading IMO to say that our method isn't returning the same as what it actually is. This is a snippet from MDN to make it a bit clearer:

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/async_function#description.

Basically async x(...): string is always converted implicitly to async x(...): Promise<string> and so we might as well make it clear. Specifying that return type doesn't cause the method to return Promise<Promise<string>>

[ebkr]

1. You can't have return false as a value inside a catch block. A method invocation is required. This would mean it becomes: .catch(() => false) in both cases
2. Is the second catch block necessary? Why can we not just:

Suggested change

	async exists(path: string): boolean {
	await NodeFs.lock.acquire(path, async () => {
	const result = await fs.promises.access(path, fs.constants.F_OK).catch(return false);
	return true;
	}).catch(return false);
	}
	await NodeFs.lock.acquire(path, async () => {
	return await fs.promises.access(path, fs.constants.F_OK).catch(() => false);
	});

[Lord-Kamina]

Hadn't seen these comments. I'll fix them when I've got a minute.

Although, maybe in the long run it'd be better to rethrow/convert to your custom error class?

[ebkr]

.catch( ... throw) does the exact same thing as not having a catch block in the first place. You don't need the catch block.