`catch-error-name` fails when try/catch is inside a promise that is caught

[sindresorhus]

Discovered in sindresorhus/got#347

Failing tests: 9f9a324

The cause is the .catch(err => err); part. If that is removed it correctly errors that e should be named err.

// @SamVerschueren

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Submitted pull Requests

• #653 catch-error-name: Add nesting tests

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[SamVerschueren]

I found out why this fails. The thing is that the rule is being disabled when we have nesting catch clauses. Let's use the failing test example.

foo.then(() => {
	try {} catch (e) {}
}).catch(err => err);

It might not look like try-catch and the promise .catch are nested, but apparently they are. So I believe that the only way to actually solve this, is by not disabling the rule when having nested catch clauses.

I believe this was allowed because it didn't allow number postfixes etc. But now we have them. So from the documentation

try {
	doSomething();
} catch (anyName) { // Nesting of catch clauses disables the rule
	try {
		doSomethingElse();
	} catch (anyOtherName) {
		// ...
	}
}

Would actually become

try {
	doSomething();
} catch (err) {
	try {
		doSomethingElse();
	} catch (err1) {
		// ...
	}
}

Don't think this can be auto-fixed in one go though. As the fix statement searches if err, err1, ... exists. So the inner try-catch would not detect that we will have an err identifier after fixing. Not sure if we can keep track of this though.

So that's the reason why this fails. Not sure how to go from here.

[sindresorhus]

I'd rather have a working rule than auto-fix, so I'm fine with that compromise. Let's go with:

So I believe that the only way to actually solve this, is by not disabling the rule when having nested catch clauses.

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[doniyor2109]

@sindresorhus Is this issue still active? If it is I can work on this issue?

[sindresorhus]

Go ahead :)