The purpose of a finally block is to ensure the cleanup of objects (e.g. closing the file), it is executed after try and catch blocks under any circumstances. Having a return or a thrown exception in a finally block suppresses the propagation of any unhandled exception which was thrown in the try or catch block or overwrite the returned value.

This rule will report on all usages of jump statements (return, break, throw, and continue) from a finally block. Even if it’s guaranteed that no unhandled exception can happen in try or catch blocks, it’s not recommended to use any jump statements inside the finally to have the logic there limited to the "cleanup".

Noncompliant Code Example

async function foo() {
    let result, connection;
    try {
        connection = await connect();
        result = connection.send(1);
    } catch(err) {
        console.error(err.message); // if this line throws, this exception will not be propagated
    } finally {
        connection.close();
        return result;              // Noncompliant
    }
}

Compliant Solution

async function foo() {
    let result, connection;
    try {
        connection = await connect();
        result = connection.send(1);
    } catch(err) {
        console.error(err.message);
    } finally {
        connection.close();
    }
    return result;
}

See