promise/no-callback-in-promise Correctness ​
What it does ​
Disallows calling a callback function (cb()
) inside a Promise.prototype.then()
or Promise.prototype.catch()
.
Why is this bad? ​
Directly invoking a callback inside a then()
or catch()
method can lead to unexpected behavior, such as the callback being called multiple times. Additionally, mixing the callback and promise paradigms in this way can make the code confusing and harder to maintain.
Examples ​
Examples of incorrect code for this rule:
js
function callback(err, data) {
console.log("Callback got called with:", err, data);
throw new Error("My error");
}
Promise.resolve()
.then(() => callback(null, "data"))
.catch((err) => callback(err.message, null));
Examples of correct code for this rule:
js
Promise.resolve()
.then((data) => {
console.log(data);
})
.catch((err) => {
console.error(err);
});