promise/catch-or-return Restriction ​
What it does ​
Ensure that each time a then() is applied to a promise, a catch() must be applied as well. Exceptions are made for promises returned from a function.
Why is this bad? ​
Not catching errors in a promise can cause hard to debug problems or missing handling of error conditions. In the worst case, unhandled promise rejections can cause your application to crash.
Examples ​
Examples of incorrect code for this rule:
javascript
myPromise.then(doSomething);
myPromise.then(doSomething, catchErrors); // catch() may be a little betterExamples of correct code for this rule:
javascript
myPromise.then(doSomething).catch(errors);
function doSomethingElse() {
return myPromise.then(doSomething);
}