When I run tslint on my code I get the following error

functions that return promises must be async

Here is the code

private doSomething(): void {
    fetch(myUrl)
        .then((rsp: Response) => rsp.text()) // <-- gives error
        .then(txt => this.txt = txt);
}

Not sure now how to fix this because the code runs just fine! Any suggestions ?

When I run tslint on my code I get the following error

functions that return promises must be async

Here is the code

private doSomething(): void {
    fetch(myUrl)
        .then((rsp: Response) => rsp.text()) // <-- gives error
        .then(txt => this.txt = txt);
}

Not sure now how to fix this because the code runs just fine! Any suggestions ?

• javascript
• asynchronous
• promise
• async-await
• tslint

• 1 @Kraylog no...that's not how fetch() API works. rsp.text() returns promise – charlietfl Commented Nov 22, 2018 at 16:12
• 1 rsp is the response from Fetch, so I don't think it can be synchronous – Jeanluca Scaljeri Commented Nov 22, 2018 at 16:13
• 1 response.text() returns a promise. developer.mozilla/en-US/docs/Web/API/Body/text; – jordrake Commented Nov 22, 2018 at 16:13
• Are you using the correct Response type? – dotconnor Commented Nov 22, 2018 at 16:15

1 Answer 1

This error message is caused by the tslint rule promise-function-async.

You can adhere to this rule by adding async on your arrow function expression:

.then(async (rsp: Response) => rsp.text())