TS1058
The return type of an async function must either be a valid promise or must not contain a callable 'then' member.
Async functions cannot return objects with a callable then property as Javascript aggressively flattens promises. Therefore the following is an error:
class A {
async test() {
return {
then() {},
};
}
}See also
Fix: Rename the method/property.
The best fix for this error is to rename the then method on the object you are
returning to something else. chain or map might be appropriate:
class A {
async test() {
return {
chain() {},
};
}
}