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A generic interface with type constraints accepting a default type

I've created a simple generic interface in typescript

interface DateAdapter<T> {
clone(): T;
}


and I have a simple class which implements said interface

class StandardDateAdapter implements DateAdapter<StandardDateAdapter> {
clone: () => StandardDateAdapter;
}


I then have a generic Options interface which accepts a type extending DateAdapter. By default, I'd like the type argument to be StandardDateAdapter so I set it up like so:

Options

DateAdapter

StandardDateAdapter

interface Options<T extends DateAdapter<T> = StandardDateAdapter> {
until?: T;
}


Unfortunately, typescript doesn't like this and is throwing an error

Type 'StandardDateAdapter' does not satisfy the constraint 'DateAdapter<T>'.
Types of property 'clone' are incompatible.
Type '() => StandardDateAdapter' is not assignable to type '() => T'.
Type 'StandardDateAdapter' is not assignable to type 'T'.


Any ideas how I can work around this? Is this a bug? Thanks!

note: DateAdapter is only generic because I want the return type of clone() to equal the type of the class implementing DateAdapter. I had initially tried clone(): this; in the DateAdapter, but typescript was smart enough to realize that StandardDateAdapter#clone() returning new StandardDateAdapter !== this

DateAdapter

clone()

DateAdapter

clone(): this;

new StandardDateAdapter

this

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