TypeScript/tests/cases/conformance/classes/mixinAbstractClasses.ts
Ron Buckton 0d284e6c26
Add support for abstract constructor types (#36392)
* Add support for abstract constructor types

* Add backwards-compatible overloads for creating/updating constructor types

* Reverting use of 'abstract' in lib/es5.d.ts due to eslint issues

* Update baseline due to reverting lib

* Add error for failing to mark an mixin class as abstract

* Fix declaration/quick info for abstract construct signatures
2021-01-07 17:11:14 -08:00

37 lines
877 B
TypeScript

// @target: esnext
// @declaration: true
interface Mixin {
mixinMethod(): void;
}
function Mixin<TBaseClass extends abstract new (...args: any) => any>(baseClass: TBaseClass): TBaseClass & (abstract new (...args: any) => Mixin) {
abstract class MixinClass extends baseClass implements Mixin {
mixinMethod() {
}
}
return MixinClass;
}
class ConcreteBase {
baseMethod() {}
}
abstract class AbstractBase {
abstract abstractBaseMethod(): void;
}
class DerivedFromConcrete extends Mixin(ConcreteBase) {
}
const wasConcrete = new DerivedFromConcrete();
wasConcrete.baseMethod();
wasConcrete.mixinMethod();
class DerivedFromAbstract extends Mixin(AbstractBase) {
abstractBaseMethod() {}
}
const wasAbstract = new DerivedFromAbstract();
wasAbstract.abstractBaseMethod();
wasAbstract.mixinMethod();