redirect_to_abstract_class_constructor

The redirecting constructor '{0}' can't redirect to a constructor of the abstract class '{1}'.

The analyzer produces this diagnostic when a constructor redirects to a constructor in an abstract class.

The following code produces this diagnostic because the factory constructor in A redirects to a constructor in B, but B is an abstract class:

class A {
  factory A() = B;
}
​
abstract class B implements A {}

If the code redirects to the correct constructor, then change the class so that it isn't abstract:

class A {
  factory A() = B;
}
​
class B implements A {}

Otherwise, change the factory constructor so that it either redirects to a constructor in a concrete class, or has a concrete implementation.