Interface Substitution Failure

child.ts

interface Bar {
  readonly bar: 'bar';
}

export interface Foo {
  readonly foo: Bar;
}

index.ts

export * from './parent';

parent.ts

import { Foo } from './child';

interface Bang {
  readonly bang: Foo;
}

export interface Fizz {
  readonly fizz: Bang;
}

RESULT.ts

import { Foo } from '/Users/danielbyrne/neo-one/packages/neo-one-typescript-concatenator/src/__data__/test-directories/interfaces/base/child.ts';
interface Bang {
  readonly bang: Foo;
}
export interface Fizz {
  readonly fizz: Bang;
}