text: //// [tests/cases/compiler/outModuleConcatCommonjsDeclarationOnly.ts] ////
  
  //// [a.ts]
  export class A { }
  
  //// [b.ts]
  import {A} from "./ref/a";
  export class B extends A { }
  
  
  
  //// [all.d.ts]
  declare module "ref/a" {
      export class A {
      }
  }
  declare module "b" {
      import { A } from "ref/a";
      export class B extends A {
      }
  }
  