refactor(fiber): resumeAsync() returns an UIO<void>

BREAKING CHANGE: resumeAsync returns a void instead of a Fiber

src/internals/FiberContext.ts

@@ -82,7 +82,7 @@ export class FiberContext<E = never, A = never> extends Fiber<E, A>
     return this
   }
 
-  public resumeAsync(cb: (exit: Exit<E, A>) => UIO<void>): UIO<Fiber<E, A>> {
+  public resumeAsync(cb: (exit: Exit<E, A>) => UIO<void>): UIO<void> {
     const eee = <X>(con: (x: X) => Exit<E, A>) => (data: X) => {
       // tslint:disable-next-line: no-use-before-declare
       const cancel = () => this.cancellationList.remove(id)
@@ -91,6 +91,8 @@ export class FiberContext<E = never, A = never> extends Fiber<E, A>
       )
     }
 
-    return FIO.uio(() => this.$resume(eee(Exit.failure), eee(Exit.success)))
+    return FIO.uio(
+      () => void this.$resume(eee(Exit.failure), eee(Exit.success))
+    )
   }
 }

src/main/Fiber.ts

@@ -26,5 +26,5 @@ export abstract class Fiber<E, A> implements ICancellable {
   }
   public abstract resumeAsync(
     cb: (exit: Exit<E, A>) => UIO<void>
-  ): UIO<Fiber<E, A>>
+  ): UIO<void>
 }

test/FIO.test.ts

@@ -382,14 +382,12 @@ describe('FIO', () => {
         assert.strictEqual(a.count, 1)
       })
 
-      it('should return the same fiber', () => {
+      it('should return void', () => {
         const actual = testRuntime().executeSync(
-          FIO.void().fork.chain(fiber =>
-            fiber.resumeAsync(FIO.void).map(_ => _ === fiber)
-          )
+          FIO.void().fork.chain(fiber => fiber.resumeAsync(FIO.void))
         )
 
-        assert.isTrue(actual)
+        assert.isUndefined(actual)
       })
 
       it('should call with  Exit.success', () => {