FiberStoreImpl wip

Author: tim-smart

src/internal/fiberStore.ts

@@ -19,18 +19,21 @@ class FiberStoreImpl<R, E, A> implements FiberStore.FiberStore<R, E, A> {
     readonly runtime: Runtime.Runtime<R>
   ) {}
 
+  // listeners
   private listeners: Array<() => void> = []
-
+  private notify() {
+    for (let i = 0; i < this.listeners.length; i++) {
+      this.listeners[i]()
+    }
+  }
   public subscribe = (listener: () => void) => {
     this.listeners.push(listener)
-
-    if (!this.fiberState && this.stream) {
-      this.run(this.stream)
-    }
-
+    this.maybeResume()
     return () => {
-      this.listeners.splice(this.listeners.indexOf(listener), 1)
-
+      const index = this.listeners.indexOf(listener)
+      if (index >= 0) {
+        this.listeners.splice(index, 1)
+      }
       queueMicrotask(() => {
         if (this.listeners.length === 0) {
           this.interruptIfRunning()
@@ -39,30 +42,29 @@ class FiberStoreImpl<R, E, A> implements FiberStore.FiberStore<R, E, A> {
     }
   }
 
+  // state
   private trackedProps = TrackedProperties.initial()
   private resultBag: ResultBag.ResultBag<E, A> = ResultBag.make(Result.initial(), this.trackedProps)
   private setResult(result: Result.Result<E, A>) {
     TrackedProperties.updateFromResult(this.trackedProps, result)
     this.resultBag = ResultBag.make(result, this.trackedProps)
-    for (let i = 0; i < this.listeners.length; i++) {
-      this.listeners[i]()
-    }
+    this.notify()
   }
   public snapshot = () => {
     return this.resultBag
   }
 
+  // lifecycle
   private stream: Stream.Stream<R, E, A> | undefined = undefined
   private fiberState:
     | {
       readonly fiber: Fiber.RuntimeFiber<never, void>
       readonly interruptedRef: Ref.Ref<boolean>
     }
     | undefined = undefined
-
   public run(stream: Stream.Stream<R, E, A>) {
-    this.stream = stream
     this.interruptIfRunning()
+    this.stream = stream
 
     const interruptedRef = Ref.unsafeMake(false)
     const maybeSetResult = (result: Result.Result<E, A>) =>
@@ -89,7 +91,6 @@ class FiberStoreImpl<R, E, A> implements FiberStore.FiberStore<R, E, A> {
       interruptedRef
     }
   }
-
   public interruptIfRunning() {
     if (this.fiberState) {
       Effect.runFork(
@@ -101,4 +102,9 @@ class FiberStoreImpl<R, E, A> implements FiberStore.FiberStore<R, E, A> {
       this.fiberState = undefined
     }
   }
+  private maybeResume() {
+    if (!this.fiberState && this.stream) {
+      this.run(this.stream)
+    }
+  }
 }