Fix createPolled firing twice initially (fixes #632)

.changeset/rich-worms-behave.md

@@ -0,0 +1,5 @@
+---
+"@solid-primitives/timer": patch
+---
+
+Fix createPolled firing twice initially (#632)

packages/timer/src/index.ts

@@ -4,8 +4,8 @@ import {
   createEffect,
   untrack,
   Accessor,
-  createComputed,
   SignalOptions,
+  createMemo,
 } from "solid-js";
 import { isServer } from "solid-js/web";
 
@@ -178,11 +178,9 @@ export function createPolled<T>(
   if (isServer) {
     return fn as Accessor<T>;
   }
-  const [polled, setPolled] = createSignal(untrack(fn.bind(void 0, value)), options);
-  const update = () => setPolled(fn);
-  createTimer(update, timeout, setInterval);
-  createComputed(update);
-  return polled;
+  const memo = createMemo(() => createSignal(untrack(fn.bind(void 0, value)), options), options);
+  createTimer(() => memo()[1](fn), timeout, setInterval);
+  return () => memo()[0]();
 }
 
 /**

packages/timer/test/index.test.ts

@@ -1,6 +1,6 @@
 import { batch, createRoot, createSignal } from "solid-js";
 import { describe, test, expect, vi, beforeEach, afterAll, beforeAll } from "vitest";
-import { createTimer } from "../src/index.js";
+import { createPolled, createTimer } from "../src/index.js";
 
 beforeAll(() => {
   vi.useFakeTimers();
@@ -110,3 +110,23 @@ describe("createTimes", () => {
     dispose();
   });
 });
+
+describe("createPolled", () => {
+  test("fn called initially and after timeout", () => {
+    let n = 0
+    const {polled, dispose} = createRoot(dispose => ({
+      polled: createPolled(() => ++n, 100),
+      dispose,
+    }))
+    expect(polled()).toBe(1)
+
+    vi.advanceTimersByTime(100)
+    expect(polled()).toBe(2)
+
+    dispose()
+    expect(polled()).toBe(2)
+
+    vi.advanceTimersByTime(100)
+    expect(polled()).toBe(2)
+  })
+})