Merge pull request #67 from thefrontside/tm/add-raf

Added Request Animation Frame package

Author: taras

deno.json

@@ -1,7 +1,7 @@
 {
   "imports": {
-    "bdd": "jsr:@std/testing/bdd",
-    "expect": "jsr:@std/expect"
+    "bdd": "jsr:@std/testing@1/bdd",
+    "expect": "jsr:@std/expect@1"
   },
   "compilerOptions": {
     "lib": [
@@ -24,6 +24,7 @@
     "./deno-deploy",
     "./jsonl-store",
     "./fx",
+    "./raf",
     "./task-buffer",
     "./test-adapter",
     "./tinyexec",

raf/README.md

@@ -0,0 +1,19 @@
+# RAF: Request Animation Frame
+
+Subscribe to a stream of Request Animation Frame updates with an Effection
+resource.
+
+---
+
+```ts
+import { each, main, suspend } from "effection";
+import { raf } from "@effectionx/raf";
+
+await main(function* () {
+  for (const frame of yield* each(raf)) {
+    // add your handler code here
+    console.log(frame);
+    yield* each.next();
+  }
+});
+```

raf/deno.json

@@ -0,0 +1,9 @@
+{
+  "name": "@effectionx/raf",
+  "version": "1.0.0-alpha.0",
+  "exports": "./mod.ts",
+  "license": "MIT",
+  "imports": {
+    "effection": "npm:effection@^3"
+  }
+}

raf/mod.ts

@@ -0,0 +1 @@
+export * from "./raf.ts";

raf/raf.test.ts

@@ -0,0 +1,32 @@
+import {
+  caf as cancelAnimationFrame,
+  raf as requestAnimationFrame,
+} from "npm:@essentials/raf@^1.2.0";
+
+import { each, run, sleep, spawn } from "effection";
+import { describe, it } from "bdd";
+import { expect } from "expect";
+import { raf } from "./raf.ts";
+
+Object.assign(globalThis, {
+  requestAnimationFrame,
+  cancelAnimationFrame,
+});
+
+describe("raf", () => {
+  it("subscription", async () => {
+    expect.assertions(1);
+    let count = 0;
+    await run(function* () {
+      yield* spawn(function* () {
+        for (const _ of yield* each(raf)) {
+          count++;
+          yield* each.next();
+        }
+      });
+      yield* sleep(100);
+    });
+
+    expect(count > 5).toBe(true);
+  });
+});

raf/raf.ts

@@ -0,0 +1,20 @@
+import { createSignal, resource, type Stream } from "effection";
+/**
+ * Consume RAF's as a Stream.
+ */
+export const raf: Stream<number, never> = resource(
+  function* (provide) {
+    let signal = createSignal<number, never>();
+    let id = 0;
+    let callback: FrameRequestCallback = (timestamp) => {
+      signal.send(timestamp);
+      id = requestAnimationFrame(callback);
+    };
+    id = requestAnimationFrame(callback);
+    try {
+      yield* provide(yield* signal);
+    } finally {
+      cancelAnimationFrame(id);
+    }
+  },
+);