move browser-only rrdom features to the new rrdom package (#913)

packages/rrdom-nodejs/src/polyfill.ts

@@ -0,0 +1,89 @@
+import { RRDocument, RRNode } from './document-nodejs';
+
+/**
+ * Polyfill the performance for nodejs.
+ * Note: The performance api is available through the global object from nodejs v16.0.0.
+ * https://github.com/nodejs/node/pull/37970
+ */
+export function polyfillPerformance() {
+  if (typeof window !== 'undefined' || 'performance' in global) return;
+  ((global as Window & typeof globalThis)
+    .performance as unknown) = require('perf_hooks').performance;
+}
+
+/**
+ * Polyfill requestAnimationFrame and cancelAnimationFrame for nodejs.
+ */
+export function polyfillRAF() {
+  if (typeof window !== 'undefined' || 'requestAnimationFrame' in global)
+    return;
+
+  const FPS = 60,
+    INTERVAL = 1_000 / FPS;
+  let timeoutHandle: NodeJS.Timeout | null = null,
+    rafCount = 0,
+    requests = Object.create(null);
+
+  function onFrameTimer() {
+    const currentRequests = requests;
+    requests = Object.create(null);
+    timeoutHandle = null;
+    Object.keys(currentRequests).forEach(function (id) {
+      const request = currentRequests[id];
+      if (request) request(Date.now());
+    });
+  }
+
+  function requestAnimationFrame(callback: (timestamp: number) => void) {
+    const cbHandle = ++rafCount;
+    requests[cbHandle] = callback;
+    if (timeoutHandle === null)
+      timeoutHandle = setTimeout(onFrameTimer, INTERVAL);
+    return cbHandle;
+  }
+
+  function cancelAnimationFrame(handleId: number) {
+    delete requests[handleId];
+    if (Object.keys(requests).length === 0 && timeoutHandle !== null) {
+      clearTimeout(timeoutHandle);
+      timeoutHandle = null;
+    }
+  }
+
+  (global as Window &
+    typeof globalThis).requestAnimationFrame = requestAnimationFrame;
+  (global as Window &
+    typeof globalThis).cancelAnimationFrame = cancelAnimationFrame;
+}
+
+/**
+ * Try to polyfill Event type.
+ * The implementation of Event so far is empty because rrweb doesn't strongly depend on it in nodejs mode.
+ * Note: The Event class is available through the global object from nodejs v15.0.0.
+ */
+export function polyfillEvent() {
+  if (typeof Event !== 'undefined') return;
+  (global.Event as unknown) = function () {};
+}
+
+/**
+ * Polyfill Node type with RRNode for nodejs.
+ */
+export function polyfillNode() {
+  if (typeof Node !== 'undefined') return;
+  (global.Node as unknown) = RRNode;
+}
+
+/**
+ *  Polyfill document object with RRDocument for nodejs.
+ */
+export function polyfillDocument() {
+  if (typeof document !== 'undefined') return;
+  const rrdom = new RRDocument();
+  (() => {
+    rrdom.appendChild(rrdom.createElement('html'));
+    rrdom.documentElement!.appendChild(rrdom.createElement('head'));
+    rrdom.documentElement!.appendChild(rrdom.createElement('body'));
+  })();
+  global.document = (rrdom as unknown) as Document;
+}