1 files changed, 156 insertions, 0 deletions
diff --git a/remote/test/puppeteer/src/injected/Poller.ts b/remote/test/puppeteer/src/injected/Poller.ts
new file mode 100644
index 0000000000..c6748ebbc4
--- /dev/null
+++ b/remote/test/puppeteer/src/injected/Poller.ts
@@ -0,0 +1,156 @@
+import {
+  createDeferredPromise,
+  DeferredPromise,
+} from '../util/DeferredPromise.js';
+import {assert} from '../util/assert.js';
+
+interface Poller<T> {
+  start(): Promise<T>;
+  stop(): Promise<void>;
+  result(): Promise<T>;
+}
+
+export class MutationPoller<T> implements Poller<T> {
+  #fn: () => Promise<T>;
+
+  #root: Node;
+
+  #observer?: MutationObserver;
+  #promise?: DeferredPromise<T>;
+  constructor(fn: () => Promise<T>, root: Node) {
+    this.#fn = fn;
+    this.#root = root;
+  }
+
+  async start(): Promise<T> {
+    const promise = (this.#promise = createDeferredPromise<T>());
+    const result = await this.#fn();
+    if (result) {
+      promise.resolve(result);
+      return result;
+    }
+
+    this.#observer = new MutationObserver(async () => {
+      const result = await this.#fn();
+      if (!result) {
+        return;
+      }
+      promise.resolve(result);
+      await this.stop();
+    });
+    this.#observer.observe(this.#root, {
+      childList: true,
+      subtree: true,
+      attributes: true,
+    });
+
+    return this.#promise;
+  }
+
+  async stop(): Promise<void> {
+    assert(this.#promise, 'Polling never started.');
+    if (!this.#promise.finished()) {
+      this.#promise.reject(new Error('Polling stopped'));
+    }
+    if (this.#observer) {
+      this.#observer.disconnect();
+    }
+  }
+
+  result(): Promise<T> {
+    assert(this.#promise, 'Polling never started.');
+    return this.#promise;
+  }
+}
+
+export class RAFPoller<T> implements Poller<T> {
+  #fn: () => Promise<T>;
+  #promise?: DeferredPromise<T>;
+  constructor(fn: () => Promise<T>) {
+    this.#fn = fn;
+  }
+
+  async start(): Promise<T> {
+    const promise = (this.#promise = createDeferredPromise<T>());
+    const result = await this.#fn();
+    if (result) {
+      promise.resolve(result);
+      return result;
+    }
+
+    const poll = async () => {
+      if (promise.finished()) {
+        return;
+      }
+      const result = await this.#fn();
+      if (!result) {
+        window.requestAnimationFrame(poll);
+        return;
+      }
+      promise.resolve(result);
+      await this.stop();
+    };
+    window.requestAnimationFrame(poll);
+
+    return this.#promise;
+  }
+
+  async stop(): Promise<void> {
+    assert(this.#promise, 'Polling never started.');
+    if (!this.#promise.finished()) {
+      this.#promise.reject(new Error('Polling stopped'));
+    }
+  }
+
+  result(): Promise<T> {
+    assert(this.#promise, 'Polling never started.');
+    return this.#promise;
+  }
+}
+
+export class IntervalPoller<T> implements Poller<T> {
+  #fn: () => Promise<T>;
+  #ms: number;
+
+  #interval?: NodeJS.Timer;
+  #promise?: DeferredPromise<T>;
+  constructor(fn: () => Promise<T>, ms: number) {
+    this.#fn = fn;
+    this.#ms = ms;
+  }
+
+  async start(): Promise<T> {
+    const promise = (this.#promise = createDeferredPromise<T>());
+    const result = await this.#fn();
+    if (result) {
+      promise.resolve(result);
+      return result;
+    }
+
+    this.#interval = setInterval(async () => {
+      const result = await this.#fn();
+      if (!result) {
+        return;
+      }
+      promise.resolve(result);
+      await this.stop();
+    }, this.#ms);
+
+    return this.#promise;
+  }
+
+  async stop(): Promise<void> {
+    assert(this.#promise, 'Polling never started.');
+    if (!this.#promise.finished()) {
+      this.#promise.reject(new Error('Polling stopped'));
+    }
+    if (this.#interval) {
+      clearInterval(this.#interval);
+    }
+  }
+
+  result(): Promise<T> {
+    assert(this.#promise, 'Polling never started.');
+    return this.#promise;
+  }
+}