From 6c894a39cc4edbafdfd84eb9ea28de605d067efc Mon Sep 17 00:00:00 2001
From: Dmitry Gozman <dgozman@gmail.com>
Date: Tue, 29 Sep 2020 08:06:01 -0700
Subject: [PATCH] fix(actions): wait for some time before retrying the action

This saves some CPU cycles while waiting for the page to
change the state, e.g. for animations to complete.

Note that retrying logic is only applicable in rare
circumstances like unexpected scroll in the middle of an
action, or some overlay blocking the click. Usually,
action times out in this cases while retrying.
---
 src/server/dom.ts            | 17 ++++++++++++++---
 test/click-timeout-3.spec.ts |  1 +
 2 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/src/server/dom.ts b/src/server/dom.ts
index 2ccb6f71a722b..121b37abe21da 100644
--- a/src/server/dom.ts
+++ b/src/server/dom.ts
@@ -273,11 +273,22 @@ export class ElementHandle<T extends Node = Node> extends js.JSHandle<T> {
 
   async _retryPointerAction(progress: Progress, actionName: string, waitForEnabled: boolean, action: (point: types.Point) => Promise<void>,
     options: types.PointerActionOptions & types.PointerActionWaitOptions & types.NavigatingActionWaitOptions): Promise<'error:notconnected' | 'done'> {
-    let first = true;
+    let retry = 0;
+    // We progressively wait longer between retries, up to 500ms.
+    const waitTime = [0, 20, 100, 500];
     while (progress.isRunning()) {
-      progress.log(`${first ? 'attempting' : 'retrying'} ${actionName} action`);
+      if (retry) {
+        progress.log(`retrying ${actionName} action, attempt #${retry}`);
+        const timeout = waitTime[Math.min(retry - 1, waitTime.length - 1)];
+        if (timeout) {
+          progress.log(`  waiting ${timeout}ms`);
+          await this._evaluateInUtility(([injected, node, timeout]) => new Promise(f => setTimeout(f, timeout)), timeout);
+        }
+      } else {
+        progress.log(`attempting ${actionName} action`);
+      }
       const result = await this._performPointerAction(progress, actionName, waitForEnabled, action, options);
-      first = false;
+      ++retry;
       if (result === 'error:notvisible') {
         if (options.force)
           throw new Error('Element is not visible');
diff --git a/test/click-timeout-3.spec.ts b/test/click-timeout-3.spec.ts
index d3c571223d3e9..712aefdc4750c 100644
--- a/test/click-timeout-3.spec.ts
+++ b/test/click-timeout-3.spec.ts
@@ -54,6 +54,7 @@ it('should timeout waiting for hit target', async ({page, server}) => {
   expect(error.message).toContain('elementHandle.click: Timeout 5000ms exceeded.');
   expect(error.message).toContain('<div id="blocker"></div> intercepts pointer events');
   expect(error.message).toContain('retrying click action');
+  expect(error.message).toContain('waiting 500ms');
 });
 
 it('should report wrong hit target subtree', async ({page, server}) => {