iOS Mobile: Scroll does not work

The problem

The “mobile: scroll” API is not executed as expected. I will describe it in detail.

Environment

• Appium version (or git revision) that exhibits the issue: 1.20.2
• Last Appium version that did not exhibit the issue (if applicable): I can’t remember
• Desktop OS/version used to run Appium: macOS (Big Sur 11.1)
• Node.js version (unless using Appium.app|exe): v15.8.0
• Npm or Yarn package manager: yarn 1.22.5
• Mobile platform/version under test: iOS 14.3
• Real device or emulator/simulator: simulator
• Appium CLI or Appium.app|exe: Appium Cli

Details

1. TheApp

I got the below error message when using “mobile: scroll” API to scroll to a specific element by predicate string, but it seems not to occur in all other applications.

Failed to find scrollable visible parent with 2 visible children

I realized that prescrollSnapshot is always invisible.

https://github.com/appium/WebDriverAgent/blob/master/WebDriverAgentLib/Categories/XCUIElement+FBScrolling.m#L116

if (![snapshot isWDVisible]) {
    return NO;
}

1. IntegrationApp

It scrolls over the target element until timeout

=> I want to help figure out the bug, but I can’t do it yet. If so, please show me some ideas to solve, I will fix it and make a PR.

Link to Appium logs

https://gist.github.com/zcmgyu/53e859fa6013e64ddaa89117fbc6acbf

Code To Reproduce Issue [ Good To Have ]

https://github.com/zcmgyu/appium-ios-mobile-scroll-bug

Run below command

yarn integration-app

yarn the-app

[mykola-mokhnach]

https://developer.apple.com/documentation/xctest/xcuielement/1618666-tap?language=objc If the element exists within a scrollable view but is offscreen, XCTest will attempt to scroll the element onscreen before performing the tap.

[mykola-mokhnach]

Closed because of no response