Issue:

You need a simulator for your Xcode UI tests that is not available on the stack that you are using. For example, you wish to run a simulator for an older iOS version.

Possible solutions:

Add the following code in a Script Step (replace 'iOS 13' with the version you need):

gem install xcode-install
xcversion simulators --install='iOS 13'

Note: this does not work for Xcode 14 onwards, as Apple changed how simulators get installed (the previous version can still use this).

For Xcode 14 (and newer versions), there are two ways of downloading additional simulators.

Download iPhone simulators

You can use the xcodes command to install the simulators.

Add the following code in a Script Step (replace 'iOS 15.5' with the version you need):

#!/usr/bin/env bash
# fail if any commands fails
set -e

# install xcodes
brew tap robotsandpencils/made
brew install robotsandpencils/made/xcodes

# Install iOS 15 simulator
sudo xcodes runtimes install "iOS 15.5"

Download tvOS and watchOS

For tvOS and watchOS, you can download the simulator with the following command based on Apple's official document:

xcrun simctl runtime add tvOS_16.1_beta_Simulator_Runtime.dmg

And here's the list of all available tvOS and watchOS simulator runtimes: https://developer.apple.com/download/all/?q=Simulator%20Runtime