Xcode / the iOS Simulator has issues in performance limited environments – Bitrise

Issue:

The root cause of the issue is that Xcode / the iOS Simulator has issues in performance limited environments. This included Virtual Machines (which is how your builds are running on bitrise.io), MacBook Airs, Mac Minis with HDD storage, …

It can happen even if you use Apple’s Xcode Bots CI server on non SSD Mac Mini.

Examples:

UI Tests fail to start
One or more UI Test case hangs

Possible solutions:

As reported in this StackOverflow answer & in this Apple dev forum discussion a possible workaround can be to not to store **XCUIApplication()** in a variable, instead reference / use it directly. E.g. instead of: let app = XCUIApplication() ; ... ; app.launch() do: XCUIApplication().launch()
Others reported that if you add a delay (sleep(10)) after every app.launch() related to your tests, it can leave enough time for Xcode / the iOS Simulator to initialize the Accessibility labels, so that UI Tests can properly find the elements by the Accessibility labels. (Related Apple developer forum discussion)
- Related: remove every explicit app.terminate() in your tearDown() method(s)
Try another Simulator device
Use the Async testing APIs
Some users had success with splitting the tests into multiple Schemes, and running those separately, with separate Test Steps.
- A great article about splitting tests into multiple Schemes: http://artsy.github.io/blog/2016/04/06/Testing-Schemes
Sometimes it’s related to a code which makes Xcode to misbehave
Try another Xcode version.

Issue:

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