Swift UI Test fails on iphone4s simulator works well with others

Question

I have a login screen in my app then after login view being dismissed a tabbar appears.

App itself works well in all devices/simulators. UI test works in all simulators except iphone 4s.

I think the reason is after login , it takes way too longer to login screen to disappear. So when I try to access tabbar, it throws an exception.

I tried

let tabBarsQuery = app.tabBars
let predicate = NSPredicate(format: "exists == true")
expectationForPredicate(predicate, evaluatedWithObject: tabBarsQuery, handler: nil)
waitForExpectationsWithTimeout(15, handler: nil)

I get following error

failed: caught "NSUnknownKeyException", "[<XCUIElementQuery 0x7e080d40> valueForUndefinedKey:]: this class is not key value coding-compliant for the key exists."

Why expectation is not working? How can I solve this problem?

Did all the devices you used for testing have the exact same iOS firmware? — LinusGeffarth, Dec 23 '15 at 17:44
I set the all simulators to 9.2 and now it is happening in all of them. — SpaceDust__, Dec 23 '15 at 18:09
when I remove `predicate` it works for all of them besides 4s though — SpaceDust__, Dec 23 '15 at 18:12

score 0 · Answer 1 · answered Mar 21 '17 at 16:18

So the issue with this seems to be that for whatever reason, the .exists property does not exist for a collection of XCUIElementQueries. In your example, you could not do app.tabBars.exists. However, you can change your predicate to be:

let predicate = NSPredicate(format: "count > 0")

And that should work.

Swift UI Test fails on iphone4s simulator works well with others

1 Answers1