Xcode 7 - Strange cast error that refers to XCUIElement

Question

I've updated my code to XCode 7 and Swift 2.0, now some of my tests fail and I see a list of 40 warnings in the Test build that are completely unrelated with the code they refer to. The warning message is:

"Cast From 'XCUIElement' to unrelated type 'String' always fails"

And this is an example of a row that produces the warning:

if let protocolStr = JSON["version"] as? String{

I'm not using XC user interface tests yet... so I cannot understand why this code is referring to that class. Any idea?

Update: November 9 With XCode 7.1 the issue is still there.

To "fix" it I substituted the AnyObject type with [String:AnyObject]. — MatterGoal, Sep 30 '15 at 11:07

score 10 · Answer 1 · edited Nov 10 '15 at 11:09

10

With Xcode 7.1.1 Not fixed but this workaround helped me:

if let protocolStr = JSON["version"] as AnyObject as! String {

edited Nov 10 '15 at 11:09

Stefan Gehrig

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answered Nov 10 '15 at 11:05

Eis

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We ran into the same issue (Xcode 7.2), and your workaround _actually works_ for us too! But I can't reason why. What was your reasoning for casting this way? – epologee Dec 16 '15 at 12:33
1

I suspect it has something to do with the UI Testing module because this only appears to be a problem when writing unit tests. My guess is there is an extension on `AnyObject` somewhere to add subscripting that returns an XCUIElement as a convenience for writing UI tests. Something like https://developer.apple.com/reference/xctest/xcuielementquery/1500776-subscript that leaks into AnyObject ... – Sebastien Martin Jul 13 '16 at 12:52

ssrobbi · Answer 2 · 2015-09-30T19:30:02.167

2

I think you already fixed your issue, but in case anyone else is looking at this:

The problem is that JSON is of type AnyObject I'm guessing, at it doesn't know that you can index it as a dictionary. If you cast it as [String : AnyObject] before hand it won't give you an error. (like you noticed)

edit: As for why it's giving you that error specifically, I'm not sure. Probably a bug.

edited Sep 30 '15 at 19:30

answered Sep 30 '15 at 19:20

ssrobbi

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This cast doesn't work only with the test target. The application target accepts this cast without any problem. – MatterGoal Oct 01 '15 at 06:16
Nope it didn't work. The issue is still there, and we DON'T have to find a workaround, Apple HAS TO fix this bug. – MatterGoal Nov 09 '15 at 10:52
Hmm, perhaps it was situational for me. And MatterGoal I agree with you, but Apple generally doesn't give a flying f**** what you think they have to do. I've had bugs reported for well over a year they haven't even acknowledged. – ssrobbi Dec 15 '15 at 21:07

score 1 · Answer 3 · edited Feb 27 '16 at 15:28

1

All I had to do was type the key string (“version”) to NSString like so:

if let protocolStr = JSON["version" as NSString] as? String {
    …
}

edited Feb 27 '16 at 15:28

Tunaki

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answered Feb 27 '16 at 15:22

SushiGrass Jacob

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you cannot convert to NSString like this anymore – João Nunes Feb 29 '16 at 12:40

score 1 · Answer 4 · answered Apr 01 '16 at 12:28

1

Xcode 7.2, swift 2.2

Try like this

if let protocolStr = JSON.valueForKey("version") as? String{
     //your code
}

answered Apr 01 '16 at 12:28

Alupotha

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Xcode 7 - Strange cast error that refers to XCUIElement

4 Answers4