MobileSelector. IOS_PREDICATE_STRING value is not accepted as a valid strategy for element identification

[priyeshkpandey]

Description

While automating for iOS Safari, I tried to use Predicate String strategy to identify the elements on a web page. I first tried to find the element with Appium UI and it worked fine and I was able to get element highlighted. The same I used in my code but it threw Unsupported strategy exception from the code. On debugging more using the Appium console in both the cases, I found that the "using" parameter sent in case of the Appium inspector and the value sent from the java_client are different. The inspector sends the value as "predicate string" that works fine. Whereas from the java_client code the MobileSelector has the value of IOS_PREDICATE_STRING as "-ios predicate string" that doesn't work.

Environment

• java client build version or git revision if you use some shapshot: 5.0.0

• Appium server version or git revision if you use some shapshot: 1.7.1

• Desktop OS/version used to run Appium if necessary: Mac OS high Sierra (10.13.2)

• Node.js version (unless using Appium.app|exe) or Appium CLI or Appium.app|exe: 1.2.7

• Mobile platform/version under test: iOS 11.0

• Real device or emulator/simulator: Real Device

Details

PLEASE LOOK AT THE ATTACHED FILE FOR CODE AND LOGS
MobileSelectorValueIssue.docx

Code To Reproduce Issue [ Good To Have ]

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Ecxeption stacktraces

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Link to Appium logs

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[priyeshkpandey]

UPDATE: I noticed something weird. If I use autoWebview capability as true and before calling any findElement(s) set the context to NATIVE_APP then all the identification methods including the predicate string is working fine. Is this something expected or just stumbled upon some workaround for this?