Resolving

Q:  I have a JavaScript test that successfully automates user interactions in the iPhone Simulator under the iOS SDK 4.0. I upgraded to iOS SDK 4.0.1; Instruments displays "Unexpected error in -[UIATarget_0x.. frontMostApp], /SourceCache/UIAutomation_Sim/UIAutomation-37/Framework/UIATargetElements.m line 437" when I run the above script in the iPhone Simulator.

A: You are getting the "Unexpected error in -[UIATarget_0x.. frontMostApp], /SourceCache/UIAutomation_Sim/UIAutomation-37/Framework/UIATargetElements.m line 437" error message because of a bug in Instruments with iOS SDK 4.0.1.

UI Automation is Accessibility based. As such, the Automation instruments reads and writes an accessibility preference file (specified by com.apple.Accessibility.plist) for the iPhone Simulator at

~/Library/Application Support/iPhone Simulator/<version> where <version> is an iOS SDK version.

In iOS SDK 4.0.1, Automation writes the above file at

~/Library/Application Support/iPhone Simulator/4.0

but reads it at

~/Library/Application Support/iPhone Simulator/4.0.1

Automation displays the above error message since com.apple.Accessibility.plist does not exist at its expected location. You can workaround this bug by making a symlink between your iPhone Simulator 4.0 and 4.0.1 folders.

Follow these steps to create a symlink between your iPhone Simulator 4.0 and 4.0.1 folders:

1. Quit Instruments and the iPhone Simulator if they are opened.

2. Run the following commands in the Terminal application on your machine:

   cd ~/Library/Application\ Support/iPhone\ Simulator/

   ln -s 4.0.1 4.0

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