App Store review incorrectly flags category methods as overriding SPI

Number:rdar://7414099 Date Originated:20-Nov-2009 02:21 PM
Status:Open Resolved:
Product:Other Product Version:3.0
Classification:Serious Bug Reproducible:I Didn't Try
20-Nov-2009 02:21 PM Andrew Wooster:
RogueSheep recently blogged [0] that an app of theirs that uses the Three20 [1] framework was rejected because:

"""The notice from Apple indicated that we had used a private method of UIViewController called previousViewController. Interestingly enough, we did not explicitly use this call anywhere in our code. Looking a bit into the version of the Three20 library we were using revealed that it coincidentally contained a category that added a method to UIViewController called previousViewController."""

I believe this to be a false positive. Apologies in advance if I'm wrong. I'm working on very little information here. [*]

Attached is a test project which should trigger the false positive in your static analyzer (or whatever you're using). It's hard to tell, because I haven't seen this myself and don't have access to the tool itself.

Three20 does have a category on UIViewController which adds the method "-previousViewController". However, Apple does not (as tested with -respondsToSelector:) have a private method called -previousViewController in UIViewController.

The closest I can find, which may be triggering the problem, is the private method -previousViewController defined for UINavigationController, a subclass of UIViewController.

However, the private method on UINavigationController should override the category method defined by Three20, so the category method should not cause any problems in Apple code.

So, I believe whichever tool you're using to determine whether an app is using SPI is flawed and producing false positives.

[*] I am, however, an interested party, in that I work on several apps which use Three20, and could thus be rejected for this reason.


Apple has resolved this issue.

The project file referenced above is available at:

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