UITableViewController subclass designated initializer calls [super initWithStyle:] and asserts on all UITableViewController designated initializers. Crash

Number:rdar://23709930 Date Originated:12/1/2015
Status:Closed Resolved:No
Product:iOS Product Version:8.4
Classification:Crash Reproducible:Always
Link to Project:https://www.dropbox.com/s/rd24tv30wfv9con/TestTableViewControllerDesignatedInitializers.zip?dl=0
Link to Crash: https://www.dropbox.com/s/fk9tvjt388afa3m/TestTableViewControllerDesignatedInitializers.crash?dl=0

I have a subclass of UITableViewController, let's call it TestTableViewController and I only want one designated initializer for it, let's say initWithTitle:

The implementation of initWithTitle: calls [super initWithStyle:] following the guidelines on how designated initializers should call a super designated initializer.

Since I don't want other initializers to be called, I decided to make the 3 designated initializers of the super class unavailable. These are namely:
- (instancetype)initWithStyle:(UITableViewStyle)style NS_DESIGNATED_INITIALIZER;
- (instancetype)initWithNibName:(nullable NSString *)nibNameOrNil bundle:(nullable NSBundle *)nibBundleOrNil NS_DESIGNATED_INITIALIZER;
- (nullable instancetype)initWithCoder:(NSCoder *)aDecoder NS_DESIGNATED_INITIALIZER;

So in TestTableViewController.h I add the NS_UNAVAILABLE to them and in TestTableViewController.m I make them crash like so:

- (instancetype)initWithStyle:(UITableViewStyle)style NS_UNAVAILABLE;
// FIXME:(hponde)
- (instancetype)initWithNibName:(nullable NSString *)nibNameOrNil
                         bundle:(nullable NSBundle *)nibBundleOrNil NS_UNAVAILABLE;
- (nullable instancetype)initWithCoder:(NSCoder *)aDecoder NS_UNAVAILABLE;


- (instancetype)initWithStyle:(UITableViewStyle)style NS_UNAVAILABLE
    [self doesNotRecognizeSelector:_cmd];
    return nil;
- (instancetype)initWithNibName:(nullable NSString *)nibNameOrNil
                         bundle:(nullable NSBundle *)nibBundleOrNil NS_UNAVAILABLE
    [self doesNotRecognizeSelector:_cmd];
    return nil;
- (nullable instancetype)initWithCoder:(NSCoder *)aDecoder NS_UNAVAILABLE
    [self doesNotRecognizeSelector:_cmd];
    return nil;

This causes a crash because of the following chain of calls:
[TestTableViewController initWithTitle:]
[UITableViewController initWithStyle:]
[TestTableViewController initWithNibName:bundle:]

So it seems that [UITableViewController initWithStyle:], a designated initializer, is calling [self initWithNibName:bundle:], another designated initializer. This is a violation of the initialization contract, since designated initializer cannot call another initializer in the same class.

Steps to Reproduce:
1. Build the project attached and run
2. Crash

Expected Results:
Should not crash, I'm following the initialization contracts but UITableViewController is not. And that behavior is opaque to me.

Actual Results:
Crash with the stack:

2015-12-01 11:34:55.439 TestTableViewControllerDesignatedInitializers[2820:20725394]  [31m-[TestTableViewController initWithNibName:bundle:]: unrecognized selector sent to instance 0x7f9c1153e4e0
 [0m2015-12-01 11:34:55.441 TestTableViewControllerDesignatedInitializers[2820:20725394]  [31m*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[TestTableViewController initWithNibName:bundle:]: unrecognized selector sent to instance 0x7f9c1153e4e0'
*** First throw call stack:
	0   CoreFoundation                      0x000000010d6aec65 __exceptionPreprocess + 165
	1   libobjc.A.dylib                     0x000000010d347bb7 objc_exception_throw + 45
	2   CoreFoundation                      0x000000010d6b60ad -[NSObject(NSObject) doesNotRecognizeSelector:] + 205
	3   TestTableViewControllerDesignatedInitializers 0x000000010ce0e84d -[TestTableViewController initWithNibName:bundle:] + 93
	4   UIKit                               0x000000010dd9b831 -[UITableViewController initWithStyle:] + 45
	5   TestTableViewControllerDesignatedInitializers 0x000000010ce0e966 -[TestTableViewController initWithSingleItem:] + 86
	6   TestTableViewControllerDesignatedInitializers 0x000000010ce0e3d3 -[ViewController viewDidLoad] + 115
	7   UIKit                               0x000000010dbd81d0 -[UIViewController loadViewIfRequired] + 738
	8   UIKit                               0x000000010dbd83ce -[UIViewController view] + 27
	9   UIKit                               0x000000010daf3289 -[UIWindow addRootViewControllerViewIfPossible] + 58
	10  UIKit                               0x000000010daf364f -[UIWindow _setHidden:forced:] + 247
	11  UIKit                               0x000000010daffde1 -[UIWindow makeKeyAndVisible] + 42
	12  UIKit                               0x000000010daa3417 -[UIApplication _callInitializationDelegatesForMainScene:transitionContext:] + 2732
	13  UIKit                               0x000000010daa619e -[UIApplication _runWithMainScene:transitionContext:completion:] + 1349
	14  UIKit                               0x000000010daa5095 -[UIApplication workspaceDidEndTransaction:] + 179
	15  FrontBoardServices                  0x00000001102685e5 __31-[FBSSerialQueue performAsync:]_block_invoke_2 + 21
	16  CoreFoundation                      0x000000010d5e241c __CFRUNLOOP_IS_CALLING_OUT_TO_A_BLOCK__ + 12
	17  CoreFoundation                      0x000000010d5d8165 __CFRunLoopDoBlocks + 341
	18  CoreFoundation                      0x000000010d5d7f25 __CFRunLoopRun + 2389
	19  CoreFoundation                      0x000000010d5d7366 CFRunLoopRunSpecific + 470
	20  UIKit                               0x000000010daa4b02 -[UIApplication _run] + 413
	21  UIKit                               0x000000010daa78c0 UIApplicationMain + 1282
	22  TestTableViewControllerDesignatedInitializers 0x000000010ce0e75f main + 111
	23  libdyld.dylib                       0x000000010fc52145 start + 1
	24  ???                                 0x0000000000000001 0x0 + 1
libc++abi.dylib: terminating with uncaught exception of type NSException

iOS 8.4

Does not happen on iOS 9. Since I need to keep iOS 8 support, I can't have the checks

Simulator iPhone 6

'TestTableViewControllerDesignatedInitializers.crash' and 'TestTableViewControllerDesignatedInitializers.zip' were successfully uploaded.


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