[analyzer]Don't issue alarm in ObjCSuperCallChecker for the super class itself.

[dcoughlin]

Summary

The ObjCSuperCallChecker issues alarms for various Objective-C APIs that require
a subclass to call to its superclass's version of a method when overriding it.
So, for example, it raises an alarm when the -viewDidLoad method in a subclass
of UIViewController does not call [super viewDidLoad].

This patch fixes a false alarm where the analyzer erroneously required the
implementation of the superclass itself (e.g., UIViewController) to call
super.

[jordan_rose]

Thanks for fixing this.

lib/StaticAnalyzer/Checkers/ObjCMissingSuperCallChecker.cpp

 
 /// \brief Determine whether the given class has a superclass that we want
 /// to check. The name of the found superclass is stored in SuperclassName.
 ///
 /// \param D The declaration to check for superclasses.
 /// \param[out] SuperclassName On return, the found superclass name.
 bool ObjCSuperCallChecker::isCheckableClass(const ObjCImplementationDecl *D,
                                             StringRef &SuperclassName) const {
-  const ObjCInterfaceDecl *ID = D->getClassInterface();
+  const ObjCInterfaceDecl *ID = D->getClassInterface()->getSuperClass();
   for ( ; ID ; ID = ID->getSuperClass())
   {
     SuperclassName = ID->getIdentifier()->getName();
     if (SelectorsForClass.count(SuperclassName))
       return true;
   }
   return false;
 }

test/Analysis/superclass.m

 - (void)viewDidUnload;
 - (void)viewDidLoad;
 - (void)viewWillUnload;
 - (void)viewWillAppear:(BOOL)animated;
 - (void)viewWillDisappear:(BOOL)animated;
 - (void)didReceiveMemoryWarning;
 - (void)removeFromParentViewController;
 - (void)transitionFromViewController:(UIViewController *)fromViewController
-  toViewController:(UIViewController *)toViewController 
+  toViewController:(UIViewController *)toViewController
   duration:(NSTimeInterval)duration options:(UIViewAnimationOptions)options
   animations:(void (^)(void))animations
   completion:(void (^)(BOOL finished))completion;
 @end
 @interface UIResponder : NSObject {}
 - (BOOL)resignFirstResponder;
 @end
 @interface NSResponder : NSObject {}

 - (void)viewWillDisappear:(BOOL)animated {}
 - (void)didReceiveMemoryWarning {}
 - (void)removeFromParentViewController {}
 - (BOOL)resignFirstResponder { return 0; }
 - (void)restoreStateWithCoder:(NSCoder *)coder {}
 - (void)encodeRestorableStateWithCoder:(NSCoder *)coder {}
 @end
 
+// Do not warn for the implementation in the superclass itself.
+@implementation UIViewController
+- (void)addChildViewController:(UIViewController *)childController {}
+- (void)viewDidAppear:(BOOL)animated {}
+- (void)viewDidDisappear:(BOOL)animated {}
+- (void)viewDidUnload {}
+- (void)viewDidLoad {}
+- (void)viewWillUnload {}
+- (void)viewWillAppear:(BOOL)animated {}
+- (void)viewWillDisappear:(BOOL)animated {}
+- (void)didReceiveMemoryWarning {}
+- (void)removeFromParentViewController {}
+- (void)transitionFromViewController:(UIViewController *)fromViewController
+  toViewController:(UIViewController *)toViewController
+  duration:(NSTimeInterval)duration options:(UIViewAnimationOptions)options
+  animations:(void (^)(void))animations
+  completion:(void (^)(BOOL finished))completion {}
+@end
+
 // Warn if UIViewController is our superclass and we do not call super
 @interface TestB : UIViewController {}
 @end
 @implementation TestB
 
 - (void)addChildViewController:(UIViewController *)childController {  
   int addChildViewController = 5;
   for (int i = 0; i < addChildViewController; i++)

 
 - (void)restoreStateWithCoder:(NSCoder *)coder {
   [super restoreStateWithCoder:coder];
 }
 - (void)encodeRestorableStateWithCoder:(NSCoder *)coder {
   [super encodeRestorableStateWithCoder:coder];
 }
 @end
 No newline at end of file