Nullability annotations

Author: tiennou

Classes/git/PBGitRepositoryWatcher.h

@@ -9,6 +9,9 @@
 //
 
 #import <Foundation/Foundation.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
 @class PBGitRepository;
 
 typedef NS_ENUM(NSUInteger, PBGitRepositoryWatcherEventType) {
@@ -31,3 +34,5 @@ extern NSString *kPBGitRepositoryEventPathsUserInfoKey;
 - (void) stop;
 
 @end
+
+NS_ASSUME_NONNULL_END

Classes/git/PBGitRepositoryWatcher.m

@@ -85,6 +85,8 @@ void PBGitRepositoryWatcherCallback(ConstFSEventStreamRef streamRef,
 @implementation PBGitRepositoryWatcher
 
 - (instancetype) initWithRepository:(PBGitRepository *)theRepository {
+	NSParameterAssert(theRepository != nil);
+
     self = [super init];
     if (!self) {
         return nil;