Apply assert to ensure singletons are only created once.

// FREEBIE

Podfile

@@ -5,8 +5,8 @@ target 'Signal' do
     pod 'SocketRocket',               :git => 'https://github.com/facebook/SocketRocket.git'
     pod 'AxolotlKit',                 git: 'https://github.com/WhisperSystems/SignalProtocolKit.git'
     #pod 'AxolotlKit',                 path: '../SignalProtocolKit'
-    pod 'SignalServiceKit',           git: 'https://github.com/WhisperSystems/SignalServiceKit.git'
-    #pod 'SignalServiceKit',           path: '../SignalServiceKit'
+    #pod 'SignalServiceKit',           git: 'https://github.com/WhisperSystems/SignalServiceKit.git'
+    pod 'SignalServiceKit',           path: '../SignalServiceKit'
     pod 'OpenSSL'
     pod 'SCWaveformView',             '~> 1.0'
     pod 'JSQMessagesViewController'

Podfile.lock

@@ -116,14 +116,14 @@ DEPENDENCIES:
   - OpenSSL
   - PureLayout
   - SCWaveformView (~> 1.0)
-  - SignalServiceKit (from `https://github.com/WhisperSystems/SignalServiceKit.git`)
+  - SignalServiceKit (from `../SignalServiceKit`)
   - SocketRocket (from `https://github.com/facebook/SocketRocket.git`)
 
 EXTERNAL SOURCES:
   AxolotlKit:
     :git: https://github.com/WhisperSystems/SignalProtocolKit.git
   SignalServiceKit:
-    :git: https://github.com/WhisperSystems/SignalServiceKit.git
+    :path: ../SignalServiceKit
   SocketRocket:
     :git: https://github.com/facebook/SocketRocket.git
 
@@ -131,9 +131,6 @@ CHECKOUT OPTIONS:
   AxolotlKit:
     :commit: cbf2f47d59dd54d6d720fe787f835bd767443bb6
     :git: https://github.com/WhisperSystems/SignalProtocolKit.git
-  SignalServiceKit:
-    :commit: 8b5f82eb6d8393074987697cea6986b55fec800e
-    :git: https://github.com/WhisperSystems/SignalServiceKit.git
   SocketRocket:
     :commit: 877ac7438be3ad0b45ef5ca3969574e4b97112bf
     :git: https://github.com/facebook/SocketRocket.git
@@ -161,6 +158,6 @@ SPEC CHECKSUMS:
   UnionFind: c33be5adb12983981d6e827ea94fc7f9e370f52d
   YapDatabase: b1e43555a34a5298e23a045be96817a5ef0da58f
 
-PODFILE CHECKSUM: a060377074cb361576f346a58d1503b3bd708440
+PODFILE CHECKSUM: cb02bca5a68f5b03df77200dae4ce1235a007807
 
 COCOAPODS: 1.2.0

Signal/src/network/PushManager.h

@@ -39,6 +39,8 @@ typedef void (^pushTokensSuccessBlock)(NSString *pushToken, NSString *voipToken)
 
 @interface PushManager : NSObject <PKPushRegistryDelegate>
 
+- (instancetype)init NS_UNAVAILABLE;
+
 + (PushManager *)sharedManager;
 
 /**

Signal/src/network/PushManager.m

@@ -77,6 +77,8 @@
     _callBackgroundTask = UIBackgroundTaskInvalid;
     _currentNotifications = [NSMutableArray array];
 
+    OWSSingletonAssert();
+
     return self;
 }