Guard against not being signed in with an error

mas-cli.xcodeproj/project.pbxproj

@@ -24,7 +24,7 @@
 		ED0F23891B87543D00AE40CD /* DownloadQueueObserver.swift in Sources */ = {isa = PBXBuildFile; fileRef = ED0F23881B87543D00AE40CD /* DownloadQueueObserver.swift */; };
 		ED0F238B1B87569C00AE40CD /* Downloader.swift in Sources */ = {isa = PBXBuildFile; fileRef = ED0F238A1B87569C00AE40CD /* Downloader.swift */; };
 		ED0F238D1B8756E600AE40CD /* Error.swift in Sources */ = {isa = PBXBuildFile; fileRef = ED0F238C1B8756E600AE40CD /* Error.swift */; };
-		ED0F23901B87A56F00AE40CD /* StoreAccount.swift in Sources */ = {isa = PBXBuildFile; fileRef = ED0F238F1B87A56F00AE40CD /* StoreAccount.swift */; };
+		ED0F23901B87A56F00AE40CD /* ISStoreAccount.swift in Sources */ = {isa = PBXBuildFile; fileRef = ED0F238F1B87A56F00AE40CD /* ISStoreAccount.swift */; };
 		EDEAA0C01B51CE6200F2FC3F /* StoreFoundation.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = EDEAA0BF1B51CE6200F2FC3F /* StoreFoundation.framework */; };
 		EDEAA17D1B5C579100F2FC3F /* CommerceKit.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = EDEAA17C1B5C579100F2FC3F /* CommerceKit.framework */; };
 		F5F01044EC3065C6EBAB95D7 /* BoxType.swift in Sources */ = {isa = PBXBuildFile; fileRef = F0E87CFA5E6371893D5B1807 /* BoxType.swift */; };
@@ -60,7 +60,7 @@
 		ED0F23881B87543D00AE40CD /* DownloadQueueObserver.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = DownloadQueueObserver.swift; sourceTree = "<group>"; };
 		ED0F238A1B87569C00AE40CD /* Downloader.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = Downloader.swift; sourceTree = "<group>"; };
 		ED0F238C1B8756E600AE40CD /* Error.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = Error.swift; sourceTree = "<group>"; };
-		ED0F238F1B87A56F00AE40CD /* StoreAccount.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = StoreAccount.swift; sourceTree = "<group>"; };
+		ED0F238F1B87A56F00AE40CD /* ISStoreAccount.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = ISStoreAccount.swift; sourceTree = "<group>"; };
 		EDEAA0BF1B51CE6200F2FC3F /* StoreFoundation.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = StoreFoundation.framework; path = /System/Library/PrivateFrameworks/StoreFoundation.framework; sourceTree = "<absolute>"; };
 		EDEAA0C31B51CEE400F2FC3F /* CDStructures.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = CDStructures.h; sourceTree = "<group>"; };
 		EDEAA0C41B51CEE400F2FC3F /* CKBook.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = CKBook.h; sourceTree = "<group>"; };
@@ -352,7 +352,7 @@
 			children = (
 				ED0F238A1B87569C00AE40CD /* Downloader.swift */,
 				ED0F23881B87543D00AE40CD /* DownloadQueueObserver.swift */,
-				ED0F238F1B87A56F00AE40CD /* StoreAccount.swift */,
+				ED0F238F1B87A56F00AE40CD /* ISStoreAccount.swift */,
 			);
 			path = AppStore;
 			sourceTree = "<group>";
@@ -642,13 +642,13 @@
 				B80C5DDD38A8F7EB6F320697 /* Errors.swift in Sources */,
 				5918483F96256CDAC88FF450 /* HelpCommand.swift in Sources */,
 				ED0F237F1B87522400AE40CD /* Install.swift in Sources */,
+				ED0F23901B87A56F00AE40CD /* ISStoreAccount.swift in Sources */,
 				ED0F23831B87533A00AE40CD /* ListInstalled.swift in Sources */,
 				ED0F23851B87536A00AE40CD /* ListUpdates.swift in Sources */,
 				ED031A7C1B5127C00097692E /* main.swift in Sources */,
 				DE39BCA91D1BC3D876711677 /* MutableBox.swift in Sources */,
 				92828DCD99CED47F54242776 /* Option.swift in Sources */,
 				1CC607DA6B900AA3FEC3F6D8 /* Result.swift in Sources */,
-				ED0F23901B87A56F00AE40CD /* StoreAccount.swift in Sources */,
 				7858BCFB4D5A4251DE998CE4 /* Switch.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;

mas-cli/AppStore/ISStoreAccount.swift

@@ -0,0 +1,17 @@
+//
+//  ISStoreAccount.swift
+//  mas-cli
+//
+//  Created by Andrew Naylor on 22/08/2015.
+//  Copyright (c) 2015 Andrew Naylor. All rights reserved.
+//
+
+extension ISStoreAccount {
+    static var primaryAccountIsPresentAndSignedIn: Bool {
+        return CKAccountStore.sharedAccountStore().primaryAccountIsPresentAndSignedIn
+    }
+    
+    static var primaryAccount: ISStoreAccount? {
+        return CKAccountStore.sharedAccountStore().primaryAccount
+    }
+}

mas-cli/AppStore/StoreAccount.swift

@@ -1,12 +0,0 @@
-//
-//  Account.swift
-//  mas-cli
-//
-//  Created by Andrew Naylor on 22/08/2015.
-//  Copyright (c) 2015 Andrew Naylor. All rights reserved.
-//
-
-func primaryAccount() -> ISStoreAccount {
-    let accountController = CKAccountStore.sharedAccountStore()
-    return accountController.primaryAccount
-}

mas-cli/Commands/Account.swift

@@ -13,7 +13,13 @@ struct AccountCommand: CommandType {
     func run(mode: CommandMode) -> Result<(), CommandantError<MASError>> {
         switch mode {
         case .Arguments:
-            print(primaryAccount().identifier)
+            if let account = ISStoreAccount.primaryAccount {
+                println(account.identifier)
+            }
+            else {
+                println("Not signed in")
+                exit(MASErrorCode.NotSignedIn.exitCode)
+            }
         default:
             break
         }

mas-cli/Error.swift

@@ -6,9 +6,30 @@
 //  Copyright (c) 2015 Andrew Naylor. All rights reserved.
 //
 
-public enum MASError: Equatable {
+public let MASErrorDomain: String = "MASErrorDomain"
-    public var description: String {
+
-        return ""
+private let MASErrorSource: String = "MASErrorSource"
+
+public enum MASErrorCode: Int {
+    case NoError
+    case NotSignedIn
+    
+    var exitCode: Int32 {
+        return Int32(self.rawValue)
+    }
+}
+
+public class MASError: NSError {
+    var masCode: MASErrorCode? {
+        return MASErrorCode(rawValue: code)
+    }
+    
+    convenience init(code: MASErrorCode, sourceError: NSError? = nil) {
+        var userInfo: [NSObject: AnyObject] = [:]
+        if let error = sourceError {
+            userInfo[MASErrorSource] = error
+        }
+        self.init(domain: MASErrorDomain, code: code.rawValue, userInfo: userInfo)
     }
 }