Introduce KeyStore protocol in order to provide specialized key store implementations for tests

With the DictBasedKeychain the main AppKeychain is not influenced by tests. The previous implementation led to an empty Keychain requiring a new setup of the simulator.

passKitTests/Models/PGPAgentTest.swift

@@ -11,14 +11,8 @@ import XCTest
 @testable import passKit
 
 class PGPAgentTest: XCTestCase {
-    
-    override func setUp() {
-        PGPAgent().removePGPKeys()
-    }
-    
-    override func tearDown() {
-        PGPAgent().removePGPKeys()
-    }
+
+    private let keychain = DictBasedKeychain()
     
     func basicEncryptDecrypt(pgpAgent: PGPAgent) -> Bool {
         // Encrypt and decrypt.
@@ -33,7 +27,7 @@ class PGPAgentTest: XCTestCase {
     }
     
     func testInitPGPKey() {
-        let pgpAgent = PGPAgent()
+        let pgpAgent = PGPAgent(keyStore: keychain)
 
         // [RSA2048] Setup keys.
         try? pgpAgent.initPGPKey(with: PGP_RSA2048_PUBLIC_KEY, keyType: .PUBLIC)
@@ -41,7 +35,7 @@ class PGPAgentTest: XCTestCase {
         XCTAssertTrue(pgpAgent.isImported)
         XCTAssertEqual(pgpAgent.pgpKeyID, "A1024DAE")
         XCTAssertTrue(self.basicEncryptDecrypt(pgpAgent: pgpAgent))
-        let pgpAgent2 = PGPAgent()
+        let pgpAgent2 = PGPAgent(keyStore: keychain)
         try? pgpAgent2.initPGPKeys()  // load from the keychain
         XCTAssertTrue(self.basicEncryptDecrypt(pgpAgent: pgpAgent2))
         pgpAgent.removePGPKeys()
@@ -88,7 +82,7 @@ class PGPAgentTest: XCTestCase {
     }
     
     func testInitPGPKeyBadPrivateKeys() {
-        let pgpAgent = PGPAgent()
+        let pgpAgent = PGPAgent(keyStore: keychain)
         let plainData = "Hello World!".data(using: .utf8)!
         
         // [RSA2048] Setup the public key.

passKitTests/Testbase/DictBasedKeychain.swift

@@ -0,0 +1,42 @@
+//
+//  DictBasedKeychain.swift
+//  passKitTests
+//
+//  Created by Danny Moesch on 20.07.19.
+//  Copyright © 2019 Bob Sun. All rights reserved.
+//
+
+import Foundation
+import passKit
+
+class DictBasedKeychain: KeyStore {
+    private var store: [String: Any] = [:]
+
+    public func add(data: Data?, for key: String) {
+        store[key] = data
+    }
+
+    public func add(string: String?, for key: String) {
+        store[key] = string
+    }
+
+    public func contains(key: String) -> Bool {
+        return store[key] != nil
+    }
+
+    public func get(for key: String) -> Data? {
+        return store[key] as? Data
+    }
+
+    public func get(for key: String) -> String? {
+        return store[key] as? String
+    }
+
+    public func removeContent(for key: String) {
+        store.removeValue(forKey: key)
+    }
+
+    public func removeAllContent() {
+        store.removeAll()
+    }
+}