SEBWIN-183: Refactored I18n components and extended their unit tests.

SafeExamBrowser.Configuration/Settings.cs

@@ -29,7 +29,7 @@ namespace SafeExamBrowser.Configuration
 
 		public bool AllowApplicationLog => true;
 		public bool AllowKeyboardLayout => true;
-		public string AppDataFolderName => "SafeExamBrowser";
+		public string AppDataFolderName => nameof(SafeExamBrowser);
 
 		public string ApplicationLogFile
 		{

SafeExamBrowser.Contracts/I18n/IText.cs

@@ -10,9 +10,14 @@ namespace SafeExamBrowser.Contracts.I18n
 {
 	public interface IText
 	{
+		/// <summary>
+		/// Initializes the text module, e.g. loads text data from the specified text resource.
+		/// </summary>
+		void Initialize(ITextResource resource);
+
 		/// <summary>
 		/// Gets the text associated with the specified key. If the key was not found, a default text indicating
-		/// that the given key is not configured shall be returned.
+		/// that the given key is not configured will be returned.
 		/// </summary>
 		string Get(TextKey key);
 	}

SafeExamBrowser.Contracts/I18n/ITextResource.cs

@@ -13,7 +13,7 @@ namespace SafeExamBrowser.Contracts.I18n
 	public interface ITextResource
 	{
 		/// <summary>
-		/// Loads all text data from a resource.
+		/// Loads all text data from a resource. Throws an exception if the data could not be loaded, e.g. due to a data format error.
 		/// </summary>
 		IDictionary<TextKey, string> LoadText();
 	}

SafeExamBrowser.Core.UnitTests/I18n/TextTests.cs

@@ -11,6 +11,7 @@ using System.Collections.Generic;
 using Microsoft.VisualStudio.TestTools.UnitTesting;
 using Moq;
 using SafeExamBrowser.Contracts.I18n;
+using SafeExamBrowser.Contracts.Logging;
 using SafeExamBrowser.Core.I18n;
 
 namespace SafeExamBrowser.Core.UnitTests.I18n
@@ -18,14 +19,18 @@ namespace SafeExamBrowser.Core.UnitTests.I18n
 	[TestClass]
 	public class TextTests
 	{
+		private Mock<ILogger> loggerMock;
+
+		[TestInitialize]
+		public void Initialize()
+		{
+			loggerMock = new Mock<ILogger>();
+		}
+
 		[TestMethod]
 		public void MustNeverReturnNull()
 		{
-			var resource = new Mock<ITextResource>();
+			var sut = new Text(loggerMock.Object);
-			var sut = new Text(resource.Object);
-
-			resource.Setup(r => r.LoadText()).Returns<IDictionary<TextKey, string>>(null);
-
 			var text = sut.Get((TextKey)(-1));
 
 			Assert.IsNotNull(text);
@@ -35,7 +40,39 @@ namespace SafeExamBrowser.Core.UnitTests.I18n
 		[ExpectedException(typeof(ArgumentNullException))]
 		public void MustNotAllowNullResource()
 		{
-			new Text(null);
+			var sut = new Text(loggerMock.Object);
+
+			sut.Initialize(null);
+		}
+
+		[TestMethod]
+		public void MustNotFailWhenGettingNullFromResource()
+		{
+			var resource = new Mock<ITextResource>();
+			var sut = new Text(loggerMock.Object);
+
+			resource.Setup(r => r.LoadText()).Returns<IDictionary<TextKey, string>>(null);
+			sut.Initialize(resource.Object);
+
+			var text = sut.Get((TextKey)(-1));
+
+			Assert.IsNotNull(text);
+		}
+
+		[TestMethod]
+		public void MustNotFailWhenResourceThrowsException()
+		{
+			var resource = new Mock<ITextResource>();
+			var sut = new Text(loggerMock.Object);
+
+			resource.Setup(r => r.LoadText()).Throws<Exception>();
+			sut.Initialize(resource.Object);
+
+			var text = sut.Get((TextKey)(-1));
+
+			loggerMock.Verify(l => l.Error(It.IsAny<string>(), It.IsAny<Exception>()), Times.AtLeastOnce);
+
+			Assert.IsNotNull(text);
 		}
 	}
 }

SafeExamBrowser.Core.UnitTests/I18n/Text_Incompatible.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<Blubb>
+  <ThisTagIsNotSupported>Some random text here...</ThisTagIsNotSupported>
+  <NeitherIsThisOne>Bappa-dee boopa-dee</NeitherIsThisOne>
+  <AnEmptyTag />
+</Blubb>

SafeExamBrowser.Core.UnitTests/I18n/Text_Invalid.txt

@@ -0,0 +1,13 @@
+<?xyzml version="1.0" encoding="utf-8" ?>
+<Blubb>
+  Some random text here
+  <LogWindow_Title\>>
+  <Version *+()=?!
+  <xml>
+    Data
+  </xml>
+</Blubb>
+<Blobb>
+  <Blabb>
+    <Bappa-dee-boopa-dee>/Bappa-dee-boopa-dee>
+  </Blabb>

SafeExamBrowser.Core.UnitTests/I18n/Text_Valid.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<Text>
+  <LogWindow_Title>Application Log</LogWindow_Title>
+  <Version>Version</Version>
+</Text>

SafeExamBrowser.Core.UnitTests/I18n/XmlTextResourceTests.cs

@@ -0,0 +1,75 @@
+/*
+ * Copyright (c) 2017 ETH Zürich, Educational Development and Technology (LET)
+ * 
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+using System;
+using System.IO;
+using System.Reflection;
+using System.Xml;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+using SafeExamBrowser.Contracts.I18n;
+using SafeExamBrowser.Core.I18n;
+
+namespace SafeExamBrowser.Core.UnitTests.I18n
+{
+	[TestClass]
+	public class XmlTextResourceTests
+	{
+		[TestMethod]
+		public void MustCorrectlyLoadData()
+		{
+			var location = Assembly.GetAssembly(typeof(XmlTextResourceTests)).Location;
+			var path = Path.GetDirectoryName(location) + $@"\{nameof(I18n)}\Text_Valid.xml";
+			var sut = new XmlTextResource(path);
+
+			var text = sut.LoadText();
+
+			Assert.IsNotNull(text);
+			Assert.IsTrue(text.Count == 2);
+			Assert.AreEqual("Application Log", text[TextKey.LogWindow_Title]);
+			Assert.AreEqual("Version", text[TextKey.Version]);
+		}
+
+		[TestMethod]
+		[ExpectedException(typeof(XmlException))]
+		public void MustFailWithInvalidData()
+		{
+			var location = Assembly.GetAssembly(typeof(XmlTextResourceTests)).Location;
+			var path = Path.GetDirectoryName(location) + $@"\{nameof(I18n)}\Text_Invalid.txt";
+			var sut = new XmlTextResource(path);
+
+			sut.LoadText();
+		}
+
+		[TestMethod]
+		public void MustNeverReturnNull()
+		{
+			var location = Assembly.GetAssembly(typeof(XmlTextResourceTests)).Location;
+			var path = Path.GetDirectoryName(location) + $@"\{nameof(I18n)}\Text_Incompatible.xml";
+			var sut = new XmlTextResource(path);
+
+			var text = sut.LoadText();
+
+			Assert.IsNotNull(text);
+			Assert.IsTrue(text.Count == 0);
+		}
+
+		[TestMethod]
+		[ExpectedException(typeof(ArgumentException))]
+		public void MustNotAcceptInvalidPath()
+		{
+			new XmlTextResource("This is not a valid path");
+		}
+
+		[TestMethod]
+		[ExpectedException(typeof(ArgumentNullException))]
+		public void MustNotAcceptNullAsPath()
+		{
+			new XmlTextResource(null);
+		}
+	}
+}

SafeExamBrowser.Core.UnitTests/SafeExamBrowser.Core.UnitTests.csproj

@@ -69,12 +69,14 @@
       <HintPath>..\packages\Moq.4.7.63\lib\net45\Moq.dll</HintPath>
     </Reference>
     <Reference Include="System" />
+    <Reference Include="System.Xml" />
   </ItemGroup>
   <ItemGroup>
     <Compile Include="Behaviour\RuntimeControllerTests.cs" />
     <Compile Include="Behaviour\StartupControllerTests.cs" />
     <Compile Include="Behaviour\ShutdownControllerTests.cs" />
     <Compile Include="I18n\TextTests.cs" />
+    <Compile Include="I18n\XmlTextResourceTests.cs" />
     <Compile Include="Logging\LoggerTests.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
   </ItemGroup>
@@ -91,6 +93,17 @@
   <ItemGroup>
     <None Include="packages.config" />
   </ItemGroup>
+  <ItemGroup>
+    <Content Include="I18n\Text_Invalid.txt">
+      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
+    </Content>
+    <Content Include="I18n\Text_Incompatible.xml">
+      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
+    </Content>
+    <Content Include="I18n\Text_Valid.xml">
+      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
+    </Content>
+  </ItemGroup>
   <Import Project="$(VSToolsPath)\TeamTest\Microsoft.TestTools.targets" Condition="Exists('$(VSToolsPath)\TeamTest\Microsoft.TestTools.targets')" />
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
   <Target Name="EnsureNuGetPackageBuildImports" BeforeTargets="PrepareForBuild">

SafeExamBrowser.Core/Behaviour/Operations/I18nOperation.cs

@@ -0,0 +1,49 @@
+/*
+ * Copyright (c) 2017 ETH Zürich, Educational Development and Technology (LET)
+ * 
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+using System.Globalization;
+using System.IO;
+using System.Reflection;
+using SafeExamBrowser.Contracts.Behaviour;
+using SafeExamBrowser.Contracts.I18n;
+using SafeExamBrowser.Contracts.Logging;
+using SafeExamBrowser.Contracts.UserInterface;
+using SafeExamBrowser.Core.I18n;
+
+namespace SafeExamBrowser.Core.Behaviour.Operations
+{
+	public class I18nOperation : IOperation
+	{
+		private ILogger logger;
+		private IText text;
+
+		public ISplashScreen SplashScreen { private get; set; }
+
+		public I18nOperation(ILogger logger, IText text)
+		{
+			this.logger = logger;
+			this.text = text;
+		}
+
+		public void Perform()
+		{
+			logger.Info($"Loading default text data (the currently active culture is '{CultureInfo.CurrentCulture.Name}')...");
+
+			var location = Assembly.GetAssembly(typeof(XmlTextResource)).Location;
+			var path = Path.GetDirectoryName(location) + $@"\{nameof(I18n)}\Text.xml";
+			var textResource = new XmlTextResource(path);
+
+			text.Initialize(textResource);
+		}
+
+		public void Revert()
+		{
+			// Nothing to do here...
+		}
+	}
+}

SafeExamBrowser.Core/Behaviour/RuntimeController.cs

@@ -45,6 +45,7 @@ namespace SafeExamBrowser.Core.Behaviour
 
 		public void Stop()
 		{
+			displayMonitor.DisplayChanged -= DisplayMonitor_DisplaySettingsChanged;
 			processMonitor.ExplorerStarted -= ProcessMonitor_ExplorerStarted;
 			windowMonitor.WindowChanged -= WindowMonitor_WindowChanged;
 		}

SafeExamBrowser.Core/I18n/Text.cs

@@ -9,26 +9,40 @@
 using System;
 using System.Collections.Generic;
 using SafeExamBrowser.Contracts.I18n;
+using SafeExamBrowser.Contracts.Logging;
 
 namespace SafeExamBrowser.Core.I18n
 {
 	public class Text : IText
 	{
-		private readonly IDictionary<TextKey, string> cache;
+		private IDictionary<TextKey, string> cache = new Dictionary<TextKey, string>();
+		private ILogger logger;
 
-		public Text(ITextResource resource)
+		public Text(ILogger logger)
 		{
-			if (resource == null)
+			this.logger = logger;
-			{
-				throw new ArgumentNullException(nameof(resource));
-			}
-
-			cache = resource.LoadText() ?? new Dictionary<TextKey, string>();
 		}
 
 		public string Get(TextKey key)
 		{
 			return cache.ContainsKey(key) ? cache[key] : $"Could not find string for key '{key}'!";
 		}
+
+		public void Initialize(ITextResource resource)
+		{
+			if (resource == null)
+			{
+				throw new ArgumentNullException(nameof(resource));
+			}
+
+			try
+			{
+				cache = resource.LoadText() ?? new Dictionary<TextKey, string>();
+			}
+			catch (Exception e)
+			{
+				logger.Error("Failed to load text data from provided resource!", e);
+			}
+		}
 	}
 }

SafeExamBrowser.Core/I18n/XmlTextResource.cs

@@ -9,7 +9,6 @@
 using System;
 using System.Collections.Generic;
 using System.IO;
-using System.Reflection;
 using System.Xml.Linq;
 using SafeExamBrowser.Contracts.I18n;
 
@@ -17,10 +16,30 @@ namespace SafeExamBrowser.Core.I18n
 {
 	public class XmlTextResource : ITextResource
 	{
+		private string path;
+
+		/// <summary>
+		/// Initializes a new text resource for an XML file located at the specified path.
+		/// </summary>
+		/// <exception cref="System.ArgumentException">If the specifed file does not exist.</exception>
+		/// <exception cref="System.ArgumentNullException">If the given path is null.</exception>
+		public XmlTextResource(string path)
+		{
+			if (path == null)
+			{
+				throw new ArgumentNullException(nameof(path));
+			}
+
+			if (!File.Exists(path))
+			{
+				throw new ArgumentException("The specified file does not exist!");
+			}
+
+			this.path = path;
+		}
+
 		public IDictionary<TextKey, string> LoadText()
 		{
-			var assembly = Assembly.GetAssembly(typeof(XmlTextResource)).Location;
-			var path = Path.GetDirectoryName(assembly) + $@"\{nameof(I18n)}\Text.xml";
 			var xml = XDocument.Load(path);
 			var text = new Dictionary<TextKey, string>();
 

SafeExamBrowser.Core/SafeExamBrowser.Core.csproj

@@ -55,6 +55,7 @@
   </ItemGroup>
   <ItemGroup>
     <Compile Include="Behaviour\Operations\ClipboardOperation.cs" />
+    <Compile Include="Behaviour\Operations\I18nOperation.cs" />
     <Compile Include="Behaviour\Operations\KeyboardInterceptorOperation.cs" />
     <Compile Include="Behaviour\Operations\MouseInterceptorOperation.cs" />
     <Compile Include="Behaviour\RuntimeController.cs" />

SafeExamBrowser.UserInterface.Classic/SplashScreen.xaml.cs

@@ -73,7 +73,7 @@ namespace SafeExamBrowser.UserInterface.Classic
 
 		private void InitializeSplashScreen()
 		{
-			InfoTextBlock.Inlines.Add(new Run($"{text.Get(TextKey.Version)} {settings.ProgramVersion}") { FontStyle = FontStyles.Italic });
+			InfoTextBlock.Inlines.Add(new Run($"Version {settings.ProgramVersion}") { FontStyle = FontStyles.Italic });
 			InfoTextBlock.Inlines.Add(new LineBreak());
 			InfoTextBlock.Inlines.Add(new LineBreak());
 			InfoTextBlock.Inlines.Add(new Run(settings.ProgramCopyright) { FontSize = 10 });

SafeExamBrowser.UserInterface.Windows10/SplashScreen.xaml.cs

@@ -73,7 +73,7 @@ namespace SafeExamBrowser.UserInterface.Windows10
 
 		private void InitializeSplashScreen()
 		{
-			InfoTextBlock.Inlines.Add(new Run($"{text.Get(TextKey.Version)} {settings.ProgramVersion}") { FontStyle = FontStyles.Italic });
+			InfoTextBlock.Inlines.Add(new Run($"Version {settings.ProgramVersion}") { FontStyle = FontStyles.Italic });
 			InfoTextBlock.Inlines.Add(new LineBreak());
 			InfoTextBlock.Inlines.Add(new LineBreak());
 			InfoTextBlock.Inlines.Add(new Run(settings.ProgramCopyright) { FontSize = 10 });

SafeExamBrowser/CompositionRoot.cs

@@ -51,7 +51,6 @@ namespace SafeExamBrowser
 		private ISystemComponent<ISystemPowerSupplyControl> powerSupply;
 		private ISystemInfo systemInfo;
 		private IText text;
-		private ITextResource textResource;
 		private IUserInterfaceFactory uiFactory;
 		private IWindowMonitor windowMonitor;
 
@@ -68,12 +67,11 @@ namespace SafeExamBrowser
 			nativeMethods = new NativeMethods();
 			settings = new Settings();
 			systemInfo = new SystemInfo();
-			textResource = new XmlTextResource();
 			uiFactory = new UserInterfaceFactory();
 
 			logger.Subscribe(new LogFileWriter(logFormatter, settings));
 
-			text = new Text(textResource);
+			text = new Text(logger);
 			Taskbar = new Taskbar(new ModuleLogger(logger, typeof(Taskbar)));
 			browserController = new BrowserApplicationController(settings, text, uiFactory);
 			displayMonitor = new DisplayMonitor(new ModuleLogger(logger, typeof(DisplayMonitor)), nativeMethods);
@@ -89,6 +87,7 @@ namespace SafeExamBrowser
 			StartupController = new StartupController(logger, settings, systemInfo, text, uiFactory);
 
 			StartupOperations = new Queue<IOperation>();
+			StartupOperations.Enqueue(new I18nOperation(logger, text));
 			StartupOperations.Enqueue(new KeyboardInterceptorOperation(keyboardInterceptor, logger, nativeMethods));
 			StartupOperations.Enqueue(new WindowMonitorOperation(logger, windowMonitor));
 			StartupOperations.Enqueue(new ProcessMonitorOperation(logger, processMonitor));