Enable nullables on CoreUtilities

src/Microsoft.TestPlatform.CoreUtilities/Constants.cs

@@ -1,8 +1,6 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT license. See LICENSE file in the project root for full license information.
 
-#nullable disable
-
 namespace Microsoft.VisualStudio.TestPlatform.CoreUtilities;
 
 /// <summary>

src/Microsoft.TestPlatform.CoreUtilities/Extensions/StringBuilderExtensions.cs

@@ -4,8 +4,6 @@
 using System;
 using System.Text;
 
-#nullable disable
-
 namespace Microsoft.VisualStudio.TestPlatform.CoreUtilities.Extensions;
 
 public static class StringBuilderExtensions
@@ -16,26 +14,28 @@ public static class StringBuilderExtensions
     /// <param name="result">string builder</param>
     /// <param name="data">data to be appended.</param>
     /// <returns></returns>
-    public static void AppendSafeWithNewLine(this StringBuilder result, string data)
+    public static void AppendSafeWithNewLine(this StringBuilder result, string? data)
     {
-        if (!string.IsNullOrEmpty(data))
+        if (data.IsNullOrEmpty())
         {
-            // Don't append more data if already reached max length.
-            if (result.Length >= result.MaxCapacity)
-            {
-                return;
-            }
+            return;
+        }
 
-            // Add newline for readability.
-            data += Environment.NewLine;
+        // Don't append more data if already reached max length.
+        if (result.Length >= result.MaxCapacity)
+        {
+            return;
+        }
 
-            // Append sub string of data if appending all the data exceeds max capacity.
-            if (result.Length + data.Length >= result.MaxCapacity)
-            {
-                data = data.Substring(0, result.MaxCapacity - result.Length);
-            }
+        // Add newline for readability.
+        data += Environment.NewLine;
 
-            result.Append(data);
+        // Append sub string of data if appending all the data exceeds max capacity.
+        if (result.Length + data.Length >= result.MaxCapacity)
+        {
+            data = data.Substring(0, result.MaxCapacity - result.Length);
         }
+
+        result.Append(data);
     }
 }

src/Microsoft.TestPlatform.CoreUtilities/Extensions/StringExtensions.cs

@@ -1,8 +1,6 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT license. See LICENSE file in the project root for full license information.
 
-#nullable disable
-
 namespace Microsoft.VisualStudio.TestPlatform.CoreUtilities.Extensions;
 
 public static class StringExtensions

src/Microsoft.TestPlatform.CoreUtilities/FeatureFlag/FeatureFlag.cs

@@ -10,9 +10,9 @@ namespace Microsoft.VisualStudio.TestPlatform.Utilities;
 
 /// <summary>
 /// !!!NEVER USE A FLAG TO ENABLE FUNCTIONALITY!!!
-/// 
+///
 /// The reasoning is:
-/// 
+///
 /// * New version will automatically ship with the feature enabled. There is no action needed to be done just before release.
 /// * Anyone interested in the new feature will get it automatically by grabbing our preview.
 /// * Anyone who needs more time before using the new feature can disable it in the released package.

src/Microsoft.TestPlatform.CoreUtilities/Helpers/CommandLineArgumentsHelper.cs

@@ -4,8 +4,6 @@
 using System;
 using System.Collections.Generic;
 
-#nullable disable
-
 namespace Microsoft.VisualStudio.TestPlatform.CoreUtilities.Helpers;
 
 /// <summary>
@@ -18,9 +16,9 @@ public class CommandLineArgumentsHelper
     /// </summary>
     /// <param name="args">Command line arguments. Ex: <c>{ "--port", "12312", "--parentprocessid", "2312", "--testsourcepath", "C:\temp\1.dll" }</c></param>
     /// <returns>Dictionary of arguments keys and values.</returns>
-    public static IDictionary<string, string> GetArgumentsDictionary(string[] args)
+    public static IDictionary<string, string?> GetArgumentsDictionary(string[]? args)
     {
-        var argsDictionary = new Dictionary<string, string>();
+        var argsDictionary = new Dictionary<string, string?>();
         if (args == null)
         {
             return argsDictionary;
@@ -52,7 +50,7 @@ public static IDictionary<string, string> GetArgumentsDictionary(string[] args)
     /// <param name="fullname">The full name for required argument. Ex: "--port"</param>
     /// <returns>Value of the argument.</returns>
     /// <exception cref="ArgumentException">Thrown if value of an argument is not an integer.</exception>
-    public static int GetIntArgFromDict(IDictionary<string, string> argsDictionary, string fullname)
+    public static int GetIntArgFromDict(IDictionary<string, string?> argsDictionary, string fullname)
     {
         var found = TryGetIntArgFromDict(argsDictionary, fullname, out var value);
         return found ? value : 0;
@@ -65,7 +63,7 @@ public static int GetIntArgFromDict(IDictionary<string, string> argsDictionary,
     /// <param name="fullname">The full name for required argument. Ex: "--port"</param>
     /// <returns>Value of the argument.</returns>
     /// <exception cref="ArgumentException">Thrown if value of an argument is not an integer.</exception>
-    public static bool TryGetIntArgFromDict(IDictionary<string, string> argsDictionary, string fullname, out int value)
+    public static bool TryGetIntArgFromDict(IDictionary<string, string?> argsDictionary, string fullname, out int value)
     {
         var found = argsDictionary.TryGetValue(fullname, out var optionValue);
         if (!found)
@@ -86,7 +84,7 @@ public static bool TryGetIntArgFromDict(IDictionary<string, string> argsDictiona
     /// <param name="fullname">The full name for required argument. Ex: "--port"</param>
     /// <returns>Value of the argument.</returns>
     /// <exception cref="ArgumentException">Thrown if value of an argument is not an integer.</exception>
-    public static string GetStringArgFromDict(IDictionary<string, string> argsDictionary, string fullname)
+    public static string? GetStringArgFromDict(IDictionary<string, string?> argsDictionary, string fullname)
     {
         return argsDictionary.TryGetValue(fullname, out var optionValue) ? optionValue : string.Empty;
     }

src/Microsoft.TestPlatform.CoreUtilities/Helpers/DotnetHostHelper.cs

@@ -4,6 +4,7 @@
 #if !NETSTANDARD1_0
 
 using System;
+using System.Diagnostics.CodeAnalysis;
 using System.IO;
 using System.Reflection.PortableExecutable;
 
@@ -17,8 +18,6 @@
 using Microsoft.VisualStudio.TestPlatform.Utilities.Helpers.Interfaces;
 using Microsoft.Win32;
 
-#nullable disable
-
 namespace Microsoft.VisualStudio.TestPlatform.CrossPlatEngine.Helpers;
 
 public class DotnetHostHelper : IDotnetHostHelper
@@ -120,12 +119,12 @@ private bool TryGetExecutablePath(string executableBaseName, out string executab
         return false;
     }
 
-    public bool TryGetDotnetPathByArchitecture(PlatformArchitecture targetArchitecture, out string muxerPath)
+    public bool TryGetDotnetPathByArchitecture(PlatformArchitecture targetArchitecture, [NotNullWhen(true)] out string? muxerPath)
     {
         // If current process is the same as the target architecture we return the current process filename.
         if (_processHelper.GetCurrentProcessArchitecture() == targetArchitecture)
         {
-            string currentProcessFileName = _processHelper.GetCurrentProcessFileName();
+            string currentProcessFileName = _processHelper.GetCurrentProcessFileName()!;
             if (Path.GetFileName(currentProcessFileName) == _muxerName)
             {
                 muxerPath = currentProcessFileName;
@@ -279,48 +278,40 @@ public bool TryGetDotnetPathByArchitecture(PlatformArchitecture targetArchitectu
         return true;
     }
 
-    private string GetMuxerFromGlobalRegistrationWin(PlatformArchitecture targetArchitecture)
+    private string? GetMuxerFromGlobalRegistrationWin(PlatformArchitecture targetArchitecture)
     {
         // Installed version are always in 32-bit view of registry
         // https://github.com/dotnet/designs/blob/main/accepted/2020/install-locations.md#globally-registered-install-location-new
         // "Note that this registry key is "redirected" that means that 32-bit processes see different copy of the key than 64bit processes.
         // So it's important that both installers and the host access only the 32-bit view of the registry."
-        using (IRegistryKey hklm = _windowsRegistryHelper.OpenBaseKey(RegistryHive.LocalMachine, RegistryView.Registry32))
+        using IRegistryKey? hklm = _windowsRegistryHelper.OpenBaseKey(RegistryHive.LocalMachine, RegistryView.Registry32);
+        if (hklm == null)
         {
-            if (hklm != null)
-            {
-                using IRegistryKey dotnetInstalledVersion = hklm.OpenSubKey(@"SOFTWARE\dotnet\Setup\InstalledVersions");
-                if (dotnetInstalledVersion != null)
-                {
-                    using IRegistryKey nativeArch = dotnetInstalledVersion.OpenSubKey(targetArchitecture.ToString().ToLowerInvariant());
-                    string installLocation = nativeArch?.GetValue("InstallLocation")?.ToString();
-
-                    if (installLocation != null)
-                    {
-                        string path = Path.Combine(installLocation.Trim(), _muxerName);
-                        EqtTrace.Verbose($@"DotnetHostHelper.GetMuxerFromGlobalRegistrationWin: Muxer resolved using win registry key 'SOFTWARE\dotnet\Setup\InstalledVersions\{targetArchitecture.ToString().ToLowerInvariant()}\InstallLocation' in '{path}'");
-                        return path;
-                    }
-                    else
-                    {
-                        EqtTrace.Verbose($@"DotnetHostHelper.GetMuxerFromGlobalRegistrationWin: Missing registry InstallLocation");
-                    }
-                }
-                else
-                {
-                    EqtTrace.Verbose($@"DotnetHostHelper.GetMuxerFromGlobalRegistrationWin: Missing RegistryHive.LocalMachine for RegistryView.Registry32");
-                }
-            }
-            else
-            {
-                EqtTrace.Verbose($@"DotnetHostHelper.GetMuxerFromGlobalRegistrationWin: Missing SOFTWARE\dotnet\Setup\InstalledVersions subkey");
-            }
+            EqtTrace.Verbose($@"DotnetHostHelper.GetMuxerFromGlobalRegistrationWin: Missing SOFTWARE\dotnet\Setup\InstalledVersions subkey");
+            return null;
         }
 
-        return null;
+        using IRegistryKey? dotnetInstalledVersion = hklm.OpenSubKey(@"SOFTWARE\dotnet\Setup\InstalledVersions");
+        if (dotnetInstalledVersion == null)
+        {
+            EqtTrace.Verbose($@"DotnetHostHelper.GetMuxerFromGlobalRegistrationWin: Missing RegistryHive.LocalMachine for RegistryView.Registry32");
+            return null;
+        }
+
+        using IRegistryKey? nativeArch = dotnetInstalledVersion.OpenSubKey(targetArchitecture.ToString().ToLowerInvariant());
+        string? installLocation = nativeArch?.GetValue("InstallLocation")?.ToString();
+        if (installLocation == null)
+        {
+            EqtTrace.Verbose($@"DotnetHostHelper.GetMuxerFromGlobalRegistrationWin: Missing registry InstallLocation");
+            return null;
+        }
+
+        string path = Path.Combine(installLocation.Trim(), _muxerName);
+        EqtTrace.Verbose($@"DotnetHostHelper.GetMuxerFromGlobalRegistrationWin: Muxer resolved using win registry key 'SOFTWARE\dotnet\Setup\InstalledVersions\{targetArchitecture.ToString().ToLowerInvariant()}\InstallLocation' in '{path}'");
+        return path;
     }
 
-    private string GetMuxerFromGlobalRegistrationOnUnix(PlatformArchitecture targetArchitecture)
+    private string? GetMuxerFromGlobalRegistrationOnUnix(PlatformArchitecture targetArchitecture)
     {
         string baseInstallLocation = "/etc/dotnet/";
 
@@ -333,22 +324,24 @@ private string GetMuxerFromGlobalRegistrationOnUnix(PlatformArchitecture targetA
             installLocation = $"{baseInstallLocation}install_location";
         }
 
-        if (_fileHelper.Exists(installLocation))
+        if (!_fileHelper.Exists(installLocation))
         {
-            try
-            {
-                using Stream stream = _fileHelper.GetStream(installLocation, FileMode.Open, FileAccess.Read);
-                using StreamReader streamReader = new(stream);
-                string content = streamReader.ReadToEnd().Trim();
-                EqtTrace.Verbose($"DotnetHostHelper: '{installLocation}' content '{content}'");
-                string path = Path.Combine(content, _muxerName);
-                EqtTrace.Verbose($"DotnetHostHelper: Muxer resolved using '{installLocation}' in '{path}'");
-                return path;
-            }
-            catch (Exception ex)
-            {
-                EqtTrace.Error($"DotnetHostHelper.GetMuxerFromGlobalRegistrationOnUnix: Exception during '{installLocation}' muxer resolution.\n{ex}");
-            }
+            return null;
+        }
+
+        try
+        {
+            using Stream stream = _fileHelper.GetStream(installLocation, FileMode.Open, FileAccess.Read);
+            using StreamReader streamReader = new(stream);
+            string content = streamReader.ReadToEnd().Trim();
+            EqtTrace.Verbose($"DotnetHostHelper: '{installLocation}' content '{content}'");
+            string path = Path.Combine(content, _muxerName);
+            EqtTrace.Verbose($"DotnetHostHelper: Muxer resolved using '{installLocation}' in '{path}'");
+            return path;
+        }
+        catch (Exception ex)
+        {
+            EqtTrace.Error($"DotnetHostHelper.GetMuxerFromGlobalRegistrationOnUnix: Exception during '{installLocation}' muxer resolution.\n{ex}");
         }
 
         return null;

src/Microsoft.TestPlatform.CoreUtilities/Helpers/EnvironmentHelper.cs

@@ -7,8 +7,6 @@
 
 using Microsoft.VisualStudio.TestPlatform.ObjectModel;
 
-#nullable disable
-
 namespace Microsoft.VisualStudio.TestPlatform.CoreUtilities.Helpers;
 
 public class EnvironmentHelper
@@ -28,7 +26,7 @@ public static int GetConnectionTimeout()
         var envVarValue = Environment.GetEnvironmentVariable(VstestConnectionTimeout);
 #endif
 
-        if (!string.IsNullOrEmpty(envVarValue) && int.TryParse(envVarValue, out int value) && value >= 0)
+        if (!envVarValue.IsNullOrEmpty() && int.TryParse(envVarValue, out int value) && value >= 0)
         {
             EqtTrace.Info("EnvironmentHelper.GetConnectionTimeout: {0} value set to {1}.", VstestConnectionTimeout, value);
         }

src/Microsoft.TestPlatform.CoreUtilities/Helpers/EnvironmentVariableHelper.cs

@@ -7,8 +7,6 @@
 
 using Microsoft.VisualStudio.TestPlatform.Utilities.Helpers.Interfaces;
 
-#nullable disable
-
 namespace Microsoft.VisualStudio.TestPlatform.CoreUtilities.Helpers;
 
 internal class EnvironmentVariableHelper : IEnvironmentVariableHelper

src/Microsoft.TestPlatform.CoreUtilities/Helpers/FileHelper.cs

@@ -11,8 +11,6 @@
 
 using Microsoft.VisualStudio.TestPlatform.Utilities.Helpers.Interfaces;
 
-#nullable disable
-
 namespace Microsoft.VisualStudio.TestPlatform.Utilities.Helpers;
 
 /// <summary>

src/Microsoft.TestPlatform.CoreUtilities/Helpers/Interfaces/IWindowsRegistryHelper.cs

@@ -7,22 +7,20 @@
 
 using Microsoft.Win32;
 
-#nullable disable
-
 namespace Microsoft.VisualStudio.TestPlatform.Utilities.Helpers.Interfaces;
 
 internal interface IWindowsRegistryHelper
 {
-    IRegistryKey OpenBaseKey(RegistryHive hKey, RegistryView view);
+    IRegistryKey? OpenBaseKey(RegistryHive hKey, RegistryView view);
 }
 
 internal interface IRegistryKey : IDisposable
 {
-    IRegistryKey OpenSubKey(string name);
+    IRegistryKey? OpenSubKey(string name);
 
-    object GetValue(string name);
+    object? GetValue(string name);
 
-    string[] GetSubKeyNames();
+    string[]? GetSubKeyNames();
 }
 
 #endif

src/Microsoft.TestPlatform.CoreUtilities/Helpers/RunSettingsHelper.cs

@@ -3,8 +3,6 @@
 
 using Microsoft.VisualStudio.TestPlatform.Utilities.Helpers.Interfaces;
 
-#nullable disable
-
 namespace Microsoft.VisualStudio.TestPlatform.Utilities.Helpers;
 
 /// <summary>

src/Microsoft.TestPlatform.CoreUtilities/Helpers/WindowsRegistryHelper.cs

@@ -7,13 +7,11 @@
 
 using Microsoft.Win32;
 
-#nullable disable
-
 namespace Microsoft.VisualStudio.TestPlatform.Utilities.Helpers;
 
 internal class WindowsRegistryHelper : IWindowsRegistryHelper
 {
-    public IRegistryKey OpenBaseKey(RegistryHive hKey, RegistryView view)
+    public IRegistryKey? OpenBaseKey(RegistryHive hKey, RegistryView view)
     {
         var keyRegistry = RegistryKey.OpenBaseKey(hKey, view);
         return keyRegistry is null ? null : new RegistryKeyWrapper(keyRegistry);
@@ -29,18 +27,18 @@ public RegistryKeyWrapper(RegistryKey registryKey)
         _registryKey = registryKey;
     }
 
-    public object GetValue(string name)
+    public object? GetValue(string name)
     {
         return _registryKey?.GetValue(name)?.ToString();
     }
 
-    public IRegistryKey OpenSubKey(string name)
+    public IRegistryKey? OpenSubKey(string name)
     {
         var keyRegistry = _registryKey.OpenSubKey(name);
         return keyRegistry is null ? null : new RegistryKeyWrapper(keyRegistry);
     }
 
-    public string[] GetSubKeyNames()
+    public string[]? GetSubKeyNames()
         => _registryKey?.GetSubKeyNames();
 
     public void Dispose()