Use Microsoft.IO over System.IO

Directory.Build.props

@@ -143,6 +143,10 @@
     <Using Include="Microsoft.VisualStudio.Composition.ImportCardinality" Alias="ImportCardinality" />
     <!-- Prevent accidental use of Microsoft.VisualStudio.Threading.IAsyncDisposable -->
     <Using Include="System.IAsyncDisposable" Alias="IAsyncDisposable" />
+    <!-- Enforce use of Microsoft.IO -->
+    <Using Include="Microsoft.IO.Path" Alias="Path" Condition="'$(TargetFrameworkIdentifier)' == '.NETFramework'" />
+    <Using Include="Microsoft.IO.Directory" Alias="Directory" Condition="'$(TargetFrameworkIdentifier)' == '.NETFramework'" />
+    <Using Include="Microsoft.IO.SearchOption" Alias="SearchOption" Condition="'$(TargetFrameworkIdentifier)' == '.NETFramework'" />
   </ItemGroup>
 
   <Import Project="eng\imports\LanguageSettings.props" />

src/Microsoft.VisualStudio.ProjectSystem.Managed.VS/IO/WindowsFileExplorer.cs

@@ -1,7 +1,6 @@
 // Licensed to the .NET Foundation under one or more agreements. The .NET Foundation licenses this file to you under the MIT license. See the LICENSE.md file in the project root for more information.
 
 using System.Runtime.InteropServices;
-using Path = Microsoft.IO.Path;
 
 namespace Microsoft.VisualStudio.IO;
 

src/Microsoft.VisualStudio.ProjectSystem.Managed.VS/ProjectSystem/VS/CreateFileFromTemplateService.cs

@@ -35,12 +35,20 @@ public async Task<bool> CreateFileAsync(string templateFile, string path)
         Requires.NotNull(templateFile);
         Requires.NotNullOrEmpty(path);
 
-        string directoryName = Path.GetDirectoryName(path);
         string fileName = Path.GetFileName(path);
+        string? directoryName = Path.GetDirectoryName(path);
+
+        if (directoryName is null)
+        {
+            return false;
+        }
 
         string? templateLanguage = await GetTemplateLanguageAsync();
+
         if (string.IsNullOrEmpty(templateLanguage))
+        {
             return false;
+        }
 
         await _projectVsServices.ThreadingService.SwitchToUIThread();
 

src/Microsoft.VisualStudio.ProjectSystem.Managed.VS/ProjectSystem/VS/LanguageServices/Handlers/CompileItemHandler.cs

@@ -43,7 +43,7 @@ IEnumerable<string> GetFilePaths(BuildOptions options)
 
     protected override void AddToContext(IWorkspaceProjectContext context, string fullPath, IImmutableDictionary<string, string> metadata, bool isActiveContext, IManagedProjectDiagnosticOutputService logger)
     {
-        string[]? folderNames = FileItemServices.GetLogicalFolderNames(Path.GetDirectoryName(Project.FullPath), fullPath, metadata);
+        string[]? folderNames = FileItemServices.GetLogicalFolderNames(Path.GetDirectoryName(Project.FullPath)!, fullPath, metadata);
 
         logger.WriteLine("Adding source file '{0}'", fullPath);
         context.AddSourceFile(fullPath, isInCurrentContext: isActiveContext, folderNames: folderNames);

src/Microsoft.VisualStudio.ProjectSystem.Managed.VS/ProjectSystem/VS/Rename/FileMoveNotificationListener.cs

@@ -11,7 +11,6 @@
 using Microsoft.VisualStudio.Threading;
 // Debug collides with Microsoft.VisualStudio.ProjectSystem.VS.Debug
 using DiagDebug = System.Diagnostics.Debug;
-using Path = System.IO.Path;
 using static Microsoft.CodeAnalysis.Rename.Renamer;
 
 namespace Microsoft.VisualStudio.ProjectSystem.VS.Rename;
@@ -75,7 +74,13 @@ public async Task OnBeforeFilesMovedAsync(IReadOnlyCollection<IFileMoveItem> ite
             }
 
             // Get the relative folder path from the project to the destination.
-            string destinationFolderPath = Path.GetDirectoryName(_unconfiguredProject.MakeRelative(itemToMove.Destination));
+            string? destinationFolderPath = Path.GetDirectoryName(_unconfiguredProject.MakeRelative(itemToMove.Destination));
+
+            if ( (destinationFolderPath is null))
+            {
+                continue;
+            }
+
             string[] destinationFolders = destinationFolderPath.Split(Delimiter.Path, StringSplitOptions.RemoveEmptyEntries);
 
             // Since this rename only moves the location of the file to another directory, it will use the SyncNamespaceDocumentAction in Roslyn as the rename action within this set.

src/Microsoft.VisualStudio.ProjectSystem.Managed.VS/ProjectSystem/VS/Rename/RenamerProjectTreeActionHandler.cs

@@ -78,13 +78,14 @@ public override async Task RenameAsync(IProjectTreeActionHandlerContext context,
         Requires.NotNullOrEmpty(value);
 
         string? oldFilePath = node.FilePath;
-        string oldName = Path.GetFileNameWithoutExtension(oldFilePath);
+        string? oldName = Path.GetFileNameWithoutExtension(oldFilePath);
         string newFileWithExtension = value;
         CodeAnalysis.Project? project = GetCurrentProject();
 
         await CpsFileRenameAsync(context, node, value);
 
-        if (project is null ||
+        if (oldName is null ||
+            project is null ||
             await IsAutomationFunctionAsync() ||
             node.IsFolder ||
             _vsOnlineServices.ConnectedToVSOnline ||

src/Microsoft.VisualStudio.ProjectSystem.Managed.VS/ProjectSystem/VS/Retargeting/DotNetReleasesProvider.cs

@@ -4,7 +4,6 @@
 using Microsoft.VisualStudio.Linq;
 using Microsoft.VisualStudio.Shell.Interop;
 using Microsoft.VisualStudio.Threading;
-using Path = Microsoft.IO.Path;
 
 namespace Microsoft.VisualStudio.ProjectSystem.VS.Retargeting;
 

src/Microsoft.VisualStudio.ProjectSystem.Managed.VS/ProjectSystem/VS/Retargeting/ProjectRetargetHandler.cs

@@ -6,7 +6,6 @@
 using Microsoft.VisualStudio.Shell.Interop;
 using Microsoft.VisualStudio.Threading;
 using IFileSystem = Microsoft.VisualStudio.IO.IFileSystem;
-using Path = Microsoft.IO.Path;
 
 namespace Microsoft.VisualStudio.ProjectSystem.VS.Retargeting;
 

src/Microsoft.VisualStudio.ProjectSystem.Managed.VS/ProjectSystem/VS/Setup/DotNetEnvironment.cs

@@ -69,7 +69,7 @@ public bool IsSdkInstalled(string sdkVersion)
             registryKey,
             "InstallLocation");
 
-        if (!string.IsNullOrEmpty(installLocation))
+        if (!Strings.IsNullOrEmpty(installLocation))
         {
             string dotnetExePath = Path.Combine(installLocation, "dotnet.exe");
             if (_fileSystem.FileExists(dotnetExePath))

src/Microsoft.VisualStudio.ProjectSystem.Managed.VS/ProjectSystem/VS/TempPE/DesignTimeInputsChangeTracker.cs

@@ -196,6 +196,12 @@ internal void ProcessDataflowChanges(IProjectVersionedValue<ValueTuple<DesignTim
         // Make sure we have the up to date output path. If either of these don't exist, they will be null and we'll handle the ArgumentException below
         string? basePath = configChanges.After.Properties.GetValueOrDefault(ConfigurationGeneral.ProjectDirProperty);
         string? objPath = configChanges.After.Properties.GetValueOrDefault(ConfigurationGeneral.IntermediateOutputPathProperty);
+
+        if (basePath is null || objPath is null)
+        {
+            return null;
+        }
+
         try
         {
             tempPEOutputPath = Path.Combine(basePath, objPath, "TempPE");

src/Microsoft.VisualStudio.ProjectSystem.Managed.VS/ProjectSystem/VS/Tree/Dependencies/AttachedCollections/Implementation/FrameworkReferenceAssemblyItem.cs

@@ -41,7 +41,7 @@ public FrameworkReferenceAssemblyItem(string assemblyName, string? path, string?
     string? IObjectBrowserItem.AssemblyPath => GetAssemblyPath();
 
     private string? GetAssemblyPath() => Path is not null
-        ? System.IO.Path.GetFullPath(System.IO.Path.Combine(Framework.Path, Path))
+        ? Microsoft.IO.Path.GetFullPath(Microsoft.IO.Path.Combine(Framework.Path, Path))
         : null;
 
     private sealed class BrowseObject(FrameworkReferenceAssemblyItem item) : LocalizableProperties

src/Microsoft.VisualStudio.ProjectSystem.Managed.VS/ProjectSystem/VS/UpToDate/BuildUpToDateCheck.FileSystemOperationAggregator.cs

@@ -169,7 +169,7 @@ public void AddCopy(string source, string destination)
                             if (destinationInfo is null)
                             {
                                 // Ensure the destination directory actually exists on disk
-                                _fileSystem.CreateDirectory(Path.GetDirectoryName(destination));
+                                _fileSystem.CreateDirectory(Path.GetDirectoryName(destination)!);
                             }
 
                             // TODO add retry logic in case of failed copies? MSBuild does this with CopyRetryCount and CopyRetryDelayMilliseconds

src/Microsoft.VisualStudio.ProjectSystem.Managed.VS/ProjectSystem/VS/UpToDate/BuildUpToDateCheck.cs

@@ -722,7 +722,7 @@ private bool CheckCopyToOutputDirectoryItems(Log log, UpToDateCheckImplicitConfi
     {
         ITimestampCache timestampCache = solutionBuildContext.CopyItemTimestamps;
 
-        string outputFullPath = Path.Combine(state.MSBuildProjectDirectory, state.OutputRelativeOrFullPath);
+        string outputFullPath = Path.Combine(state.MSBuildProjectDirectory!, state.OutputRelativeOrFullPath!);
 
         Log.Scope? scope1 = null;
 
@@ -1074,7 +1074,7 @@ private async Task<bool> IsUpToDateInternalAsync(
 
                     var configuredFileSystemOperations = new ConfiguredFileSystemOperationAggregator(fileSystemOperations, isBuildAccelerationEnabled, copyInfo.TargetsWithoutReferenceAssemblies);
 
-                    string outputFullPath = Path.Combine(implicitState.MSBuildProjectDirectory, implicitState.OutputRelativeOrFullPath);
+                    string outputFullPath = Path.Combine(implicitState.MSBuildProjectDirectory!, implicitState.OutputRelativeOrFullPath!);
 
                     copyItemPaths.UnionWith(implicitState.ProjectCopyData.CopyItems.Select(copyItem => Path.Combine(outputFullPath, copyItem.RelativeTargetPath)));
 

src/Microsoft.VisualStudio.ProjectSystem.Managed/ProjectSystem/Debug/LaunchSettingsProvider.cs

@@ -563,7 +563,9 @@ protected async Task EnsureSettingsFolderAsync()
     {
         string fileName = await GetLaunchSettingsFilePathAsync();
 
-        string parentPath = Path.GetDirectoryName(fileName);
+        string? parentPath = Path.GetDirectoryName(fileName);
+
+        Assumes.NotNull(parentPath);
 
         _fileSystem.CreateDirectory(parentPath);
     }

src/Microsoft.VisualStudio.ProjectSystem.Managed/ProjectSystem/ProjectTreeProviderExtensions.cs

@@ -40,7 +40,12 @@ internal static class ProjectTreeProviderExtensions
 
         string? projectFilePath = provider.GetPath(target.Root);
 
-        string rootPath = Path.GetDirectoryName(projectFilePath);
+        string? rootPath = Path.GetDirectoryName(projectFilePath);
+
+        if (rootPath is null)
+        {
+            return null;
+        }
 
         return Path.Combine(rootPath, relativePath);
     }

src/Microsoft.VisualStudio.ProjectSystem.Managed/ProjectSystem/SpecialFileProviders/AppDesignerFolderSpecialFileProvider.cs

@@ -40,7 +40,7 @@ public AppDesignerFolderSpecialFileProvider(IPhysicalProjectTree projectTree, Pr
             return null;
 
         string? folderName = await GetDefaultAppDesignerFolderNameAsync();
-        if (string.IsNullOrEmpty(folderName))
+        if (Strings.IsNullOrEmpty(folderName))
             return null; // Developer has set the AppDesigner path to empty
 
         return Path.Combine(projectPath, folderName);

src/Microsoft.VisualStudio.ProjectSystem.Managed/ProjectSystem/Tree/Order/TreeItemOrderPropertyProvider.cs

@@ -24,7 +24,13 @@ private static string[] GetPathComponents(string evaluatedInclude)
 
     private static string[] GetPathFolders(string path)
     {
-        return GetPathComponents(Path.GetDirectoryName(path));
+        string? evaluatedInclude = Path.GetDirectoryName(path);
+        if (evaluatedInclude is null)
+        {
+            return [];
+        }
+
+        return GetPathComponents(evaluatedInclude);
     }
 
     /// <summary>

tests/Microsoft.VisualStudio.ProjectSystem.Managed.TestServices/ProjectSystem/ProjectTreeProvider.cs

@@ -68,7 +68,7 @@ public Task<bool> CanRenameAsync(IProjectTree node)
         if (target.IsRoot())
             return string.Empty;
 
-        return Path.Combine(GetAddNewItemDirectory(target.Parent!), target.Caption);
+        return Path.Combine(GetAddNewItemDirectory(target.Parent!)!, target.Caption);
     }
 
     public string? GetPath(IProjectTree node)

tests/Microsoft.VisualStudio.ProjectSystem.Managed.UnitTests/Utilities/RepoUtil.cs

@@ -17,10 +17,10 @@ public static string FindRepoRootPath()
         if (_root is null)
         {
             // Start with this DLL's location
-            string path = typeof(RepoUtil).Assembly.Location;
+            string? path = typeof(RepoUtil).Assembly.Location;
 
             // Walk up the tree until we find the 'artifacts' folder
-            while (!Path.GetFileName(path).Equals("artifacts", StringComparisons.Paths))
+            while (Path.GetFileName(path)?.Equals("artifacts", StringComparisons.Paths) is false)
             {
                 path = Path.GetDirectoryName(path);
             }
@@ -29,6 +29,8 @@ public static string FindRepoRootPath()
             _root = Path.GetDirectoryName(path);
         }
 
+        Assumes.NotNull(_root);
+
         return _root;
     }
 }

tests/Microsoft.VisualStudio.ProjectSystem.Managed.VS.UnitTests/ProjectSystem/VS/Rules/DependencyRuleTests.cs

@@ -273,7 +273,7 @@ public static IEnumerable<object[]> GetResolvedAndUnresolvedDependencyRulePairs(
         {
             string unresolvedName = Path.GetFileNameWithoutExtension(unresolvedPath);
             string resolvedName = "Resolved" + unresolvedName;
-            string resolvedPath = Path.Combine(Path.GetDirectoryName(unresolvedPath), resolvedName + ".xaml");
+            string resolvedPath = Path.Combine(Path.GetDirectoryName(unresolvedPath)!, resolvedName + ".xaml");
 
             Assert.Contains(resolvedPath, resolvedPaths);
 

tests/Microsoft.VisualStudio.ProjectSystem.Managed.VS.UnitTests/ProjectSystem/VS/Rules/XamlRuleTestBase.cs

@@ -24,7 +24,7 @@ public abstract class XamlRuleTestBase
 
         foreach ((string basePath, Type assemblyExporterType) in projects)
         {
-            string path = string.IsNullOrEmpty(suffix) ? basePath : Path.Combine(basePath, suffix);
+            string path = Strings.IsNullOrEmpty(suffix) ? basePath : Path.Combine(basePath, suffix);
 
             if (Directory.Exists(path))
             {