Add SDK analyzer assembly redirector

src/VisualStudio/CSharp/Test/ProjectSystemShim/SdkAnalyzerAssemblyRedirectorTests.cs

@@ -0,0 +1,86 @@
+// 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 file in the project root for more information.
+
+using System.Collections.Generic;
+using System.IO;
+using System.Text.Json;
+using Microsoft.VisualStudio.LanguageServices.ProjectSystem;
+using Roslyn.Test.Utilities;
+using Xunit;
+
+namespace Roslyn.VisualStudio.CSharp.UnitTests.ProjectSystemShim;
+
+public sealed class SdkAnalyzerAssemblyRedirectorTests : TestBase
+{
+    [Theory]
+    [InlineData("9.0.0-preview.5.24306.11", "9.0.0-preview.7.24406.2")]
+    [InlineData("9.0.0-preview.5.24306.11", "9.0.1-preview.7.24406.2")]
+    [InlineData("9.0.100", "9.0.0-preview.7.24406.2")]
+    [InlineData("9.0.100", "9.0.200")]
+    [InlineData("9.0.100", "9.0.101")]
+    public void SameMajorMinorVersion(string a, string b)
+    {
+        var testDir = Temp.CreateDirectory();
+
+        var vsDir = Path.Combine(testDir.Path, "vs");
+        Metadata(vsDir, new() { { "AspNetCoreAnalyzers", a } });
+        var vsAnalyzerPath = FakeDll(vsDir, @$"AspNetCoreAnalyzers\analyzers\dotnet\cs", "Microsoft.AspNetCore.App.Analyzers");
+        var sdkAnalyzerPath = FakeDll(testDir.Path, @$"sdk\packs\Microsoft.AspNetCore.App.Ref\{b}\analyzers\dotnet\cs", "Microsoft.AspNetCore.App.Analyzers");
+
+        var resolver = new SdkAnalyzerAssemblyRedirectorCore(vsDir);
+        var redirected = resolver.RedirectPath(sdkAnalyzerPath);
+        AssertEx.Equal(vsAnalyzerPath, redirected);
+    }
+
+    [Fact]
+    public void DifferentPathSuffix()
+    {
+        var testDir = Temp.CreateDirectory();
+
+        var vsDir = Path.Combine(testDir.Path, "vs");
+        Metadata(vsDir, new() { { "AspNetCoreAnalyzers", "9.0.0-preview.5.24306.11" } });
+        FakeDll(vsDir, @"AspNetCoreAnalyzers\analyzers\dotnet\cs", "Microsoft.AspNetCore.App.Analyzers");
+        var sdkAnalyzerPath = FakeDll(testDir.Path, @"sdk\packs\Microsoft.AspNetCore.App.Ref\9.0.0-preview.7.24406.2\analyzers\dotnet\vb", "Microsoft.AspNetCore.App.Analyzers");
+
+        var resolver = new SdkAnalyzerAssemblyRedirectorCore(vsDir);
+        var redirected = resolver.RedirectPath(sdkAnalyzerPath);
+        Assert.Null(redirected);
+    }
+
+    [Theory]
+    [InlineData("8.0.100", "9.0.0-preview.7.24406.2")]
+    [InlineData("9.1.100", "9.0.0-preview.7.24406.2")]
+    [InlineData("9.1.0-preview.5.24306.11", "9.0.0-preview.7.24406.2")]
+    [InlineData("9.0.100", "9.1.100")]
+    [InlineData("9.0.100", "10.0.100")]
+    [InlineData("9.9.100", "9.10.100")]
+    public void DifferentMajorMinorVersion(string a, string b)
+    {
+        var testDir = Temp.CreateDirectory();
+
+        var vsDir = Path.Combine(testDir.Path, "vs");
+        Metadata(vsDir, new() { { "AspNetCoreAnalyzers", a } });
+        FakeDll(vsDir, @$"AspNetCoreAnalyzers\analyzers\dotnet\cs", "Microsoft.AspNetCore.App.Analyzers");
+        var sdkAnalyzerPath = FakeDll(testDir.Path, @$"sdk\packs\Microsoft.AspNetCore.App.Ref\{b}\analyzers\dotnet\cs", "Microsoft.AspNetCore.App.Analyzers");
+
+        var resolver = new SdkAnalyzerAssemblyRedirectorCore(vsDir);
+        var redirected = resolver.RedirectPath(sdkAnalyzerPath);
+        Assert.Null(redirected);
+    }
+
+    private static string FakeDll(string root, string subdir, string name)
+    {
+        var dllPath = Path.Combine(root, subdir, $"{name}.dll");
+        Directory.CreateDirectory(Path.GetDirectoryName(dllPath));
+        File.WriteAllText(dllPath, "");
+        return dllPath;
+    }
+
+    private static void Metadata(string root, Dictionary<string, string> versions)
+    {
+        var metadataFilePath = Path.Combine(root, "metadata.json");
+        Directory.CreateDirectory(Path.GetDirectoryName(metadataFilePath));
+        File.WriteAllText(metadataFilePath, JsonSerializer.Serialize(versions));
+    }
+}

src/VisualStudio/Core/Def/ProjectSystem/SdkAnalyzerAssemblyRedirector.cs

@@ -0,0 +1,190 @@
+// 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 file in the project root for more information.
+
+using System;
+using System.Collections.Generic;
+using System.Collections.Immutable;
+using System.ComponentModel.Composition;
+using System.IO;
+using System.Text.Json;
+using Microsoft.CodeAnalysis.Host.Mef;
+using Microsoft.CodeAnalysis.Workspaces.AnalyzerRedirecting;
+using Microsoft.VisualStudio.Shell;
+using Microsoft.VisualStudio.Shell.Interop;
+
+// Example:
+// FullPath: "C:\Program Files\dotnet\packs\Microsoft.WindowsDesktop.App.Ref\8.0.8\analyzers\dotnet\System.Windows.Forms.Analyzers.dll"
+// ProductVersion: "8.0.8"
+// PathSuffix: "analyzers\dotnet"
+using AnalyzerInfo = (string FullPath, string ProductVersion, string PathSuffix);
+
+namespace Microsoft.VisualStudio.LanguageServices.ProjectSystem;
+
+/// <summary>
+/// See <see href="https://github.com/dotnet/sdk/blob/main/documentation/general/analyzer-redirecting.md"/>.
+/// </summary>
+[Export(typeof(IAnalyzerAssemblyRedirector))]
+[method: ImportingConstructor]
+[method: Obsolete(MefConstruction.ImportingConstructorMessage, error: true)]
+internal sealed class SdkAnalyzerAssemblyRedirector(SVsServiceProvider serviceProvider) : SdkAnalyzerAssemblyRedirectorCore(
+    Path.GetFullPath(Path.Combine(AppDomain.CurrentDomain.BaseDirectory, @"CommonExtensions\Microsoft\DotNet")),
+    (IVsActivityLog)serviceProvider.GetService(typeof(SVsActivityLog)));
+
+/// <summary>
+/// Core functionality of <see cref="SdkAnalyzerAssemblyRedirector"/> extracted for testing.
+/// </summary>
+internal class SdkAnalyzerAssemblyRedirectorCore : IAnalyzerAssemblyRedirector
+{
+    private readonly IVsActivityLog? _log;
+
+    private readonly bool _enabled;
+
+    private readonly string? _insertedAnalyzersDirectory;
+
+    /// <summary>
+    /// Map from analyzer assembly name (file name without extension) to a list of matching analyzers.
+    /// </summary>
+    private readonly ImmutableDictionary<string, List<AnalyzerInfo>> _analyzerMap;
+
+    public SdkAnalyzerAssemblyRedirectorCore(string? insertedAnalyzersDirectory, IVsActivityLog? log = null)
+    {
+        _log = log;
+        var enable = Environment.GetEnvironmentVariable("DOTNET_ANALYZER_REDIRECTING");
+        _enabled = !"0".Equals(enable, StringComparison.OrdinalIgnoreCase) && !"false".Equals(enable, StringComparison.OrdinalIgnoreCase);
+        _insertedAnalyzersDirectory = insertedAnalyzersDirectory;
+        _analyzerMap = CreateAnalyzerMap();
+    }
+
+    private ImmutableDictionary<string, List<AnalyzerInfo>> CreateAnalyzerMap()
+    {
+        if (!_enabled)
+        {
+            Log("Analyzer redirecting is disabled.");
+            return ImmutableDictionary<string, List<AnalyzerInfo>>.Empty;
+        }
+
+        var metadataFilePath = Path.Combine(_insertedAnalyzersDirectory, "metadata.json");
+        if (!File.Exists(metadataFilePath))
+        {
+            Log($"File does not exist: {metadataFilePath}");
+            return ImmutableDictionary<string, List<AnalyzerInfo>>.Empty;
+        }
+
+        var versions = JsonSerializer.Deserialize<Dictionary<string, string>>(File.ReadAllText(metadataFilePath));
+        if (versions is null || versions.Count == 0)
+        {
+            Log($"Versions are empty: {metadataFilePath}");
+            return ImmutableDictionary<string, List<AnalyzerInfo>>.Empty;
+        }
+
+        var builder = ImmutableDictionary.CreateBuilder<string, List<AnalyzerInfo>>(StringComparer.OrdinalIgnoreCase);
+
+        // Expects layout like:
+        // VsInstallDir\DotNetRuntimeAnalyzers\WindowsDesktopAnalyzers\analyzers\dotnet\System.Windows.Forms.Analyzers.dll
+        //                                     ~~~~~~~~~~~~~~~~~~~~~~~                                                     = topLevelDirectory
+        //                                                             ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ = analyzerPath
+
+        foreach (var topLevelDirectory in Directory.EnumerateDirectories(_insertedAnalyzersDirectory))
+        {
+            foreach (var analyzerPath in Directory.EnumerateFiles(topLevelDirectory, "*.dll", SearchOption.AllDirectories))
+            {
+                if (!analyzerPath.StartsWith(topLevelDirectory, StringComparison.OrdinalIgnoreCase))
+                {
+                    continue;
+                }
+
+                var subsetName = Path.GetFileName(topLevelDirectory);
+                if (!versions.TryGetValue(subsetName, out var version))
+                {
+                    continue;
+                }
+
+                var analyzerName = Path.GetFileNameWithoutExtension(analyzerPath);
+                var pathSuffix = analyzerPath.Substring(topLevelDirectory.Length + 1 /* slash */);
+                pathSuffix = Path.GetDirectoryName(pathSuffix);
+
+                AnalyzerInfo analyzer = new() { FullPath = analyzerPath, ProductVersion = version, PathSuffix = pathSuffix };
+
+                if (builder.TryGetValue(analyzerName, out var existing))
+                {
+                    existing.Add(analyzer);
+                }
+                else
+                {
+                    builder.Add(analyzerName, [analyzer]);
+                }
+            }
+        }
+
+        Log($"Loaded analyzer map ({builder.Count}): {_insertedAnalyzersDirectory}");
+
+        return builder.ToImmutable();
+    }
+
+    public string? RedirectPath(string fullPath)
+    {
+        if (_enabled && _analyzerMap.TryGetValue(Path.GetFileNameWithoutExtension(fullPath), out var analyzers))
+        {
+            foreach (var analyzer in analyzers)
+            {
+                var directoryPath = Path.GetDirectoryName(fullPath);
+
+                // Note that both paths we compare here are normalized via netfx's Path.GetDirectoryName.
+                if (directoryPath.EndsWith(analyzer.PathSuffix, StringComparison.OrdinalIgnoreCase) &&
+                    MajorAndMinorVersionsMatch(directoryPath, analyzer.PathSuffix, analyzer.ProductVersion))
+                {
+                    return analyzer.FullPath;
+                }
+            }
+        }
+
+        return null;
+
+        static bool MajorAndMinorVersionsMatch(string directoryPath, string pathSuffix, string version)
+        {
+            // Find the version number in the directory path - it is in the directory name before the path suffix.
+            // Example:
+            // "C:\Program Files\dotnet\packs\Microsoft.WindowsDesktop.App.Ref\8.0.8\analyzers\dotnet\" = directoryPath
+            //                                                                       ~~~~~~~~~~~~~~~~   = pathSuffix
+            //                                                                 ~~~~~                    = directoryPathVersion
+            // This can match also a NuGet package because the version number is at the same position:
+            // "C:\.nuget\packages\Microsoft.WindowsDesktop.App.Ref\8.0.8\analyzers\dotnet\"
+
+            var index = directoryPath.LastIndexOf(pathSuffix, StringComparison.OrdinalIgnoreCase);
+            if (index < 0)
+            {
+                return false;
+            }
+
+            var directoryPathVersion = Path.GetFileName(Path.GetDirectoryName(directoryPath.Substring(0, index)));
+
+            return AreVersionMajorMinorPartEqual(directoryPathVersion, version);
+        }
+
+        static bool AreVersionMajorMinorPartEqual(string version1, string version2)
+        {
+            var firstDotIndex = version1.IndexOf('.');
+            if (firstDotIndex < 0)
+            {
+                return false;
+            }
+
+            var secondDotIndex = version1.IndexOf('.', firstDotIndex + 1);
+            if (secondDotIndex < 0)
+            {
+                return false;
+            }
+
+            return 0 == string.Compare(version1, 0, version2, 0, secondDotIndex, StringComparison.OrdinalIgnoreCase);
+        }
+    }
+
+    private void Log(string message)
+    {
+        _log?.LogEntry(
+            (uint)__ACTIVITYLOG_ENTRYTYPE.ALE_INFORMATION,
+            "Roslyn" + nameof(SdkAnalyzerAssemblyRedirector),
+            message);
+    }
+}