Fix Microsoft.Extensions.AuditReports output path (#4945)

* Fix Microsoft.Extensions.AuditReports output path
* fix golden reports
* add tests and the README

docs/list-of-diagnostics.md

@@ -41,7 +41,6 @@ if desired.
 | `EXTEXP0016` | Hosting integration testing experiments |
 | `EXTEXP0017` | Contextual options experiments |
 
-
 # LoggerMessage
 
 | Diagnostic ID     | Description |
@@ -108,3 +107,10 @@ if desired.
 | `METGEN017` | Gauge is not supported yet |
 | `METGEN018` | Xml comment was not parsed correctly |
 | `METGEN019` | A metric class has cycles in its type hierarchy |
+
+## AuditReports
+
+| Diagnostic ID     | Description |
+| :---------------- | :---------- |
+| `AUDREPGEN000` | MetricsReports generator couldn't resolve output path for the report |
+| `AUDREPGEN001` | ComplianceReports generator couldn't resolve output path for the report |

global.json

@@ -1,9 +1,9 @@
 {
   "sdk": {
-    "version": "8.0.101"
+    "version": "8.0.200"
   },
   "tools": {
-    "dotnet": "8.0.101",
+    "dotnet": "8.0.200",
     "runtimes": {
       "dotnet/x64": [
         "6.0.22"

src/Generators/Microsoft.Gen.ComplianceReports/ComplianceReportsGenerator.cs

@@ -1,9 +1,12 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System.Globalization;
 using System.IO;
+using System.Text;
 using Microsoft.CodeAnalysis;
 using Microsoft.Gen.Shared;
+using Microsoft.Shared.DiagnosticIds;
 
 namespace Microsoft.Gen.ComplianceReports;
 
@@ -18,8 +21,8 @@ public sealed class ComplianceReportsGenerator : ISourceGenerator
 
     private const string FallbackFileName = "ComplianceReport.json";
 
+    private readonly string _fileName;
     private string? _directory;
-    private string _fileName;
 
     public ComplianceReportsGenerator()
         : this(null)
@@ -55,7 +58,7 @@ public void Execute(GeneratorExecutionContext context)
 
         if (!GeneratorUtilities.ShouldGenerateReport(context, GenerateComplianceReportsMSBuildProperty))
         {
-            // By default, compliance reports are only generated only during build time and not during design time to prevent the file being written on every keystroke in VS.
+            // By default, compliance reports are generated only during build time and not during design time to prevent the file being written on every keystroke in VS.
             return;
         }
 
@@ -78,19 +81,30 @@ public void Execute(GeneratorExecutionContext context)
 
         context.CancellationToken.ThrowIfCancellationRequested();
 
-        if (_directory == null)
+        var options = context.AnalyzerConfigOptions.GlobalOptions;
+        _directory ??= GeneratorUtilities.TryRetrieveOptionsValue(options, ComplianceReportOutputPathMSBuildProperty, out var reportOutputPath)
+            ? reportOutputPath!
+            : GeneratorUtilities.GetDefaultReportOutputPath(options);
+
+        if (string.IsNullOrWhiteSpace(_directory))
         {
-            _ = context.AnalyzerConfigOptions.GlobalOptions.TryGetValue(ComplianceReportOutputPathMSBuildProperty, out _directory);
-            if (string.IsNullOrWhiteSpace(_directory))
-            {
-                // no valid output path
-                return;
-            }
+            // Report diagnostic:
+            var diagnostic = new DiagnosticDescriptor(
+                DiagnosticIds.AuditReports.AUDREPGEN001,
+                "ComplianceReports generator couldn't resolve output path for the report. It won't be generated.",
+                "Both <ComplianceReportOutputPath> and <OutputPath> MSBuild properties are not set. The report won't be generated.",
+                nameof(DiagnosticIds.AuditReports),
+                DiagnosticSeverity.Info,
+                isEnabledByDefault: true,
+                helpLinkUri: string.Format(CultureInfo.InvariantCulture, DiagnosticIds.UrlFormat, DiagnosticIds.AuditReports.AUDREPGEN001));
+
+            context.ReportDiagnostic(Diagnostic.Create(diagnostic, location: null));
+            return;
         }
 
         _ = Directory.CreateDirectory(_directory);
 
         // Write report as JSON file.
-        File.WriteAllText(Path.Combine(_directory, _fileName), report);
+        File.WriteAllText(Path.Combine(_directory, _fileName), report, Encoding.UTF8);
     }
 }

src/Generators/Microsoft.Gen.MetricsReports/MetricsReportsGenerator.cs

@@ -2,13 +2,15 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 
 using System.Collections.Generic;
+using System.Globalization;
 using System.IO;
 using System.Linq;
 using System.Text;
 using Microsoft.CodeAnalysis;
 using Microsoft.CodeAnalysis.Diagnostics;
 using Microsoft.Gen.Metrics.Model;
 using Microsoft.Gen.Shared;
+using Microsoft.Shared.DiagnosticIds;
 
 namespace Microsoft.Gen.MetricsReports;
 
@@ -18,13 +20,19 @@ public class MetricsReportsGenerator : ISourceGenerator
     private const string GenerateMetricDefinitionReport = "build_property.GenerateMetricsReport";
     private const string RootNamespace = "build_property.rootnamespace";
     private const string ReportOutputPath = "build_property.MetricsReportOutputPath";
-    private const string CompilationOutputPath = "build_property.outputpath";
-    private const string CurrentProjectPath = "build_property.projectdir";
     private const string FileName = "MetricsReport.json";
 
-    private string? _compilationOutputPath;
-    private string? _currentProjectPath;
-    private string? _reportOutputPath;
+    private readonly string _fileName;
+
+    public MetricsReportsGenerator()
+        : this(FileName)
+    {
+    }
+
+    internal MetricsReportsGenerator(string reportFileName)
+    {
+        _fileName = reportFileName;
+    }
 
     public void Initialize(GeneratorInitializationContext context)
     {
@@ -35,8 +43,9 @@ public void Execute(GeneratorExecutionContext context)
     {
         context.CancellationToken.ThrowIfCancellationRequested();
 
-        var receiver = context.SyntaxReceiver as ClassDeclarationSyntaxReceiver;
-        if (receiver == null || receiver.ClassDeclarations.Count == 0 || !GeneratorUtilities.ShouldGenerateReport(context, GenerateMetricDefinitionReport))
+        if (context.SyntaxReceiver is not ClassDeclarationSyntaxReceiver receiver ||
+            receiver.ClassDeclarations.Count == 0 ||
+            !GeneratorUtilities.ShouldGenerateReport(context, GenerateMetricDefinitionReport))
         {
             return;
         }
@@ -52,13 +61,24 @@ public void Execute(GeneratorExecutionContext context)
 
         var options = context.AnalyzerConfigOptions.GlobalOptions;
 
-        var path = (_reportOutputPath != null || options.TryGetValue(ReportOutputPath, out _reportOutputPath))
-            ? _reportOutputPath
-            : GetDefaultReportOutputPath(options);
+        var path = GeneratorUtilities.TryRetrieveOptionsValue(options, ReportOutputPath, out var reportOutputPath)
+            ? reportOutputPath!
+            : GeneratorUtilities.GetDefaultReportOutputPath(options);
 
         if (string.IsNullOrWhiteSpace(path))
         {
-            // Report diagnostic. Tell that it is either <MetricDefinitionReportOutputPath> missing or <CompilerVisibleProperty Include="OutputPath"/> visibility to compiler.
+            // Report diagnostic:
+            var diagnostic = new DiagnosticDescriptor(
+                DiagnosticIds.AuditReports.AUDREPGEN000,
+                "MetricsReports generator couldn't resolve output path for the report. It won't be generated.",
+                "Both <MetricsReportOutputPath> and <OutputPath> MSBuild properties are not set. The report won't be generated.",
+                nameof(DiagnosticIds.AuditReports),
+                DiagnosticSeverity.Info,
+                isEnabledByDefault: true,
+                helpLinkUri: string.Format(CultureInfo.InvariantCulture, DiagnosticIds.UrlFormat, DiagnosticIds.AuditReports.AUDREPGEN000));
+
+            context.ReportDiagnostic(Diagnostic.Create(diagnostic, location: null));
+
             return;
         }
 
@@ -68,7 +88,7 @@ public void Execute(GeneratorExecutionContext context)
         var reportedMetrics = MapToCommonModel(meteringClasses, rootNamespace);
         var report = emitter.GenerateReport(reportedMetrics, context.CancellationToken);
 
-        File.WriteAllText(Path.Combine(path, FileName), report, Encoding.UTF8);
+        File.WriteAllText(Path.Combine(path, _fileName), report, Encoding.UTF8);
     }
 
     private static ReportedMetricClass[] MapToCommonModel(IReadOnlyList<MetricType> meteringClasses, string? rootNamespace)
@@ -89,19 +109,4 @@ private static ReportedMetricClass[] MapToCommonModel(IReadOnlyList<MetricType>
 
         return reportedMetrics.ToArray();
     }
-
-    private string GetDefaultReportOutputPath(AnalyzerConfigOptions options)
-    {
-        if (_currentProjectPath != null && _compilationOutputPath != null)
-        {
-            return _currentProjectPath + _compilationOutputPath;
-        }
-
-        _ = options.TryGetValue(CompilationOutputPath, out _compilationOutputPath);
-        _ = options.TryGetValue(CurrentProjectPath, out _currentProjectPath);
-
-        return string.IsNullOrWhiteSpace(_currentProjectPath) || string.IsNullOrWhiteSpace(_compilationOutputPath)
-            ? string.Empty
-            : _currentProjectPath + _compilationOutputPath;
-    }
 }

src/Generators/Shared/GeneratorUtilities.cs

@@ -4,11 +4,13 @@
 using System;
 using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
+using System.IO;
 using System.Linq;
 using System.Threading;
 using Microsoft.CodeAnalysis;
 using Microsoft.CodeAnalysis.CSharp;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
+using Microsoft.CodeAnalysis.Diagnostics;
 
 [assembly: System.Resources.NeutralResourcesLanguage("en-us")]
 
@@ -21,6 +23,9 @@ namespace Microsoft.Gen.Shared;
 #endif
 internal static class GeneratorUtilities
 {
+    private const string CompilationOutputPath = "build_property.outputpath";
+    private const string CurrentProjectPath = "build_property.projectdir";
+
     public static string GeneratedCodeAttribute { get; } = $"global::System.CodeDom.Compiler.GeneratedCodeAttribute(" +
                        $"\"{typeof(GeneratorUtilities).Assembly.GetName().Name}\", " +
                        $"\"{typeof(GeneratorUtilities).Assembly.GetName().Version}\")";
@@ -136,4 +141,26 @@ public static bool ShouldGenerateReport(GeneratorExecutionContext context, strin
 
         return string.Equals(generateFiles, bool.TrueString, StringComparison.OrdinalIgnoreCase);
     }
+
+    public static bool TryRetrieveOptionsValue(AnalyzerConfigOptions options, string name, out string? value)
+        => options.TryGetValue(name, out value) && !string.IsNullOrWhiteSpace(value);
+
+    public static string GetDefaultReportOutputPath(AnalyzerConfigOptions options)
+    {
+        if (!TryRetrieveOptionsValue(options, CompilationOutputPath, out var compilationOutputPath))
+        {
+            return string.Empty;
+        }
+
+        // If <OutputPath> is absolute - return it right away:
+        if (Path.IsPathRooted(compilationOutputPath))
+        {
+            return compilationOutputPath!;
+        }
+
+        // Get <ProjectDir> and combine it with <OutputPath> if the former isn't empty:
+        return TryRetrieveOptionsValue(options, CurrentProjectPath, out var currentProjectPath)
+            ? Path.Combine(currentProjectPath!, compilationOutputPath!)
+            : string.Empty;
+    }
 }