Add analyzer section in project.assets.json

Author: martinrrm

src/NuGet.Core/NuGet.Build.Tasks/NuGet.targets

@@ -80,6 +80,12 @@ Copyright (c) .NET Foundation. All rights reserved.
                     AND '$(TargetFrameworkIdentifier)' == '.NETCoreApp'
                     AND $([MSBuild]::VersionGreaterThanOrEquals('$(TargetFrameworkVersion)', '10.0'))">all</NuGetAuditMode>
     <NuGetAuditMode Condition=" '$(NuGetAuditMode)' == '' ">direct</NuGetAuditMode>
+    <!-- Analyzer assets restore is only available for projects targeting .NET 11 or greater. Force the opt-in off for older frameworks. -->
+    <RestoreEnableAnalyzerAssets Condition="'$(RestoreEnableAnalyzerAssets)' == 'true'
+                    AND !('$(TargetFrameworkIdentifier)' == '.NETCoreApp'
+                    AND '$(TargetFrameworkVersion)' != ''
+                    AND $([MSBuild]::VersionGreaterThanOrEquals('$(TargetFrameworkVersion)', '11.0')))">false</RestoreEnableAnalyzerAssets>
+    <RestoreEnableAnalyzerAssets Condition="'$(RestoreEnableAnalyzerAssets)' == '' AND '$(TargetFrameworks)' == ''">false</RestoreEnableAnalyzerAssets>
   </PropertyGroup>
 
   <!-- Package pruning is enabled for all projects targeting .NET 10 or greater, including multi-targeted projects. -->
@@ -864,6 +870,7 @@ Copyright (c) .NET Foundation. All rights reserved.
         <RestoreAdditionalProjectSources>$(RestoreAdditionalProjectSources)</RestoreAdditionalProjectSources>
         <RestoreAdditionalProjectFallbackFolders>$(RestoreAdditionalProjectFallbackFolders)</RestoreAdditionalProjectFallbackFolders>
         <RestoreAdditionalProjectFallbackFoldersExcludes>$(RestoreAdditionalProjectFallbackFoldersExcludes)</RestoreAdditionalProjectFallbackFoldersExcludes>
+        <RestoreEnableAnalyzerAssets>$(RestoreEnableAnalyzerAssets)</RestoreEnableAnalyzerAssets>
       </_RestoreSettingsPerFramework>
     </ItemGroup>
   </Target>
@@ -887,6 +894,18 @@ Copyright (c) .NET Foundation. All rights reserved.
       <Output TaskParameter="AbsolutePaths" PropertyName="RestoreOutputAbsolutePath" />
     </ConvertToAbsolutePath>
 
+    <ItemGroup Condition="'$(TargetFrameworks)' != ''">
+      <_RestoreSettingsWithAnalyzerAssets
+        Include="@(_RestoreSettingsPerFramework)"
+        Condition="'%(_RestoreSettingsPerFramework.RestoreEnableAnalyzerAssets)' == 'true'" />
+    </ItemGroup>
+
+    <PropertyGroup>
+      <_RestoreEffectiveEnableAnalyzerAssets>$(RestoreEnableAnalyzerAssets)</_RestoreEffectiveEnableAnalyzerAssets>
+      <_RestoreEffectiveEnableAnalyzerAssets Condition="'$(TargetFrameworks)' != ''">false</_RestoreEffectiveEnableAnalyzerAssets>
+      <_RestoreEffectiveEnableAnalyzerAssets Condition="'$(TargetFrameworks)' != '' AND '@(_RestoreSettingsWithAnalyzerAssets)' != ''">true</_RestoreEffectiveEnableAnalyzerAssets>
+    </PropertyGroup>
+
     <!--
       Determine project name for the assets file.
       Highest priority: PackageId
@@ -962,6 +981,7 @@ Copyright (c) .NET Foundation. All rights reserved.
         <NETCoreSdkVersion>$(NETCoreSdkVersion)</NETCoreSdkVersion>
         <RestoreUseLegacyDependencyResolver>$(RestoreUseLegacyDependencyResolver)</RestoreUseLegacyDependencyResolver>
         <RestoreDoNotWriteDependencyGraphSpec>$(RestoreDoNotWriteDependencyGraphSpec)</RestoreDoNotWriteDependencyGraphSpec>
+        <RestoreEnableAnalyzerAssets>$(_RestoreEffectiveEnableAnalyzerAssets)</RestoreEnableAnalyzerAssets>
       </_RestoreGraphEntry>
     </ItemGroup>
 

src/NuGet.Core/NuGet.Commands/RestoreCommand/LockFileBuilder.cs

@@ -155,7 +155,9 @@ public LockFile CreateLockFile(LockFile previousLockFile,
 
             var librariesWithWarnings = new HashSet<LibraryIdentity>();
 
-            var rootProjectStyle = project.RestoreMetadata?.ProjectStyle ?? ProjectStyle.Unknown;
+            var restoreMetadata = project.RestoreMetadata;
+            var rootProjectStyle = restoreMetadata?.ProjectStyle ?? ProjectStyle.Unknown;
+            bool restoreEnableAnalyzerAssets = restoreMetadata?.RestoreEnableAnalyzerAssets == true;
 
             // Add the targets
             foreach (var targetGraph in targetGraphs
@@ -238,6 +240,7 @@ public LockFile CreateLockFile(LockFile previousLockFile,
                             dependencyType: includeFlags,
                             targetFrameworkOverride: null,
                             dependencies: graphItem.Data.Dependencies,
+                            restoreEnableAnalyzerAssets: restoreEnableAnalyzerAssets,
                             cache: lockFileBuilderCache);
 
                         target.Libraries.Add(targetLibrary);
@@ -258,6 +261,7 @@ public LockFile CreateLockFile(LockFile previousLockFile,
                                     targetFrameworkOverride: nonFallbackFramework,
                                     dependencyType: includeFlags,
                                     dependencies: graphItem.Data.Dependencies,
+                                    restoreEnableAnalyzerAssets: restoreEnableAnalyzerAssets,
                                     cache: lockFileBuilderCache);
                                 usedFallbackFramework = !targetLibrary.Equals(targetLibraryWithoutFallback);
                             }

src/NuGet.Core/NuGet.Commands/RestoreCommand/LockFileBuilderCache.cs

@@ -31,7 +31,7 @@ public class LockFileBuilderCache
         private readonly ConcurrentDictionary<CriteriaKey, List<(List<SelectionCriteria>, bool)>> _criteriaSets =
             new();
 
-        private readonly ConcurrentDictionary<(CriteriaKey, string path, string aliases, LibraryIncludeFlags, int dependencyCount), Lazy<(LockFileTargetLibrary, bool, NuGetFramework, NuGetFramework)>> _lockFileTargetLibraryCache =
+        private readonly ConcurrentDictionary<(CriteriaKey, string path, string aliases, LibraryIncludeFlags, int dependencyCount, bool restoreEnableAnalyzerAssets), Lazy<(LockFileTargetLibrary, bool, NuGetFramework, NuGetFramework)>> _lockFileTargetLibraryCache =
             new();
 
         /// <summary>
@@ -106,7 +106,7 @@ public ContentItemCollection GetContentItems(LockFileLibrary library, LocalPacka
         /// <summary>
         /// Try to get a LockFileTargetLibrary from the cache.
         /// </summary>
-        internal (LockFileTargetLibrary, bool, NuGetFramework, NuGetFramework) GetLockFileTargetLibrary(RestoreTargetGraph graph, NuGetFramework framework, LocalPackageInfo localPackageInfo, string aliases, LibraryIncludeFlags libraryIncludeFlags, List<LibraryDependency> dependencies, Func<(LockFileTargetLibrary, bool, NuGetFramework, NuGetFramework)> valueFactory)
+        internal (LockFileTargetLibrary, bool, NuGetFramework, NuGetFramework) GetLockFileTargetLibrary(RestoreTargetGraph graph, NuGetFramework framework, LocalPackageInfo localPackageInfo, string aliases, LibraryIncludeFlags libraryIncludeFlags, List<LibraryDependency> dependencies, bool restoreEnableAnalyzerAssets, Func<(LockFileTargetLibrary, bool, NuGetFramework, NuGetFramework)> valueFactory)
         {
             // Comparing RuntimeGraph for equality is very expensive,
             // so in case of a request where the RuntimeGraph is not empty we avoid using the cache.
@@ -116,7 +116,7 @@ public ContentItemCollection GetContentItems(LockFileLibrary library, LocalPacka
             localPackageInfo = localPackageInfo ?? throw new ArgumentNullException(nameof(localPackageInfo));
             var criteriaKey = new CriteriaKey(graph.TargetGraphName, framework);
             var packagePath = localPackageInfo.ExpandedPath;
-            return _lockFileTargetLibraryCache.GetOrAdd((criteriaKey, packagePath, aliases, libraryIncludeFlags, dependencies.Count),
+            return _lockFileTargetLibraryCache.GetOrAdd((criteriaKey, packagePath, aliases, libraryIncludeFlags, dependencies.Count, restoreEnableAnalyzerAssets),
                 key => new Lazy<(LockFileTargetLibrary, bool, NuGetFramework, NuGetFramework)>(valueFactory)).Value;
         }
 

src/NuGet.Core/NuGet.Commands/RestoreCommand/RestoreCommand.cs

@@ -151,6 +151,10 @@ private readonly Dictionary<RestoreTargetGraph, Dictionary<string, LibraryInclud
         private const string PackagePruningRemovablePackagesCount = "Pruning.RemovablePackages.Count";
         private const string PackagePruningDirectCount = "Pruning.Pruned.Direct.Count";
 
+        // Analyzer assets names
+        private const string AnalyzerAssetsEnabled = "AnalyzerAssets.Enabled";
+        private const string AnalyzerAssetsCount = "AnalyzerAssets.Count";
+
         internal readonly bool _enableNewDependencyResolver;
         private readonly bool _isLockFileEnabled;
 
@@ -354,6 +358,7 @@ public async Task<RestoreResult> ExecuteAsync(CancellationToken token)
 
                 telemetry.TelemetryEvent[UpdatedAssetsFile] = restoreResult._isAssetsFileDirty.Value;
                 telemetry.TelemetryEvent[UpdatedMSBuildFiles] = restoreResult._dirtyMSBuildFiles.Value.Count > 0;
+                telemetry.TelemetryEvent[AnalyzerAssetsCount] = CountAnalyzerAssets(assetsFile);
 
                 return restoreResult;
             }
@@ -408,6 +413,7 @@ private void InitializeTelemetry(TelemetryActivity telemetry, int httpSourcesCou
             }
 
             telemetry.TelemetryEvent[AuditEnabled] = auditEnabled ? "enabled" : "disabled";
+            telemetry.TelemetryEvent[AnalyzerAssetsEnabled] = _request.Project.RestoreMetadata?.RestoreEnableAnalyzerAssets ?? false;
 
             PopulatePruningEnabledTelemetry(_request.Project, telemetry.TelemetryEvent);
         }
@@ -453,6 +459,37 @@ internal static void PopulatePruningEnabledTelemetry(PackageSpec project, Teleme
             telemetryEvent[PackagePruningFrameworksUnsupportedCount] = pruningNotApplicableCount;
         }
 
+        /// <summary>
+        /// Counts the analyzer assets written to the assets file, excluding '_._' placeholders that
+        /// represent analyzers excluded from the project. Reflects the depth of analyzer-assets adoption.
+        /// </summary>
+        private static int CountAnalyzerAssets(LockFile assetsFile)
+        {
+            int count = 0;
+
+            foreach (LockFileTarget target in assetsFile.Targets)
+            {
+                foreach (LockFileTargetLibrary library in target.Libraries)
+                {
+                    IList<LockFileItem> analyzerAssets = library.AnalyzerAssets;
+                    if (analyzerAssets == null)
+                    {
+                        continue;
+                    }
+
+                    foreach (LockFileItem asset in analyzerAssets)
+                    {
+                        if (!asset.Path.EndsWith("_._", StringComparison.Ordinal))
+                        {
+                            count++;
+                        }
+                    }
+                }
+            }
+
+            return count;
+        }
+
         private async Task<(RestoreResult, bool, CacheFile)> EvaluateNoOpAsync(TelemetryActivity telemetry, CacheFile cacheFile, Stopwatch restoreTime)
         {
             telemetry.StartIntervalMeasure();