Exclude private assets

Author: Forgind

src/Tasks/Microsoft.NET.Build.Tasks/DependencyContextBuilder.cs

@@ -22,6 +22,7 @@ internal class DependencyContextBuilder
         private Dictionary<string, List<ReferenceInfo>> _compileReferences;
         private Dictionary<string, List<ResolvedFile>> _resolvedNuGetFiles;
         private Dictionary<string, SingleProjectInfo> _referenceProjectInfos;
+        private IEnumerable<string> _excludeFromPublishPackageIds;
         private Dictionary<string, List<RuntimePackAssetInfo>> _runtimePackAssets;
         private CompilationOptions _compilationOptions;
         private string _referenceAssembliesPath;
@@ -204,6 +205,12 @@ public DependencyContextBuilder WithReferenceProjectInfos(Dictionary<string, Sin
             return this;
         }
 
+        public DependencyContextBuilder WithExcludeFromPublishAssets(IEnumerable<string> excludeFromPublishPackageIds)
+        {
+            _excludeFromPublishPackageIds = excludeFromPublishPackageIds;
+            return this;
+        }
+
         public DependencyContextBuilder WithMainProjectInDepsFile(bool includeMainProjectInDepsFile)
         {
             _includeMainProjectInDepsFile = includeMainProjectInDepsFile;
@@ -814,6 +821,38 @@ private void CalculateExcludedLibraries()
             {
                 _dependencyLibraries[packageToExcludeFromRuntime].ExcludeFromRuntime = true;
             }
+
+            //  Include transitive dependencies of all top-level dependencies
+            Dictionary<string, DependencyLibrary> includedDependencies = new(StringComparer.OrdinalIgnoreCase);
+            Stack<string> dependencyListToWalk = new(_mainProjectDependencies);
+
+            while (dependencyListToWalk.Count != 0)
+            {
+                var dependencyName = dependencyListToWalk.Pop();
+                if (!includedDependencies.ContainsKey(dependencyName) && _excludeFromPublishPackageIds?.Contains(dependencyName) != true)
+                {
+                    //  There may not be a library in the assets file if a referenced project has
+                    //  PrivateAssets="all" for a package reference, and there is a package in the graph
+                    //  that depends on the same package.
+                    if (_dependencyLibraries.TryGetValue(dependencyName, out var dependencyLibrary))
+                    {
+                        includedDependencies.Add(dependencyName, dependencyLibrary);
+                        foreach (var newDependency in _libraryDependencies[dependencyName])
+                        {
+                            dependencyListToWalk.Push(newDependency.Name);
+                        }
+                    }
+                }
+            }
+
+            foreach (var dependencyLibrary in _dependencyLibraries.Values)
+            {
+                if (!includedDependencies.ContainsKey(dependencyLibrary.Name))
+                {
+                    dependencyLibrary.ExcludeFromCompilation = true;
+                    dependencyLibrary.ExcludeFromRuntime = true;
+                }
+            }
         }
 
         private string GetReferenceLibraryName(ReferenceInfo reference)

src/Tasks/Microsoft.NET.Build.Tasks/GenerateDepsFile.cs

@@ -64,6 +64,8 @@ public class GenerateDepsFile : TaskBase
 
         public ITaskItem CompilerOptions { get; set; }
 
+        public ITaskItem[] ExcludeFromPublishPackageReferences { get; set; } = Array.Empty<ITaskItem>();
+
         public ITaskItem[] RuntimeStorePackages { get; set; }
 
         // NuGet compilation assets
@@ -232,6 +234,7 @@ bool ShouldIncludeRuntimeAsset(ITaskItem item)
                 .WithDirectReferences(directReferences)
                 .WithDependencyReferences(dependencyReferences)
                 .WithReferenceProjectInfos(referenceProjects)
+                .WithExcludeFromPublishAssets(PackageReferenceConverter.GetPackageIds(ExcludeFromPublishPackageReferences))
                 .WithRuntimePackAssets(runtimePackAssets)
                 .WithCompilationOptions(compilationOptions)
                 .WithReferenceAssembliesPath(FrameworkReferenceResolver.GetDefaultReferenceAssembliesPath())

src/Tasks/Microsoft.NET.Build.Tasks/targets/Microsoft.NET.Publish.targets

@@ -1236,6 +1236,7 @@ Copyright (c) .NET Foundation. All rights reserved.
                       PlatformLibraryName="$(MicrosoftNETPlatformLibrary)"
                       RuntimeFrameworks="@(RuntimeFramework)"
                       CompilerOptions="@(DependencyFileCompilerOptions)"
+                      ExcludeFromPublishPackageReferences="@(_ExcludeFromPublishPackageReference)"
                       RuntimeStorePackages="@(RuntimeStorePackages)"
                       CompileReferences="@(ResolvedCompileFileDefinitions)"
                       ResolvedNuGetFiles="@(_ResolvedNuGetFilesForPublish)"

src/Tasks/Microsoft.NET.Build.Tasks/targets/Microsoft.NET.Sdk.targets

@@ -338,6 +338,7 @@ Copyright (c) .NET Foundation. All rights reserved.
                       PlatformLibraryName="$(MicrosoftNETPlatformLibrary)"
                       RuntimeFrameworks="@(RuntimeFramework)"
                       CompilerOptions="@(DependencyFileCompilerOptions)"
+                      ExcludeFromPublishPackageReferences="@(_ExcludeFromPublishPackageReference)"
                       CompileReferences="@(ResolvedCompileFileDefinitions)"
                       ResolvedNuGetFiles="@(NativeCopyLocalItems);@(ResourceCopyLocalItems);@(RuntimeCopyLocalItems)"
                       UserRuntimeAssemblies="@(UserRuntimeAssembly)"