C#: Do not pass around the set of reachable feeds. This implicitly delays the calculation of the reachable feeds until it is needed/used.

Author: michaelnebel

csharp/extractor/Semmle.Extraction.CSharp.DependencyFetching/FeedManager.cs

@@ -170,9 +170,8 @@ public string FeedsToRestoreArgument(IEnumerable<string> feeds, string sourceArg
         /// (2) Use private registries, if they are configured
         /// </summary>
         /// <param name="path">Path to project/solution/packages.config</param>
-        /// <param name="reachableFeeds">The set of reachable NuGet feeds.</param>
         /// <returns>The list of NuGet feeds to use for this restore.</returns>
-        public IEnumerable<string> FeedsToUse(string path, ImmutableHashSet<string> reachableFeeds)
+        public IEnumerable<string> FeedsToUse(string path)
         {
             // Find the path specific feeds.
             var folder = GetDirectoryName(path);
@@ -184,7 +183,7 @@ public IEnumerable<string> FeedsToUse(string path, ImmutableHashSet<string> reac
             }
 
             var feedsToUse = CheckNugetFeedResponsiveness
-                ? feedsToConsider.Where(reachableFeeds.Contains)
+                ? feedsToConsider.Where(ReachableFeeds.Contains)
                 : feedsToConsider;
 
             return feedsToUse;
@@ -196,17 +195,16 @@ public IEnumerable<string> FeedsToUse(string path, ImmutableHashSet<string> reac
         /// (2) Use private registries, if they are configured
         /// </summary>
         /// <param name="path">Path to project/solution</param>
-        /// <param name="reachableFeeds">The set of reachable NuGet feeds.</param>
         /// <returns>A string representing the NuGet sources argument for the restore command.</returns>
-        public string? MakeDotnetRestoreSourcesArgument(string path, ImmutableHashSet<string> reachableFeeds)
+        public string? MakeDotnetRestoreSourcesArgument(string path)
         {
             // Do not construct a set of explicit NuGet sources to use for restore.
             if (!CheckNugetFeedResponsiveness && !HasPrivateRegistryFeeds)
             {
                 return null;
             }
 
-            var feedsToUse = FeedsToUse(path, reachableFeeds);
+            var feedsToUse = FeedsToUse(path);
 
             return FeedsToRestoreArgument(feedsToUse, "-s");
         }

csharp/extractor/Semmle.Extraction.CSharp.DependencyFetching/NugetPackageRestorer.cs

@@ -110,8 +110,6 @@ public HashSet<AssemblyLookupLocation> Restore()
             logger.LogInfo($"Checking NuGet feed responsiveness: {feedManager.CheckNugetFeedResponsiveness}");
             compilationInfoContainer.CompilationInfos.Add(("NuGet feed responsiveness checked", feedManager.CheckNugetFeedResponsiveness ? "1" : "0"));
 
-            ImmutableHashSet<string> reachableFeeds = [];
-
             EmitNugetConfigDiagnostics();
 
             // Find feeds that are configured in NuGet.config files and divide them into ones that
@@ -141,12 +139,11 @@ public HashSet<AssemblyLookupLocation> Restore()
                         : [unresponsiveMissingPackageLocation];
                 }
 
-                reachableFeeds = feedManager.ReachableFeeds;
             }
 
             try
             {
-                var packagesConfigRestore = PackagesConfigRestoreFactory.Create(fileProvider, legacyPackageDirectory, logger, feedManager, reachableFeeds);
+                var packagesConfigRestore = PackagesConfigRestoreFactory.Create(fileProvider, legacyPackageDirectory, logger, feedManager);
                 var count = packagesConfigRestore.InstallPackages();
                 if (packagesConfigRestore.PackageCount > 0)
                 {
@@ -184,9 +181,9 @@ public HashSet<AssemblyLookupLocation> Restore()
             }
 
             // Restore project dependencies with `dotnet restore`.
-            var restoredProjects = RestoreSolutions(reachableFeeds, out var container);
+            var restoredProjects = RestoreSolutions(out var container);
             var projects = fileProvider.Projects.Except(restoredProjects);
-            RestoreProjects(projects, reachableFeeds, out var containers);
+            RestoreProjects(projects, out var containers);
 
             var dependencies = containers.Flatten(container);
 
@@ -218,7 +215,7 @@ public HashSet<AssemblyLookupLocation> Restore()
         /// Populates dependencies with the relevant dependencies from the assets files generated by the restore.
         /// Returns a list of projects that are up to date with respect to restore.
         /// </summary>
-        private IEnumerable<string> RestoreSolutions(ImmutableHashSet<string> reachableFeeds, out DependencyContainer dependencies)
+        private IEnumerable<string> RestoreSolutions(out DependencyContainer dependencies)
         {
             var successCount = 0;
             var nugetSourceFailures = 0;
@@ -231,7 +228,7 @@ private IEnumerable<string> RestoreSolutions(ImmutableHashSet<string> reachableF
             var projects = fileProvider.Solutions.SelectMany(solution =>
                 {
                     logger.LogInfo($"Restoring solution {solution}...");
-                    var nugetSources = feedManager.MakeDotnetRestoreSourcesArgument(solution, reachableFeeds);
+                    var nugetSources = feedManager.MakeDotnetRestoreSourcesArgument(solution);
                     var res = dotnet.Restore(new(solution, PackageDirectory.DirInfo.FullName, ForceDotnetRefAssemblyFetching: true, NugetSources: nugetSources, TargetWindows: isWindows));
                     if (res.Success)
                     {
@@ -262,8 +259,7 @@ private IEnumerable<string> RestoreSolutions(ImmutableHashSet<string> reachableF
         /// Populates dependencies with the relative paths to the assets files generated by the restore.
         /// </summary>
         /// <param name="projects">A list of paths to project files.</param>
-        /// <param name="reachableFeeds">The set of reachable NuGet feeds.</param>
-        private void RestoreProjects(IEnumerable<string> projects, ImmutableHashSet<string> reachableFeeds, out ConcurrentBag<DependencyContainer> dependencies)
+        private void RestoreProjects(IEnumerable<string> projects, out ConcurrentBag<DependencyContainer> dependencies)
         {
             var successCount = 0;
             var nugetSourceFailures = 0;
@@ -280,7 +276,7 @@ private void RestoreProjects(IEnumerable<string> projects, ImmutableHashSet<stri
                 foreach (var project in projectGroup)
                 {
                     logger.LogInfo($"Restoring project {project}...");
-                    var nugetSources = feedManager.MakeDotnetRestoreSourcesArgument(project, reachableFeeds);
+                    var nugetSources = feedManager.MakeDotnetRestoreSourcesArgument(project);
                     var res = dotnet.Restore(new(project, PackageDirectory.DirInfo.FullName, ForceDotnetRefAssemblyFetching: true, NugetSources: nugetSources, TargetWindows: isWindows));
                     assets.AddDependenciesRange(res.AssetsFilePaths);
                     lock (sync)

csharp/extractor/Semmle.Extraction.CSharp.DependencyFetching/PackagesConfigRestorer.cs

@@ -34,11 +34,11 @@ internal interface IPackagesConfigRestore
     /// </summary>
     internal class PackagesConfigRestoreFactory
     {
-        public static IPackagesConfigRestore Create(FileProvider fileProvider, DependencyDirectory packageDirectory, Semmle.Util.Logging.ILogger logger, FeedManager feedManager, ImmutableHashSet<string> reachableFeeds)
+        public static IPackagesConfigRestore Create(FileProvider fileProvider, DependencyDirectory packageDirectory, Semmle.Util.Logging.ILogger logger, FeedManager feedManager)
         {
             if (SystemBuildActions.Instance.IsWindows() || SystemBuildActions.Instance.IsMonoInstalled())
             {
-                return new NugetExeWrapper(fileProvider, packageDirectory, logger, feedManager, reachableFeeds);
+                return new NugetExeWrapper(fileProvider, packageDirectory, logger, feedManager);
             }
 
             return new NoOpPackagesConfig(fileProvider.PackagesConfigs, logger);
@@ -65,7 +65,6 @@ private class NugetExeWrapper : IPackagesConfigRestore
             /// </summary>
             private readonly DependencyDirectory packageDirectory;
             private readonly FeedManager feedManager;
-            private readonly ImmutableHashSet<string> reachableFeeds;
 
             private bool IsWindows => SystemBuildActions.Instance.IsWindows();
 
@@ -76,13 +75,12 @@ private class NugetExeWrapper : IPackagesConfigRestore
             /// <summary>
             /// Create the package manager for a specified source tree.
             /// </summary>
-            public NugetExeWrapper(FileProvider fileProvider, DependencyDirectory packageDirectory, Semmle.Util.Logging.ILogger logger, FeedManager feedManager, ImmutableHashSet<string> reachableFeeds)
+            public NugetExeWrapper(FileProvider fileProvider, DependencyDirectory packageDirectory, Semmle.Util.Logging.ILogger logger, FeedManager feedManager)
             {
                 this.fileProvider = fileProvider;
                 this.packageDirectory = packageDirectory;
                 this.logger = logger;
                 this.feedManager = feedManager;
-                this.reachableFeeds = reachableFeeds;
 
                 if (fileProvider.PackagesConfigs.Count > 0)
                 {
@@ -171,7 +169,7 @@ private bool TryRestoreNugetPackage(string packagesConfig)
                 logger.LogInfo($"Restoring file \"{packagesConfig}\"...");
 
                 var sourcesArgument = "";
-                var feedsToUse = feedManager.FeedsToUse(packagesConfig, reachableFeeds).ToList();
+                var feedsToUse = feedManager.FeedsToUse(packagesConfig).ToList();
                 var useDefaultFeed = feedsToUse.Count == 0 && IsDefaultFeedReachable;
 
                 // Explicitly construct the sources to be used for the restore command when checking feed