C#: Also use AssemblyLookupLocation for framework dlls.

Author: michaelnebel

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

@@ -10,7 +10,7 @@ namespace Semmle.Extraction.CSharp.DependencyFetching
     /// Used to represent a path to an assembly or a directory containing assemblies
     /// and a selector function to determine which files to include, when indexing the assemblies.
     /// </summary>
-    internal sealed class AssemblyLookupLocation(string p, Func<string, bool> includeFileName)
+    internal sealed class AssemblyLookupLocation(string p, Func<string, bool> includeFileName, bool indexSubdirectories = true)
     {
         public string Path => p;
 
@@ -26,23 +26,30 @@ public AssemblyLookupLocation(string p) : this(p, _ => true) { }
         /// <param name="dir">The directory to index.</param>
         private void AddReferenceDirectory(List<string> dllsToIndex, ILogger logger)
         {
-            var dlls = new DirectoryInfo(p).EnumerateFiles("*.dll", new EnumerationOptions { RecurseSubdirectories = true, MatchCasing = MatchCasing.CaseInsensitive, AttributesToSkip = FileAttributes.None });
-            if (!dlls.Any())
+            try
             {
-                logger.LogWarning($"AssemblyLookupLocation: No DLLs found in the path '{p}'.");
-                return;
-            }
-            foreach (var dll in dlls)
-            {
-                if (includeFileName(dll.Name))
+                var dlls = new DirectoryInfo(p).EnumerateFiles("*.dll", new EnumerationOptions { RecurseSubdirectories = indexSubdirectories, MatchCasing = MatchCasing.CaseInsensitive, AttributesToSkip = FileAttributes.None });
+                if (!dlls.Any())
                 {
-                    dllsToIndex.Add(dll.FullName);
+                    logger.LogWarning($"AssemblyLookupLocation: No DLLs found in the path '{p}'.");
+                    return;
                 }
-                else
+                foreach (var dll in dlls)
                 {
-                    logger.LogInfo($"AssemblyLookupLocation: Skipping {dll.FullName}.");
+                    if (includeFileName(dll.Name))
+                    {
+                        dllsToIndex.Add(dll.FullName);
+                    }
+                    else
+                    {
+                        logger.LogInfo($"AssemblyLookupLocation: Skipping {dll.FullName}.");
+                    }
                 }
             }
+            catch (Exception e)
+            {
+                logger.LogError($"AssemblyLookupLocation: Error while searching for DLLs in '{p}': {e.Message}");
+            }
         }
 
         /// <summary>

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

@@ -214,29 +214,8 @@ private HashSet<string> AddFrameworkDlls(HashSet<AssemblyLookupLocation> dllPath
                         continue;
                     }
 
-                    if (useSubfolders)
-                    {
-                        dllPaths.Add(path);
-                        frameworkLocations.Add(path);
-                        continue;
-                    }
-
-                    try
-                    {
-                        var dlls = Directory.GetFiles(path, "*.dll", new EnumerationOptions { RecurseSubdirectories = false, MatchCasing = MatchCasing.CaseInsensitive });
-                        if (dlls.Length == 0)
-                        {
-                            logger.LogError($"No DLLs found in specified framework reference path '{path}'.");
-                            continue;
-                        }
-
-                        dllPaths.UnionWith(dlls.Select(x => new AssemblyLookupLocation(x)));
-                        frameworkLocations.UnionWith(dlls);
-                    }
-                    catch (Exception e)
-                    {
-                        logger.LogError($"Error while searching for DLLs in '{path}': {e.Message}");
-                    }
+                    dllPaths.Add(new AssemblyLookupLocation(path, _ => true, useSubfolders));
+                    frameworkLocations.Add(path);
                 }
 
                 return frameworkLocations;