fix: fix system packages not being found

src/Core/Liz.Core.IntegrationTests/FindPackageReferenceArtifactTests.cs

@@ -14,10 +14,10 @@ public class FindPackageReferenceArtifactTests
     [InlineData("abc", "1.33.7", false)]
     public async Task Finds_Package_Reference_Artifact(string packageName, string packageVersion, bool expectedOutcome)
     {
+        var fileSystem = new FileSystem();
         var logger = new Logging.Null.NullLogger();
         var cliExecutor = new DefaultCliToolExecutor(logger);
-        var provideNugetCaches = new ProvideNugetCacheDirectories(cliExecutor);
-        var fileSystem = new FileSystem();
+        var provideNugetCaches = new ProvideNugetCacheDirectories(cliExecutor, fileSystem);
 
         var findPackageReferenceArtifact = new FindPackageReferenceArtifact(provideNugetCaches, fileSystem, logger);
 

src/Core/Liz.Core.Tests/Utils/ProvideNugetCacheDirectoriesTests.cs

@@ -3,6 +3,8 @@
 using Liz.Core.CliTool.Contracts;
 using Liz.Core.Utils;
 using Moq;
+using System.IO.Abstractions;
+using System.IO.Abstractions.TestingHelpers;
 using Xunit;
 
 namespace Liz.Core.Tests.Utils;
@@ -13,6 +15,8 @@ public class ProvideNugetCacheDirectoriesTests
     public async Task Provides_Cache_Directories()
     {
         var context = ArrangeContext<ProvideNugetCacheDirectories>.Create();
+        context.Use<IFileSystem>(new MockFileSystem());
+
         var sut = context.Build();
 
         const string expectedDirectory = @"C:\Users\some-user\.nuget\packages\";
@@ -26,7 +30,7 @@ public async Task Provides_Cache_Directories()
 
         result
             .Should()
-            .OnlyContain(directory => directory == expectedDirectory);
+            .Contain(directory => directory == expectedDirectory);
 
         // getting the directory should be cached, so a second call should just return the cache
         _ = await sut.GetAsync();

src/Core/Liz.Core/ExtractLicensesFactory.cs

@@ -111,7 +111,7 @@ public IExtractLicenses Create(
             new ExportLicenseTextsResultProcessor(settings, fileSystem)
         };
 
-        var provideNugetCacheDirectories = new ProvideNugetCacheDirectories(cliToolExecutor);
+        var provideNugetCacheDirectories = new ProvideNugetCacheDirectories(cliToolExecutor, fileSystem);
         var findPackageReferenceArtifact = new FindPackageReferenceArtifact(
             provideNugetCacheDirectories,
             fileSystem,

src/Core/Liz.Core/Utils/ProvideNugetCacheDirectories.cs

@@ -1,18 +1,22 @@
 using Liz.Core.CliTool.Contracts;
 using Liz.Core.Utils.Contracts;
+using System.IO.Abstractions;
 
 namespace Liz.Core.Utils;
 
 internal sealed class ProvideNugetCacheDirectories : IProvideNugetCacheDirectories
 {
     private readonly ICliToolExecutor _cliToolExecutor;
+    private readonly IFileSystem _fileSystem;
 
     private IEnumerable<string>? _nugetCacheDirectories;
 
     public ProvideNugetCacheDirectories(
-        ICliToolExecutor cliToolExecutor)
+        ICliToolExecutor cliToolExecutor,
+        IFileSystem fileSystem)
     {
         _cliToolExecutor = cliToolExecutor ?? throw new ArgumentNullException(nameof(cliToolExecutor));
+        _fileSystem = fileSystem ?? throw new ArgumentNullException(nameof(fileSystem));
     }
 
     public async Task<IEnumerable<string>> GetAsync()
@@ -22,6 +26,16 @@ public async Task<IEnumerable<string>> GetAsync()
     }
 
     private async Task<IEnumerable<string>> GetCacheDirectoriesAsync()
+    {
+        var cacheDirectories = await GetNugetLocalsGlobalPackagesAsync();
+
+        if (TryGetNugetFallbackFolder(out var nugetFallbackFolder)) 
+            cacheDirectories.Add(nugetFallbackFolder);
+
+        return cacheDirectories;
+    }
+
+    private async Task<IList<string>> GetNugetLocalsGlobalPackagesAsync()
     {
         // refer to https://docs.microsoft.com/en-us/dotnet/core/tools/dotnet-nuget-locals
         var result = await _cliToolExecutor
@@ -32,7 +46,15 @@ private async Task<IEnumerable<string>> GetCacheDirectoriesAsync()
         return cacheDirectories;
     }
 
-    private static IEnumerable<string> ParseCliOutput(string cliOutput)
+    private bool TryGetNugetFallbackFolder(out string nugetFallbackFolder)
+    {
+        var programFiles = Environment.GetFolderPath(Environment.SpecialFolder.ProgramFiles);
+        nugetFallbackFolder = _fileSystem.Path.Combine(programFiles, "dotnet", "sdk", "NuGetFallbackFolder");
+
+        return _fileSystem.Directory.Exists(nugetFallbackFolder);
+    }
+
+    private static IList<string> ParseCliOutput(string cliOutput)
     {
         const string searchString = "global-packages: ";