Stop updating git-info files when they don't exist (#4866)

Author: Copilot

src/Microsoft.DotNet.Darc/DarcLib/VirtualMonoRepo/VmrDependencyTracker.cs

@@ -8,6 +8,7 @@
 using System.Threading.Tasks;
 using Microsoft.DotNet.DarcLib.Helpers;
 using Microsoft.DotNet.DarcLib.Models.VirtualMonoRepo;
+using Microsoft.Extensions.Logging;
 
 #nullable enable
 namespace Microsoft.DotNet.DarcLib.VirtualMonoRepo;
@@ -47,6 +48,7 @@ public class VmrDependencyTracker : IVmrDependencyTracker
     private readonly IVmrInfo _vmrInfo;
     private readonly IFileSystem _fileSystem;
     private readonly ISourceMappingParser _sourceMappingParser;
+    private readonly ILogger<VmrDependencyTracker> _logger;
     private IReadOnlyCollection<SourceMapping>? _mappings;
 
     public IReadOnlyCollection<SourceMapping> Mappings
@@ -58,12 +60,14 @@ public VmrDependencyTracker(
         IVmrInfo vmrInfo,
         IFileSystem fileSystem,
         ISourceMappingParser sourceMappingParser,
-        ISourceManifest sourceManifest)
+        ISourceManifest sourceManifest,
+        ILogger<VmrDependencyTracker> logger)
     {
         _vmrInfo = vmrInfo;
         _sourceManifest = sourceManifest;
         _fileSystem = fileSystem;
         _sourceMappingParser = sourceMappingParser;
+        _logger = logger;
         _mappings = null;
     }
 
@@ -103,6 +107,15 @@ public void UpdateDependencyVersion(VmrDependencyUpdate update)
             update.BarId);
         _fileSystem.WriteToFile(_vmrInfo.SourceManifestPath, _sourceManifest.ToJson());
 
+        var gitInfoDirPath = _vmrInfo.VmrPath / VmrInfo.GitInfoSourcesDir;
+        
+        // Only update git-info files if the git-info directory exists
+        if (!_fileSystem.DirectoryExists(gitInfoDirPath))
+        {
+            _logger.LogInformation("Skipped creating git-info files for {repo} as the git-info directory doesn't exist", update.Mapping.Name);
+            return;
+        }
+            
         // Root repository of an update does not have a package version associated with it
         // For installer, we leave whatever was there (e.g. 8.0.100)
         // For one-off non-recursive updates of repositories, we keep the previous
@@ -125,13 +138,24 @@ public void UpdateDependencyVersion(VmrDependencyUpdate update)
             OutputPackageVersion = packageVersion,
         };
 
-        gitInfo.SerializeToXml(GetGitInfoFilePath(update.Mapping));
+        var gitInfoFilePath = GetGitInfoFilePath(update.Mapping);
+        gitInfo.SerializeToXml(gitInfoFilePath);
+        _logger.LogInformation("Updated git-info file {file} for {repo}", gitInfoFilePath, update.Mapping.Name);
     }
 
     public bool RemoveRepositoryVersion(string repo)
     {
         var hasChanges = false;
 
+        var gitInfoDirPath = _vmrInfo.VmrPath / VmrInfo.GitInfoSourcesDir;
+        
+        // Only try to delete git-info files if the git-info directory exists
+        if (!_fileSystem.DirectoryExists(gitInfoDirPath))
+        {
+            _logger.LogInformation("Skipped removing git-info file for {repo} as the git-info directory doesn't exist", repo);
+            return hasChanges;
+        }
+            
         var gitInfoFilePath = GetGitInfoFilePath(repo);
         if (_fileSystem.FileExists(gitInfoFilePath))
         {

src/Microsoft.DotNet.Darc/DarcLib/VirtualMonoRepo/VmrManagerBase.cs

@@ -109,9 +109,15 @@ protected async Task<IReadOnlyCollection<VmrIngestionPatch>> UpdateRepoToRevisio
 
         var filesToAdd = new List<string>
         {
-            VmrInfo.GitInfoSourcesDir,
             _vmrInfo.SourceManifestPath
         };
+        
+        // Only add the git-info directory to staging if it exists
+        var gitInfoDirPath = _vmrInfo.VmrPath / VmrInfo.GitInfoSourcesDir;
+        if (_fileSystem.DirectoryExists(gitInfoDirPath))
+        {
+            filesToAdd.Add(VmrInfo.GitInfoSourcesDir);
+        }
 
         await _localGitClient.StageAsync(_vmrInfo.VmrPath, filesToAdd, cancellationToken);
 

test/Microsoft.DotNet.Darc.VirtualMonoRepo.E2E.Tests/VmrSyncAdditionalMappingsTest.cs

@@ -3,6 +3,7 @@
 
 using System.Collections.Generic;
 using System.IO;
+using System.Linq;
 using System.Threading.Tasks;
 using Microsoft.DotNet.DarcLib.Helpers;
 using Microsoft.DotNet.DarcLib.Models.VirtualMonoRepo;
@@ -22,7 +23,6 @@ internal class VmrSyncAdditionalMappingsTest : VmrTestsBase
     public async Task NonSrcContentIsSyncedTest()
     {
         // Initialize the repo
-
         await InitializeRepoAtLastCommit(Constants.ProductRepoName, ProductRepoPath);
 
         var expectedFilesFromRepos = new List<NativePath>
@@ -38,6 +38,9 @@ public async Task NonSrcContentIsSyncedTest()
             expectedFilesFromRepos
         );
 
+        // The git-info files are not created in this test so we should not expect them
+        expectedFiles = [..expectedFiles.Where(f => !f.Path.Contains(new NativePath(VmrInfo.GitInfoSourcesDir)))];
+
         CheckDirectoryContents(VmrPath, expectedFiles);
         await GitOperations.CheckAllIsCommitted(VmrPath);
 
@@ -69,6 +72,9 @@ protected override async Task CopyVmrForCurrentTest()
     {
         CopyDirectory(VmrTestsOneTimeSetUp.CommonVmrPath, VmrPath);
 
+        // In this test, we remove the git-info directory to see that it does not get created
+        Directory.Delete(VmrPath / "prereqs" / "git-info");
+
         var sourceMappings = new SourceMappingFile()
         {
             Mappings =

test/Microsoft.DotNet.Darc.VirtualMonoRepo.E2E.Tests/VmrTestsBase.cs

@@ -63,6 +63,10 @@ public async Task Setup()
 
         await CopyReposForCurrentTest();
         await CopyVmrForCurrentTest();
+        
+        // Ensure git-info directory exists for tests
+        Directory.CreateDirectory(VmrPath / "prereqs");
+        Directory.CreateDirectory(VmrPath / "prereqs" / "git-info");
 
         ServiceProvider = CreateServiceProvider().BuildServiceProvider();
         ServiceProvider.GetRequiredService<IVmrInfo>().VmrUri = VmrPath;

test/Microsoft.DotNet.Darc.VirtualMonoRepo.E2E.Tests/VmrTestsOneTimeSetUp.cs

@@ -45,6 +45,7 @@ public async Task OneTimeSetUp()
 
         Directory.CreateDirectory(TestsDirectory / Constants.VmrName);
         Directory.CreateDirectory(TestsDirectory / Constants.VmrName / VmrInfo.SourcesDir);
+        Directory.CreateDirectory(TestsDirectory / Constants.VmrName / VmrInfo.GitInfoSourcesDir);
         await _gitOperations.InitialCommit(TestsDirectory / Constants.VmrName);
 
         await CreateRepository(CommonProductRepoPath, Constants.ProductRepoName, Constants.GetRepoFileName(Constants.ProductRepoName));