fix: preserve group name when promoting to local folder group

PolyPilot.Tests/SessionOrganizationTests.cs

@@ -933,6 +933,105 @@ public void PromoteOrCreateLocalFolderGroup_PromotesMostRecentUrlGroup_WhenMulti
         Assert.False(olderGroup!.IsLocalFolder);  // older group stays URL-based
     }
 
+    [Fact]
+    public void PromoteOrCreateLocalFolderGroup_PreservesUserGroupName_WhenFolderNameDiffers()
+    {
+        // Regression test: when the user's group is named "maui" and the local folder
+        // is "~/Projects/maui2", promotion must NOT rename the group to "maui2".
+        var svc = CreateService();
+        // Note: path need not exist on disk; promotion matches on repoId, not disk state.
+        var localRepoPath = Path.Combine(Path.GetTempPath(), "maui2");
+        var expectedPath = Path.GetFullPath(localRepoPath)
+            .TrimEnd(Path.DirectorySeparatorChar, Path.AltDirectorySeparatorChar);
+
+        // Simulate: user has a group named "maui" for repo "dotnet-maui"
+        var urlGroup = svc.GetOrCreateRepoGroup("dotnet-maui", "maui");
+        Assert.NotNull(urlGroup);
+        Assert.Equal("maui", urlGroup!.Name);
+
+        // Promote with a folder whose basename is "maui2" — NOT "maui"
+        var result = svc.PromoteOrCreateLocalFolderGroup(localRepoPath, "dotnet-maui");
+
+        Assert.Equal(urlGroup.Id, result.Id);
+        Assert.True(result.IsLocalFolder);
+        Assert.Equal(expectedPath, result.LocalPath);
+        // Name must be preserved — NOT overwritten with "maui2"
+        Assert.Equal("maui", result.Name);
+    }
+
+    [Fact]
+    public void ReconcileOrganization_ExternalWorktree_PreservesGroupName_WhenPromoting()
+    {
+        // Regression test: ReconcileOrganization's external worktree migration must
+        // preserve the group's name when promoting it to a local folder group.
+        var repos = new List<RepositoryInfo>
+        {
+            new() { Id = "dotnet-maui", Name = "maui", Url = "https://github.com/dotnet/maui" }
+        };
+        // External worktree folder name is "maui2" — differs from group name "maui"
+        // Note: path need not exist on disk; ReconcileOrganization matches on repoId, not disk state.
+        var extPath = Path.Combine(Path.GetTempPath(), "maui2");
+        var worktrees = new List<WorktreeInfo>
+        {
+            new() { Id = "ext-1", RepoId = "dotnet-maui", Branch = "main", Path = extPath }
+        };
+        var rm = CreateRepoManagerWithState(repos, worktrees);
+        var svc = CreateService(rm);
+
+        // Create a URL-based group named "maui" (user's custom name)
+        var urlGroup = svc.GetOrCreateRepoGroup("dotnet-maui", "maui");
+        Assert.Equal("maui", urlGroup!.Name);
+
+        svc.ReconcileOrganization();
+
+        var promoted = svc.Organization.Groups.First(g => g.Id == urlGroup.Id);
+        Assert.True(promoted.IsLocalFolder);
+        // Name must be "maui" — NOT "maui2" (the folder basename)
+        Assert.Equal("maui", promoted.Name);
+    }
+
+    [Fact]
+    public void PromoteOrCreateLocalFolderGroup_CreationPath_UsesFolderBasename()
+    {
+        // Documents intentional asymmetry: when no URL group exists to promote,
+        // the creation path names the group after the folder basename.
+        // This differs from promotion (which preserves the existing group name).
+        var svc = CreateService();
+        // Note: path need not exist on disk; creation matches on repoId, not disk state.
+        var localRepoPath = Path.Combine(Path.GetTempPath(), "my-project");
+        var expectedName = "my-project";
+
+        // No existing group for "new-repo" — creation path will be used
+        var result = svc.PromoteOrCreateLocalFolderGroup(localRepoPath, "new-repo");
+
+        Assert.True(result.IsLocalFolder);
+        Assert.Equal(expectedName, result.Name);
+    }
+
+    [Fact]
+    public void PromoteOrCreateLocalFolderGroup_FallsBackToFolderName_WhenGroupNameIsEmpty()
+    {
+        // Defensive: if a promotable group has an empty name (corrupt state),
+        // promotion falls back to the folder basename instead of preserving blank.
+        var svc = CreateService();
+        var localRepoPath = Path.Combine(Path.GetTempPath(), "fallback-name");
+        var expectedPath = Path.GetFullPath(localRepoPath)
+            .TrimEnd(Path.DirectorySeparatorChar, Path.AltDirectorySeparatorChar);
+
+        // Create a URL group and then blank out its name to simulate corrupt state
+        var urlGroup = svc.GetOrCreateRepoGroup("corrupt-repo", "original");
+        Assert.NotNull(urlGroup);
+        urlGroup!.Name = "";
+
+        var result = svc.PromoteOrCreateLocalFolderGroup(localRepoPath, "corrupt-repo");
+
+        Assert.Equal(urlGroup.Id, result.Id);
+        Assert.True(result.IsLocalFolder);
+        Assert.Equal(expectedPath, result.LocalPath);
+        // Empty name should be repaired with the folder basename
+        Assert.Equal("fallback-name", result.Name);
+    }
+
     [Fact]
     public void ReconcileOrganization_ExternalWorktree_PromotesUrlGroupToLocalFolderGroup()
     {

PolyPilot/Services/CopilotService.Organization.cs

@@ -741,9 +741,14 @@ internal void ReconcileOrganization(bool allowPruning = true)
             if (groupToPromote != null)
             {
                 groupToPromote.LocalPath = normalizedExtPath;
-                groupToPromote.Name = Path.GetFileName(normalizedExtPath);
+                // Preserve the user's group name — don't overwrite with the folder basename.
+                // The old code did: groupToPromote.Name = Path.GetFileName(normalizedExtPath)
+                // which destroyed user-customized names (e.g., "maui" → "maui2").
+                // Fallback: if the group somehow has an empty name, use the folder basename.
+                if (string.IsNullOrWhiteSpace(groupToPromote.Name))
+                    groupToPromote.Name = Path.GetFileName(normalizedExtPath);
                 changed = true;
-                Debug($"ReconcileOrganization: promoted group '{groupToPromote.Id}' to local folder group for '{normalizedExtPath}'");
+                Debug($"ReconcileOrganization: promoted group '{groupToPromote.Id}' ('{groupToPromote.Name}') to local folder group for '{normalizedExtPath}'");
 
                 // Migrate sessions whose worktrees are NOT under the new LocalPath to the
                 // URL-based repo group. Without this, sessions linked to managed worktrees
@@ -1533,15 +1538,24 @@ public SessionGroup PromoteOrCreateLocalFolderGroup(string localPath, string? re
             if (candidate != null)
             {
                 candidate.LocalPath = normalized;
-                candidate.Name = Path.GetFileName(normalized);
+                // Preserve the user's group name — don't overwrite with the folder basename.
+                // The old code did: candidate.Name = Path.GetFileName(normalized)
+                // which destroyed user-customized names (e.g., "maui" → "maui2").
+                // Fallback: if the group somehow has an empty name, use the folder basename.
+                if (string.IsNullOrWhiteSpace(candidate.Name))
+                    candidate.Name = Path.GetFileName(normalized);
                 SaveOrganization();
                 OnStateChanged?.Invoke();
-                Debug($"PromoteOrCreateLocalFolderGroup: promoted '{candidate.Id}' to local folder group for '{normalized}'");
+                Debug($"PromoteOrCreateLocalFolderGroup: promoted '{candidate.Id}' ('{candidate.Name}') to local folder group for '{normalized}'");
                 return candidate;
             }
         }
 
         // No existing group to promote — create a fresh local folder group.
+        // Note: the creation path uses Path.GetFileName(localPath) as the group name,
+        // which differs from promotion (which preserves the existing name). This is
+        // intentional: new groups get a sensible default from the folder name, while
+        // existing groups keep whatever the user (or auto-creation) named them.
         return GetOrCreateLocalFolderGroup(localPath, repoId);
     }