fix(switch): resolve main worktree path from worktree list instead of repo root (#79)

GetRepoRoot() uses `git rev-parse --show-toplevel` which returns the
current worktree's root, not the main repo root. This caused `ss main`
to resolve to the wrong path when run from a worktree.

Use `git worktree list` for all branches uniformly, which always returns
the correct path.

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

Author: javoire

cmd/switch.go

@@ -98,17 +98,6 @@ func runSwitch(gitClient git.GitClient, branchName string) error {
 }
 
 func resolveWorktreePath(gitClient git.GitClient, branchName string) (string, error) {
-	// Check if it's the base branch
-	baseBranch := stack.GetBaseBranch(gitClient)
-	if branchName == baseBranch {
-		repoRoot, err := gitClient.GetRepoRoot()
-		if err != nil {
-			return "", fmt.Errorf("failed to get repo root: %w", err)
-		}
-		return repoRoot, nil
-	}
-
-	// Look up in worktree branches
 	worktreeBranches, err := gitClient.GetWorktreeBranches()
 	if err != nil {
 		return "", fmt.Errorf("failed to get worktree branches: %w", err)
@@ -150,18 +139,16 @@ func runSwitchInteractive(gitClient git.GitClient) error {
 	}
 	var options []option
 
-	// Add main repo
+	// Add main repo (base branch from worktree list)
 	baseBranch := stack.GetBaseBranch(gitClient)
-	repoRoot, err := gitClient.GetRepoRoot()
-	if err != nil {
-		return fmt.Errorf("failed to get repo root: %w", err)
+	if path, ok := worktreeBranches[baseBranch]; ok {
+		options = append(options, option{branch: baseBranch, path: path})
 	}
-	options = append(options, option{branch: baseBranch, path: repoRoot})
 
 	// Add worktrees filtered to this repo's worktrees dir
 	var sortedBranches []string
 	for branch, path := range worktreeBranches {
-		if pathWithinDir(path, worktreesDir) {
+		if branch != baseBranch && pathWithinDir(path, worktreesDir) {
 			sortedBranches = append(sortedBranches, branch)
 		}
 	}

cmd/switch_test.go

@@ -17,8 +17,6 @@ func TestRunSwitch(t *testing.T) {
 	t.Run("resolves worktree branch to path", func(t *testing.T) {
 		mockGit := new(testutil.MockGitClient)
 
-		mockGit.On("GetConfig", "stack.baseBranch").Return("")
-		mockGit.On("GetDefaultBranch").Return("main")
 		mockGit.On("GetWorktreeBranches").Return(map[string]string{
 			"feature-a": "/home/user/.stack/worktrees/repo/feature-a",
 			"feature-b": "/home/user/.stack/worktrees/repo/feature-b",
@@ -41,12 +39,13 @@ func TestRunSwitch(t *testing.T) {
 		mockGit.AssertExpectations(t)
 	})
 
-	t.Run("resolves base branch to repo root", func(t *testing.T) {
+	t.Run("resolves base branch to main repo via worktree list", func(t *testing.T) {
 		mockGit := new(testutil.MockGitClient)
 
-		mockGit.On("GetConfig", "stack.baseBranch").Return("")
-		mockGit.On("GetDefaultBranch").Return("main")
-		mockGit.On("GetRepoRoot").Return("/home/user/code/repo", nil)
+		mockGit.On("GetWorktreeBranches").Return(map[string]string{
+			"main":      "/home/user/code/repo",
+			"feature-a": "/home/user/.stack/worktrees/repo/feature-a",
+		}, nil)
 
 		old := os.Stdout
 		r, w, _ := os.Pipe()
@@ -67,8 +66,6 @@ func TestRunSwitch(t *testing.T) {
 	t.Run("errors for unknown branch", func(t *testing.T) {
 		mockGit := new(testutil.MockGitClient)
 
-		mockGit.On("GetConfig", "stack.baseBranch").Return("")
-		mockGit.On("GetDefaultBranch").Return("main")
 		mockGit.On("GetWorktreeBranches").Return(map[string]string{}, nil)
 
 		err := runSwitch(mockGit, "nonexistent")