feat: add stack config command

README.md

@@ -90,6 +90,21 @@ See [Commands Reference](docs/commands.md) for full documentation.
 - `stack reparent <new-parent>` - Change the parent of the current branch
 - `stack worktree <branch-name>` - Create a worktree for a branch
 
+## Configuration
+
+Configure the base branch and worktrees directory with git config:
+
+```bash
+git config stack.baseBranch develop  # Default is "main"
+git config stack.worktreesDir ~/worktrees
+```
+
+Or use the interactive helper:
+
+```bash
+stack config set
+```
+
 ## Documentation
 
 - [How It Works](docs/how-it-works.md) - Stack tracking and sync algorithm

cmd/config.go

@@ -0,0 +1,131 @@
+package cmd
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"github.com/javoire/stackinator/internal/git"
+	"github.com/javoire/stackinator/internal/ui"
+	"github.com/spf13/cobra"
+)
+
+var configStdin io.Reader = os.Stdin
+
+var configCmd = &cobra.Command{
+	Use:   "config",
+	Short: "Show stackinator configuration for this repository",
+	Long: `Show stackinator configuration for this repository.
+
+Use 'stack config set' to update settings.`,
+	Run: func(cmd *cobra.Command, args []string) {
+		gitClient := git.NewGitClient()
+		if err := runConfigShow(gitClient); err != nil {
+			fmt.Fprintf(os.Stderr, "Error: %v\n", err)
+			os.Exit(1)
+		}
+	},
+}
+
+var configGetCmd = &cobra.Command{
+	Use:   "get",
+	Short: "Show stackinator configuration for this repository",
+	Run: func(cmd *cobra.Command, args []string) {
+		gitClient := git.NewGitClient()
+		if err := runConfigShow(gitClient); err != nil {
+			fmt.Fprintf(os.Stderr, "Error: %v\n", err)
+			os.Exit(1)
+		}
+	},
+}
+
+var configSetCmd = &cobra.Command{
+	Use:   "set",
+	Short: "Interactively configure stackinator settings",
+	Long: `Interactively configure stackinator settings.
+
+Currently supports the worktrees directory location.`,
+	Run: func(cmd *cobra.Command, args []string) {
+		gitClient := git.NewGitClient()
+		if err := runConfigSet(gitClient); err != nil {
+			fmt.Fprintf(os.Stderr, "Error: %v\n", err)
+			os.Exit(1)
+		}
+	},
+}
+
+func init() {
+	configCmd.AddCommand(configGetCmd)
+	configCmd.AddCommand(configSetCmd)
+}
+
+func runConfigShow(gitClient git.GitClient) error {
+	configured := strings.TrimSpace(gitClient.GetConfig("stack.worktreesDir"))
+	if configured == "" {
+		configured = "(default)"
+	}
+
+	effective, err := getWorktreesBaseDir(gitClient)
+	if err != nil {
+		return err
+	}
+
+	fmt.Println("Worktrees directory:")
+	fmt.Printf("  Configured: %s\n", configured)
+	fmt.Printf("  Effective:  %s\n", effective)
+
+	return nil
+}
+
+func runConfigSet(gitClient git.GitClient) error {
+	defaultDir, err := getDefaultWorktreesBaseDir()
+	if err != nil {
+		return err
+	}
+
+	repoRoot, err := gitClient.GetRepoRoot()
+	if err != nil {
+		return err
+	}
+
+	projectDir := filepath.Join(repoRoot, ".worktrees")
+
+	fmt.Println("Choose worktrees directory:")
+	fmt.Printf("  1) %s (default)\n", defaultDir)
+	fmt.Printf("  2) %s (this repo)\n", projectDir)
+	fmt.Printf("Select [1/2] (default 1): ")
+
+	reader := bufio.NewReader(configStdin)
+	input, err := reader.ReadString('\n')
+	if err != nil {
+		return fmt.Errorf("failed to read input: %w", err)
+	}
+
+	choice := strings.TrimSpace(input)
+	if choice == "" {
+		choice = "1"
+	}
+
+	var configValue string
+	switch choice {
+	case "1":
+		configValue = "~/.stack/worktrees"
+	case "2":
+		configValue = ".worktrees"
+	default:
+		return fmt.Errorf("invalid selection: %s", choice)
+	}
+
+	if err := gitClient.SetConfig("stack.worktreesDir", configValue); err != nil {
+		return fmt.Errorf("failed to set worktrees directory: %w", err)
+	}
+
+	if !dryRun {
+		fmt.Println(ui.Success(fmt.Sprintf("Worktrees directory set to %s", configValue)))
+	}
+
+	return nil
+}

cmd/config_test.go

@@ -0,0 +1,123 @@
+package cmd
+
+import (
+	"errors"
+	"strings"
+	"testing"
+
+	"github.com/javoire/stackinator/internal/testutil"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestGetWorktreesBaseDir(t *testing.T) {
+	t.Setenv("HOME", "/home/test")
+
+	tests := []struct {
+		name     string
+		config   string
+		repoRoot string
+		repoErr  error
+		expected string
+	}{
+		{
+			name:     "default when no config",
+			config:   "",
+			repoRoot: "/repo",
+			expected: "/home/test/.stack/worktrees",
+		},
+		{
+			name:     "tilde expands",
+			config:   "~/worktrees",
+			repoRoot: "/repo",
+			expected: "/home/test/worktrees",
+		},
+		{
+			name:     "env expands",
+			config:   "$HOME/custom",
+			repoRoot: "/repo",
+			expected: "/home/test/custom",
+		},
+		{
+			name:     "relative uses repo root",
+			config:   ".worktrees",
+			repoRoot: "/repo",
+			expected: "/repo/.worktrees",
+		},
+		{
+			name:     "relative falls back to home when repo root missing",
+			config:   ".worktrees",
+			repoErr:  errors.New("no repo"),
+			expected: "/home/test/.worktrees",
+		},
+		{
+			name:     "absolute kept as is",
+			config:   "/abs/worktrees",
+			repoRoot: "/repo",
+			expected: "/abs/worktrees",
+		},
+	}
+
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			mockGit := &testutil.MockGitClient{}
+			mockGit.On("GetRepoRoot").Return(tt.repoRoot, tt.repoErr)
+			mockGit.On("GetConfig", "stack.worktreesDir").Return(tt.config)
+
+			dir, err := getWorktreesBaseDir(mockGit)
+			assert.NoError(t, err)
+			assert.Equal(t, tt.expected, dir)
+			mockGit.AssertExpectations(t)
+		})
+	}
+}
+
+func TestRunConfigSet(t *testing.T) {
+	t.Setenv("HOME", "/home/test")
+
+	tests := []struct {
+		name        string
+		input       string
+		expectValue string
+		expectErr   bool
+	}{
+		{
+			name:        "default selection",
+			input:       "\n",
+			expectValue: "~/.stack/worktrees",
+		},
+		{
+			name:        "select repo local",
+			input:       "2\n",
+			expectValue: ".worktrees",
+		},
+		{
+			name:      "invalid selection",
+			input:     "3\n",
+			expectErr: true,
+		},
+	}
+
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			mockGit := &testutil.MockGitClient{}
+			mockGit.On("GetRepoRoot").Return("/repo", nil)
+			if !tt.expectErr {
+				mockGit.On("SetConfig", "stack.worktreesDir", tt.expectValue).Return(nil)
+			}
+
+			previousStdin := configStdin
+			configStdin = strings.NewReader(tt.input)
+			defer func() { configStdin = previousStdin }()
+
+			err := runConfigSet(mockGit)
+			if tt.expectErr {
+				assert.Error(t, err)
+			} else {
+				assert.NoError(t, err)
+			}
+			mockGit.AssertExpectations(t)
+		})
+	}
+}

cmd/root.go

@@ -78,6 +78,7 @@ func init() {
 	rootCmd.AddCommand(renameCmd)
 	rootCmd.AddCommand(reparentCmd)
 	rootCmd.AddCommand(worktreeCmd)
+	rootCmd.AddCommand(configCmd)
 	rootCmd.AddCommand(upCmd)
 	rootCmd.AddCommand(downCmd)
 }