navigation commands

Author: skarim

cmd/navigate.go

@@ -0,0 +1,189 @@
+package cmd
+
+import (
+	"fmt"
+
+	"github.com/github/gh-stack/internal/config"
+	"github.com/github/gh-stack/internal/git"
+	"github.com/github/gh-stack/internal/stack"
+	"github.com/spf13/cobra"
+)
+
+func UpCmd(cfg *config.Config) *cobra.Command {
+	return &cobra.Command{
+		Use:   "up [n]",
+		Short: "Move up in the stack (toward the top)",
+		Args:  cobra.MaximumNArgs(1),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			n := 1
+			if len(args) > 0 {
+				fmt.Sscanf(args[0], "%d", &n)
+			}
+			return runNavigate(cfg, n)
+		},
+	}
+}
+
+func DownCmd(cfg *config.Config) *cobra.Command {
+	return &cobra.Command{
+		Use:   "down [n]",
+		Short: "Move down in the stack (toward the trunk)",
+		Args:  cobra.MaximumNArgs(1),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			n := 1
+			if len(args) > 0 {
+				fmt.Sscanf(args[0], "%d", &n)
+			}
+			return runNavigate(cfg, -n)
+		},
+	}
+}
+
+func TopCmd(cfg *config.Config) *cobra.Command {
+	return &cobra.Command{
+		Use:   "top",
+		Short: "Move to the top of the stack",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return runNavigateToEnd(cfg, true)
+		},
+	}
+}
+
+func BottomCmd(cfg *config.Config) *cobra.Command {
+	return &cobra.Command{
+		Use:   "bottom",
+		Short: "Move to the bottom of the stack",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return runNavigateToEnd(cfg, false)
+		},
+	}
+}
+
+func runNavigate(cfg *config.Config, delta int) error {
+	s, currentBranch, err := loadCurrentStack(cfg)
+	if err != nil {
+		return nil
+	}
+
+	idx := s.IndexOf(currentBranch)
+	if idx < 0 {
+		// Might be on the trunk
+		if currentBranch == s.Trunk.Branch {
+			if delta > 0 && len(s.Branches) > 0 {
+				target := s.Branches[0].Branch
+				if err := git.CheckoutBranch(target); err != nil {
+					return err
+				}
+				cfg.Successf("Switched to %s", target)
+				return nil
+			}
+			cfg.Printf("already at the bottom of the stack")
+			return nil
+		}
+		cfg.Errorf("current branch %q is not in the stack", currentBranch)
+		return nil
+	}
+
+	newIdx := idx + delta
+	if newIdx < 0 {
+		newIdx = 0
+	}
+	if newIdx >= len(s.Branches) {
+		newIdx = len(s.Branches) - 1
+	}
+
+	if newIdx == idx {
+		if delta > 0 {
+			cfg.Printf("Already at the top of the stack")
+		} else {
+			cfg.Printf("Already at the bottom of the stack")
+		}
+		return nil
+	}
+
+	target := s.Branches[newIdx].Branch
+	if err := git.CheckoutBranch(target); err != nil {
+		return err
+	}
+
+	moved := newIdx - idx
+	direction := "up"
+	if moved < 0 {
+		direction = "down"
+		moved = -moved
+	}
+
+	cfg.Successf("Moved %s %d %s to %s", direction, moved, plural(moved, "branch", "branches"), target)
+	return nil
+}
+
+func runNavigateToEnd(cfg *config.Config, top bool) error {
+	s, currentBranch, err := loadCurrentStack(cfg)
+	if err != nil {
+		cfg.Errorf("failed to load current stack: %s", err)
+		return nil
+	}
+
+	var target string
+	if top {
+		target = s.Branches[len(s.Branches)-1].Branch
+	} else {
+		target = s.Branches[0].Branch
+	}
+
+	if target == currentBranch {
+		if top {
+			cfg.Printf("Already at the top of the stack")
+		} else {
+			cfg.Printf("Already at the bottom of the stack")
+		}
+		return nil
+	}
+
+	if err := git.CheckoutBranch(target); err != nil {
+		return err
+	}
+
+	cfg.Successf("Switched to %s", target)
+	return nil
+}
+
+func loadCurrentStack(cfg *config.Config) (*stack.Stack, string, error) {
+	gitDir, err := git.GitDir()
+	if err != nil {
+		errMsg := "not a git repository"
+		cfg.Errorf("%s", errMsg)
+		return nil, "", fmt.Errorf("%s", errMsg)
+	}
+
+	sf, err := stack.Load(gitDir)
+	if err != nil {
+		errMsg := fmt.Sprintf("failed to load stack state: %s", err)
+		cfg.Errorf("%s", errMsg)
+		return nil, "", fmt.Errorf("%s", errMsg)
+	}
+
+	currentBranch, err := git.CurrentBranch()
+	if err != nil {
+		errMsg := fmt.Sprintf("failed to get current branch: %s", err)
+		cfg.Errorf("%s", errMsg)
+		return nil, "", fmt.Errorf("%s", errMsg)
+	}
+
+	s := sf.FindStackForBranch(currentBranch)
+	if s == nil {
+		errMsg := fmt.Sprintf("current branch %q is not part of a stack", currentBranch)
+		cfg.Errorf("current branch %q is not part of a stack", currentBranch)
+		cfg.Printf("Checkout an existing stack using %s or create a new stack using %s", cfg.ColorCyan("gh stack checkout"), cfg.ColorCyan("gh stack init"))
+		return nil, "", fmt.Errorf("%s", errMsg)
+	}
+
+	return s, currentBranch, nil
+}
+
+func plural(n int, singular, pluralForm string) string {
+	if n == 1 {
+		return singular
+	}
+	return pluralForm
+}

cmd/root.go

@@ -27,6 +27,10 @@ func RootCmd() *cobra.Command {
 
 	// Helper commands
 	root.AddCommand(ViewCmd(cfg))
+	root.AddCommand(UpCmd(cfg))
+	root.AddCommand(DownCmd(cfg))
+	root.AddCommand(TopCmd(cfg))
+	root.AddCommand(BottomCmd(cfg))
 
 	// Placeholders for upcoming features
 	for _, ph := range placeholderCommands {