fix: preserve terminal stderr for ticket pickers

e2e/ticket_terminal_test.go

@@ -0,0 +1,86 @@
+//go:build darwin || linux
+
+package e2e
+
+import (
+	"context"
+	"io"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+	"syscall"
+	"testing"
+	"time"
+
+	"github.com/creack/pty"
+)
+
+func TestREV010_TicketPickerInheritsTerminalWithoutShellRedirection(t *testing.T) {
+	s := newSandbox(t)
+	repo := s.repo()
+	herdr := s.fakeHerdr(repo)
+	s.tool("tickets", `
+[ -t 0 ] && [ -t 2 ] || { printf 'picker needs terminal stdin/stderr\n' >&2; exit 2; }
+size=$(/bin/stty size <&2)
+[ "$size" = '30 100' ] || { printf 'incorrect dimensions: %s\n' "$size" >&2; exit 2; }
+printf 'PICKER_READY %s\n' "$size" >&2
+IFS= read -r selection
+[ "$selection" = select ] || exit 23
+printf '%s\n' '{"branchName":"test-123-selected","metadata":{"identifier":"TEST-123"}}'
+`)
+	mustWrite(t, filepath.Join(repo, ".herdr-worktree.yaml"), "ticket_commands:\n  default:\n    command: [tickets, '{input}']\n", 0o600)
+	master, slave, err := pty.Open()
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer slave.Close()
+	fd, err := syscall.Dup(int(master.Fd()))
+	_ = master.Close()
+	if err != nil {
+		t.Fatal(err)
+	}
+	syscall.CloseOnExec(fd)
+	if err := syscall.SetNonblock(fd, true); err != nil {
+		_ = syscall.Close(fd)
+		t.Fatal(err)
+	}
+	master = os.NewFile(uintptr(fd), "ticket-pty")
+	defer master.Close()
+	if err := master.SetReadDeadline(time.Now().Add(15 * time.Second)); err != nil {
+		t.Fatal(err)
+	}
+	if err := pty.Setsize(slave, &pty.Winsize{Rows: 30, Cols: 100}); err != nil {
+		t.Fatal(err)
+	}
+	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+	defer cancel()
+	cmd := exec.CommandContext(ctx, hwtBinary, "--herdr-bin", herdr, "create", "--ticket", "--json")
+	cmd.Dir, cmd.Env = repo, s.env
+	cmd.Stdin, cmd.Stderr = slave, slave
+	cmd.SysProcAttr = &syscall.SysProcAttr{Setpgid: true}
+	cmd.Cancel = func() error { return syscall.Kill(-cmd.Process.Pid, syscall.SIGKILL) }
+	cmd.WaitDelay = time.Second
+	var stdout strings.Builder
+	cmd.Stdout = &stdout
+	// This canonical-mode input is buffered until the fake picker reads it.
+	if _, err := io.WriteString(master, "select\n"); err != nil {
+		t.Fatal(err)
+	}
+	if err := cmd.Run(); err != nil {
+		t.Fatalf("ticket create failed: %v; stdout: %s", err, stdout.String())
+	}
+	result := decode(t, stdout.String())
+	if result["branch"] != "test-123-selected" {
+		t.Fatalf("selected branch = %#v", result)
+	}
+	gitDir := s.git(result["path"].(string), "rev-parse", "--git-dir")
+	metadata := mustRead(t, filepath.Join(gitDir, "hwt-ticket-metadata-v1.json"))
+	requireContains(t, metadata, "TEST-123")
+	ui := make([]byte, 4096)
+	n, err := master.Read(ui)
+	if err != nil {
+		t.Fatal(err)
+	}
+	requireContains(t, string(ui[:n]), "PICKER_READY 30 100")
+}

go.mod

@@ -5,6 +5,8 @@ go 1.25.0
 require (
 	charm.land/bubbletea/v2 v2.0.8
 	charm.land/lipgloss/v2 v2.0.5
+	github.com/charmbracelet/x/term v0.2.2
+	github.com/creack/pty v1.1.24
 	github.com/spf13/cobra v1.10.2
 	go.yaml.in/yaml/v3 v3.0.4
 	golang.org/x/sys v0.47.0
@@ -14,7 +16,6 @@ require (
 	github.com/charmbracelet/colorprofile v0.4.3 // indirect
 	github.com/charmbracelet/ultraviolet v0.0.0-20260703014108-f5a850f9c2b7 // indirect
 	github.com/charmbracelet/x/ansi v0.11.7 // indirect
-	github.com/charmbracelet/x/term v0.2.2 // indirect
 	github.com/charmbracelet/x/termios v0.1.1 // indirect
 	github.com/charmbracelet/x/windows v0.2.2 // indirect
 	github.com/clipperhouse/displaywidth v0.11.0 // indirect

go.sum

@@ -23,6 +23,8 @@ github.com/clipperhouse/displaywidth v0.11.0/go.mod h1:bkrFNkf81G8HyVqmKGxsPufD3
 github.com/clipperhouse/uax29/v2 v2.7.0 h1:+gs4oBZ2gPfVrKPthwbMzWZDaAFPGYK72F0NJv2v7Vk=
 github.com/clipperhouse/uax29/v2 v2.7.0/go.mod h1:EFJ2TJMRUaplDxHKj1qAEhCtQPW2tJSwu5BF98AuoVM=
 github.com/cpuguy83/go-md2man/v2 v2.0.6/go.mod h1:oOW0eioCTA6cOiMLiUPZOpcVxMig6NIQQ7OS05n1F4g=
+github.com/creack/pty v1.1.24 h1:bJrF4RRfyJnbTJqzRLHzcGaZK1NeM5kTC9jGgovnR1s=
+github.com/creack/pty v1.1.24/go.mod h1:08sCNb52WyoAwi2QDyzUCTgcvVFhUzewun7wtTfvcwE=
 github.com/inconshreveable/mousetrap v1.1.0 h1:wN+x4NVGpMsO7ErUn/mUI3vEoE6Jt13X2s0bqwp9tc8=
 github.com/inconshreveable/mousetrap v1.1.0/go.mod h1:vpF70FUmC8bwa3OWnCshd2FqLfsEA9PFc4w1p2J65bw=
 github.com/lucasb-eyer/go-colorful v1.4.0 h1:UtrWVfLdarDgc44HcS7pYloGHJUjHV/4FwW4TvVgFr4=

internal/worktree/ticket_command.go

@@ -10,6 +10,7 @@ import (
 	"os/exec"
 	"strings"
 
+	"github.com/charmbracelet/x/term"
 	"github.com/dkarter/hwt/internal/config"
 )
 
@@ -27,13 +28,24 @@ func runTicketCommandWithStderr(cwd string, ticket config.TicketCommand, input s
 	cmd.Stdin = os.Stdin
 	var stdout, stderr bytes.Buffer
 	cmd.Stdout = &stdout
-	cmd.Stderr = io.MultiWriter(terminalStderr, &stderr)
+	// exec.Cmd only inherits a file descriptor when the writer is an *os.File.
+	// Wrapping a terminal in MultiWriter creates a pipe instead, hiding terminal
+	// dimensions and preventing interactive pickers from rendering their UI.
+	terminalFile, isFile := terminalStderr.(*os.File)
+	interactiveStderr := isFile && term.IsTerminal(terminalFile.Fd())
+	if interactiveStderr {
+		cmd.Stderr = terminalFile
+	} else {
+		cmd.Stderr = io.MultiWriter(terminalStderr, &stderr)
+	}
 	if err := cmd.Run(); err != nil {
 		if errors.Is(err, exec.ErrNotFound) {
 			return ticketResult{}, fmt.Errorf("find ticket command %q: %w", ticket.Command[0], err)
 		}
 		message := ""
-		if strings.TrimSpace(stderr.String()) == "" {
+		// Terminal diagnostics have already been displayed and are not captured;
+		// only use stdout as a fallback when we know stderr was empty.
+		if !interactiveStderr && strings.TrimSpace(stderr.String()) == "" {
 			message = strings.TrimSpace(stdout.String())
 		}
 		if message != "" {

internal/worktree/ticket_command_pty_test.go

@@ -0,0 +1,209 @@
+//go:build darwin || linux
+
+package worktree
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"os"
+	"os/exec"
+	"strings"
+	"syscall"
+	"testing"
+	"time"
+
+	tea "charm.land/bubbletea/v2"
+	"github.com/charmbracelet/x/term"
+	"github.com/creack/pty"
+	"github.com/dkarter/hwt/internal/config"
+)
+
+// Exercise both subprocess boundaries: HWT inherits terminal stdin/stderr,
+// then launches a picker with captured JSON stdout and terminal UI on stderr.
+func TestRunTicketCommandInteractiveTerminal(t *testing.T) {
+	for _, test := range []struct {
+		name string
+		key  string
+		want string
+	}{
+		{name: "select", key: "\r", want: "feature/selected"},
+		{name: "cancel", key: "\x1b", want: "exit status 23"},
+	} {
+		t.Run(test.name, func(t *testing.T) {
+			master, slave, err := pty.Open()
+			if err != nil {
+				t.Fatal(err)
+			}
+			defer slave.Close()
+			// Register a nonblocking descriptor with Go's poller so deadlines
+			// and Close can interrupt the UI reader, including on Darwin.
+			fd, err := syscall.Dup(int(master.Fd()))
+			_ = master.Close()
+			if err != nil {
+				t.Fatal(err)
+			}
+			syscall.CloseOnExec(fd)
+			if err := syscall.SetNonblock(fd, true); err != nil {
+				_ = syscall.Close(fd)
+				t.Fatal(err)
+			}
+			master = os.NewFile(uintptr(fd), "picker-pty")
+			defer master.Close()
+			if err := pty.Setsize(slave, &pty.Winsize{Rows: 30, Cols: 100}); err != nil {
+				t.Fatal(err)
+			}
+			executable, err := os.Executable()
+			if err != nil {
+				t.Fatal(err)
+			}
+			ctx, cancel := context.WithTimeout(context.Background(), 15*time.Second)
+			defer cancel()
+			deadline, _ := ctx.Deadline()
+			if err := master.SetReadDeadline(deadline); err != nil {
+				t.Fatal(err)
+			}
+			cmd := exec.CommandContext(ctx, executable, "-test.run=^TestTicketPickerProcess$", "--", "transport")
+			cmd.SysProcAttr = &syscall.SysProcAttr{Setpgid: true}
+			// Cancel the picker as well as its transport parent on timeout.
+			cmd.Cancel = func() error { return syscall.Kill(-cmd.Process.Pid, syscall.SIGKILL) }
+			cmd.WaitDelay = 2 * time.Second
+			cmd.Stdin, cmd.Stderr = slave, slave
+			var stdout bytes.Buffer
+			cmd.Stdout = &stdout
+			if err := cmd.Start(); err != nil {
+				t.Fatal(err)
+			}
+			// Read while the UI runs; wait for the measured size before sending input.
+			uiDone := make(chan string, 1)
+			go func() {
+				var ui strings.Builder
+				buf := make([]byte, 4096)
+				sent := false
+				for {
+					n, err := master.Read(buf)
+					ui.Write(buf[:n])
+					if !sent && strings.Contains(ui.String(), "PICKER_READY 100x30") {
+						_, _ = io.WriteString(master, test.key)
+						sent = true
+					}
+					if err != nil {
+						uiDone <- ui.String()
+						return
+					}
+				}
+			}()
+			waitErr := cmd.Wait()
+			_ = slave.Close()
+			// Darwin PTYs need the master closed to unblock a read after slave exit.
+			_ = master.Close()
+			ui := <-uiDone
+			if waitErr != nil {
+				t.Fatalf("transport: %v; UI: %q; stdout: %q", waitErr, ui, stdout.String())
+			}
+			if !strings.Contains(ui, "PICKER_READY 100x30") {
+				t.Fatalf("picker did not receive terminal dimensions: %q", ui)
+			}
+			var result struct {
+				Branch   string            `json:"branch"`
+				Metadata map[string]string `json:"metadata"`
+				Error    string            `json:"error"`
+			}
+			if err := json.Unmarshal(stdout.Bytes(), &result); err != nil {
+				t.Fatalf("UI leaked into JSON stdout %q: %v", stdout.String(), err)
+			}
+			if test.name == "select" {
+				if result.Branch != test.want || result.Metadata["identifier"] != "TEST-123" || result.Error != "" {
+					t.Fatalf("selected result = %#v", result)
+				}
+			} else if !strings.Contains(result.Error, test.want) || result.Branch != "" {
+				t.Fatalf("cancellation result = %#v", result)
+			}
+		})
+	}
+}
+
+// Invoked only as a subprocess, with fake ticket data and no API access.
+func TestTicketPickerProcess(t *testing.T) {
+	args := os.Args
+	if len(args) < 2 || args[len(args)-2] != "--" {
+		return
+	}
+	switch args[len(args)-1] {
+	case "transport":
+		executable, err := os.Executable()
+		if err != nil {
+			t.Fatal(err)
+		}
+		result, err := runTicketCommand("", config.TicketCommand{
+			Command: []string{executable, "-test.run=^TestTicketPickerProcess$", "--", "picker"},
+		}, "")
+		output := map[string]any{"branch": result.BranchName, "metadata": result.Metadata}
+		if err != nil {
+			output["error"] = err.Error()
+		}
+		if err := json.NewEncoder(os.Stdout).Encode(output); err != nil {
+			t.Fatal(err)
+		}
+		os.Exit(0) // Keep the test runner's PASS line out of machine-readable stdout.
+	case "picker":
+		if !term.IsTerminal(os.Stdin.Fd()) || !term.IsTerminal(os.Stderr.Fd()) {
+			fmt.Fprintln(os.Stderr, "picker stdin/stderr must be terminals")
+			os.Exit(2)
+		}
+		result, err := tea.NewProgram(ticketPickerTestModel{}, tea.WithInput(os.Stdin), tea.WithOutput(os.Stderr)).Run()
+		if err != nil {
+			fmt.Fprintln(os.Stderr, err)
+			os.Exit(2)
+		}
+		model := result.(ticketPickerTestModel)
+		if model.selected && model.width == 100 && model.height == 30 {
+			fmt.Println(`{"branchName":"feature/selected","metadata":{"identifier":"TEST-123"}}`)
+			os.Exit(0)
+		}
+		if model.cancelled {
+			os.Exit(23)
+		}
+		fmt.Fprintln(os.Stderr, "picker timed out or received incorrect dimensions")
+		os.Exit(2)
+	}
+}
+
+type ticketPickerTestTimeout struct{}
+
+type ticketPickerTestModel struct {
+	width, height int
+	selected      bool
+	cancelled     bool
+}
+
+func (m ticketPickerTestModel) Init() tea.Cmd {
+	return tea.Tick(5*time.Second, func(time.Time) tea.Msg { return ticketPickerTestTimeout{} })
+}
+
+func (m ticketPickerTestModel) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
+	switch msg := msg.(type) {
+	case tea.WindowSizeMsg:
+		m.width, m.height = msg.Width, msg.Height
+	case tea.KeyPressMsg:
+		switch msg.String() {
+		case "enter":
+			m.selected = true
+			return m, tea.Quit
+		case "esc":
+			m.cancelled = true
+			return m, tea.Quit
+		}
+	case ticketPickerTestTimeout:
+		return m, tea.Quit
+	}
+	return m, nil
+}
+
+func (m ticketPickerTestModel) View() tea.View {
+	view := tea.NewView(fmt.Sprintf("PICKER_READY %dx%d\nEnter selects; Escape cancels", m.width, m.height))
+	view.AltScreen = true
+	return view
+}