fix(tmux): Fix tmux.Server.ListSessions when the server isn't running. (

#1)

api/exec/exec.go

@@ -75,7 +75,7 @@ func (cmd *Command) Start() error {
 	start := time.Now()
 	logger := slog.Default().With("command", cmd)
 	logger.Debug("Executing external process. (1/2)")
-	err := cmd.Start()
+	err := cmd.cmd.Start()
 	go func() {
 		cmd.Wait()
 		logger.Debug("Executing external process. (2/2)", "elapsed", time.Since(start), "exit_code", cmd.ProcessState.ExitCode())

tmux/server.go

@@ -124,8 +124,12 @@ func (srv *Server) Equal(other *Server) bool {
 // ListSessions lists the sessions that exist in this tmux server.
 // This method will also lookup and cache the given properties.
 func (srv *Server) ListSessions() ([]*Session, error) {
-	stdout, err := srv.command("list-sessions", "-F", string(SessionID)).RunStdout()
+	stdout, stderr, err := srv.command("list-sessions", "-F", string(SessionID)).RunOutput()
 	if err != nil {
+		if strings.Contains(stderr, "no server running") {
+			return nil, nil
+		}
+		fmt.Fprint(os.Stderr, stderr)
 		return nil, err
 	}
 	var res []*Session

tmux/tmux_test.go

@@ -166,11 +166,17 @@ func RunInTTY(t *testing.T, cmd *exec.Command) *os.File {
 
 func TestServer_Sessions(t *testing.T) {
 	srv := NewServerForTesting(t)
+
+	sessions := srv.MustListSessions()
+	if len(sessions) != 0 {
+		t.Errorf("New tmux server has %d sessions, expected 0", len(sessions))
+	}
+
 	a := srv.MustNewSession(NewSessionName("a"))
 	b := srv.MustNewSession(NewSessionName("b"))
 	c := srv.MustNewSession(NewSessionName("c"))
 
-	sessions := srv.MustListSessions()
+	sessions = srv.MustListSessions()
 	if diff := cmp.Diff([]TestSession{a, b, c}, sessions, tmuxCmpOpt); diff != "" {
 		t.Errorf("srv.ListSessions() diff (-want +got)\n%s", diff)
 	}