3 files changed, 61 insertions, 2 deletions
diff --git a/go/game/playerControl_test.go b/go/game/playerControl_test.go
index 34f20c59..0182e30b 100644
--- a/go/game/playerControl_test.go
+++ b/go/game/playerControl_test.go
@@ -4,6 +4,31 @@ import (
 	"testing"
 )
 
+type MockPlayerControl struct {
+	p                 *Player
+	sentNotifications []PlayerNotification
+}
+
+func newMockPlayerControl(p *Player) PlayerControl {
+	return &MockPlayerControl{p: p}
+}
+
+func (ctrl *MockPlayerControl) Close()          {}
+func (ctrl *MockPlayerControl) Player() *Player { return ctrl.p }
+func (ctrl *MockPlayerControl) RecvNotification() (n PlayerNotification, err error) {
+	return
+}
+
+func (ctrl *MockPlayerControl) SendNotification(n PlayerNotification) error {
+	ctrl.sentNotifications = append(ctrl.sentNotifications, n)
+	return nil
+}
+
+func (ctrl *MockPlayerControl) RecvAction() (Action, error) {
+	return nil, nil
+}
+func (ctrl *MockPlayerControl) SendAction(Action) error { return nil }
+
 const PRORITY_STRING = "!priority{}"
 
 func TestMarshalPriority(t *testing.T) {
diff --git a/go/game/state.go b/go/game/state.go
index f6bcbc8e..b72da192 100644
--- a/go/game/state.go
+++ b/go/game/state.go
@@ -458,6 +458,14 @@ func (s *LocalState) pushAction(a Action) {
 	s.stack.push(a)
 }
 
+type ErrDeclareSlowAction struct {
+	reason string
+}
+
+func (err ErrDeclareSlowAction) Error() string {
+	return err.reason
+}
+
 func (s *LocalState) declareAction(a Action) {
 	var err error
 
@@ -471,8 +479,12 @@ func (s *LocalState) declareAction(a Action) {
 			}
 		case *FreeAction:
 		default:
-			if a.Speed() == ActionSpeeds.Slow && !s.stack.IsEmpty() {
-				err = errors.New("slow action can not be declared while other actions are on the stack")
+			if a.Speed() == ActionSpeeds.Slow {
+				if !s.stack.IsEmpty() {
+					err = ErrDeclareSlowAction{"stack not empty"}
+				} else if s.activePlayerId != a.Controller().Id || s.activePhase != Phases.ActionPhase {
+					err = ErrDeclareSlowAction{"not action phase"}
+				}
 			}
 		}
 	}
diff --git a/go/game/state_test.go b/go/game/state_test.go
new file mode 100644
index 00000000..ad7fdca7
--- /dev/null
+++ b/go/game/state_test.go
@@ -0,0 +1,22 @@
+package game
+
+import (
+	"testing"
+)
+
+func TestDeclareActions(t *testing.T) {
+	s := NewLocalState()
+	s.SetMap(newEmpty2x2Map())
+	p := s.AddNewPlayer("p", NewDeck())
+	p.Ctrl = newMockPlayerControl(p)
+	o := s.AddNewPlayer("o", NewDeck())
+	o.Ctrl = newMockPlayerControl(o)
+	a := s.addNewUnit(NewCard("base/archer"), Position{0, 0}, p)
+	k := s.addNewUnit(NewCard("base/knight"), Position{1, 1}, o)
+	sa := NewAttackAction(a)
+	sa.Target().AddSelection(k)
+	s.declareAction(sa)
+	if !s.stack.IsEmpty() {
+		t.Fatal("declared slow action during upkeep")
+	}
+}