Tentacle support enhancements.

internal/tentacle/remote_test.go

@@ -123,6 +123,54 @@ func remoteCall(t *testing.T, session *Session, method string, params any) (json
 	return result.Value, result.Code
 }
 
+func TestRemoteWorkflowEpochCleanup(t *testing.T) {
+	manager, err := NewManager(DefaultLimits(), nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(func() {
+		ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+		defer cancel()
+		if err := manager.Shutdown(ctx); err != nil {
+			t.Error(err)
+		}
+	})
+	session := startSessionSDK(t, manager, "go", "workflow")
+	first, err := session.AuthorizeRemote("controller", []string{"remote-present"})
+	if err != nil {
+		t.Fatal(err)
+	}
+	second, err := session.AuthorizeRemote("controller", []string{"remote-present"})
+	if err != nil {
+		t.Fatal(err)
+	}
+	session.RevokeRemoteEpoch(first.Epoch)
+	raw, code := remoteCall(t, session, "remote.open", tentaclewire.RemoteOpen{Action: second.Action, Epoch: second.Epoch, Role: second.Role, Grants: second.Grants})
+	var lease tentaclewire.RemoteLease
+	if code != 0 || json.Unmarshal(raw, &lease) != nil {
+		t.Fatal("old workflow revoked its replacement")
+	}
+	delivery, err := session.RemoteContext(lease, "remote-present")
+	if err != nil {
+		t.Fatal(err)
+	}
+	session.RevokeRemoteEpoch(second.Epoch)
+	if delivery.Err() == nil {
+		t.Fatal("workflow close retained its live lease")
+	}
+	// Pending actions also release exclusive ownership on close, before their
+	// timeout and without requiring a remote.open/remote.close pair.
+	pending, err := session.AuthorizeRemote("controller", []string{"remote-present"})
+	if err != nil {
+		t.Fatal(err)
+	}
+	session.RevokeRemoteEpoch(pending.Epoch)
+	other := startSessionSDK(t, manager, "go", "other-workflow")
+	if _, err := other.AuthorizeRemote("controlled", []string{"output-observe"}); err != nil {
+		t.Fatal("closed setup retained exclusive ownership", err)
+	}
+}
+
 func openRemote(t *testing.T, session *Session) tentaclewire.RemoteLease {
 	t.Helper()
 	action, err := session.AuthorizeRemote("controlled", []string{"output-observe"})