core: mock wayland context for tests & add i18n guidance to CONTRIBUTING

core/internal/server/wayland/manager.go

@@ -19,7 +19,7 @@ import (
 
 const animKelvinStep = 25
 
-func NewManager(display *wlclient.Display, config Config) (*Manager, error) {
+func NewManager(display wlclient.WaylandDisplay, config Config) (*Manager, error) {
 	if err := config.Validate(); err != nil {
 		return nil, err
 	}

core/internal/server/wayland/manager_test.go

@@ -1,11 +1,14 @@
 package wayland
 
 import (
+	"errors"
 	"sync"
 	"testing"
 	"time"
 
 	"github.com/stretchr/testify/assert"
+
+	mocks_wlclient "github.com/AvengeMedia/DankMaterialShell/core/internal/mocks/wlclient"
 )
 
 func TestManager_ActorSerializesOutputStateAccess(t *testing.T) {
@@ -384,3 +387,28 @@ func TestNotifySubscribers_NonBlocking(t *testing.T) {
 
 	assert.Len(t, m.dirty, 1)
 }
+
+func TestNewManager_GetRegistryError(t *testing.T) {
+	mockDisplay := mocks_wlclient.NewMockWaylandDisplay(t)
+
+	mockDisplay.EXPECT().Context().Return(nil)
+	mockDisplay.EXPECT().GetRegistry().Return(nil, errors.New("failed to get registry"))
+
+	config := DefaultConfig()
+	_, err := NewManager(mockDisplay, config)
+	assert.Error(t, err)
+	assert.Contains(t, err.Error(), "get registry")
+}
+
+func TestNewManager_InvalidConfig(t *testing.T) {
+	mockDisplay := mocks_wlclient.NewMockWaylandDisplay(t)
+
+	config := Config{
+		LowTemp:  500,
+		HighTemp: 6500,
+		Gamma:    1.0,
+	}
+
+	_, err := NewManager(mockDisplay, config)
+	assert.Error(t, err)
+}

core/internal/server/wayland/types.go

@@ -65,7 +65,7 @@ type Manager struct {
 	state       *State
 	stateMutex  sync.RWMutex
 
-	display             *wlclient.Display
+	display             wlclient.WaylandDisplay
 	ctx                 *wlclient.Context
 	registry            *wlclient.Registry
 	gammaControl        any