refactor(i18n): add service snapshot stringers

Co-Authored-By: Virgil <virgil@lethean.io>

core_service.go

@@ -347,6 +347,11 @@ func (s *CoreService) CurrentState() ServiceState {
 	return s.State()
 }
 
+// String returns a concise snapshot of the wrapped service state.
+func (s *CoreService) String() string {
+	return s.State().String()
+}
+
 // AddHandler appends handlers to the wrapped service's chain.
 func (s *CoreService) AddHandler(handlers ...KeyHandler) {
 	if svc := s.wrapped(); svc != nil {

core_service_test.go

@@ -35,6 +35,7 @@ func TestCoreServiceNilSafe(t *testing.T) {
 		assert.Equal(t, core.Result{Value: "hello", OK: false}, svc.Translate("hello"))
 		assert.Equal(t, defaultServiceStateSnapshot(), svc.State())
 		assert.Equal(t, defaultServiceStateSnapshot(), svc.CurrentState())
+		assert.Equal(t, defaultServiceStateSnapshot().String(), svc.String())
 	})
 	assert.Nil(t, defaultService.Load())
 

service_test.go

@@ -280,6 +280,9 @@ func TestServiceNilReceiverIsSafe(t *testing.T) {
 	if got, want := svc.State(), defaultServiceStateSnapshot(); got.Language != want.Language || got.Mode != want.Mode || got.Fallback != want.Fallback || got.Formality != want.Formality || got.Location != want.Location || got.Direction != want.Direction || got.IsRTL != want.IsRTL || got.Debug != want.Debug || len(got.AvailableLanguages) != len(want.AvailableLanguages) || len(got.Handlers) != len(want.Handlers) {
 		t.Fatalf("nil Service.State() = %+v, want %+v", got, want)
 	}
+	if got, want := svc.String(), defaultServiceStateSnapshot().String(); got != want {
+		t.Fatalf("nil Service.String() = %q, want %q", got, want)
+	}
 	if got, want := svc.T("prompt.yes"), "prompt.yes"; got != want {
 		t.Fatalf("nil Service.T(prompt.yes) = %q, want %q", got, want)
 	}

state.go

@@ -160,6 +160,11 @@ func (s *Service) State() ServiceState {
 	)
 }
 
+// String returns a concise snapshot of the service state.
+func (s *Service) String() string {
+	return s.State().String()
+}
+
 // CurrentState is a more explicit alias for State.
 func (s *Service) CurrentState() ServiceState {
 	return s.State()