fix: Token was not being resolved correctly

packages/mix/lib/src/core/factory/mix_data.dart

@@ -108,7 +108,7 @@ class MixData with Diagnosticable {
   // /// Merges this [MixData] with another, prioritizing this instance's properties.
   MixData merge(MixData other) {
     return MixData._(
-      resolver: _tokenResolver,
+      resolver: other._tokenResolver,
       attributes: _attributes.merge(other._attributes),
       animation: other.animation ?? animation,
     );

packages/mix/test/src/core/factory/mix_data_test.dart

@@ -0,0 +1,89 @@
+import 'package:flutter/widgets.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:mix/mix.dart';
+
+import '../../../helpers/testing_utils.dart';
+
+// Define theme color tokens
+const _surface = ColorToken('surface');
+const _onSurface = ColorToken('onSurface');
+
+// Light theme
+final _lightTheme = MixThemeData(
+  colors: {
+    _surface: const Color(0xFF000000),
+    _onSurface: const Color(0xFFFFFFFF),
+  },
+);
+
+// Dark theme
+final _darkTheme = MixThemeData(
+  colors: {
+    _surface: const Color(0xFFFFFFFF),
+    _onSurface: const Color(0xFF000000),
+  },
+);
+
+// Widget wrapper that allows toggling between themes
+class _ThemeToggleWrapper extends StatefulWidget {
+  const _ThemeToggleWrapper({required this.child});
+
+  final Widget child;
+
+  @override
+  State<_ThemeToggleWrapper> createState() => _ThemeToggleWrapperState();
+}
+
+class _ThemeToggleWrapperState extends State<_ThemeToggleWrapper> {
+  bool isDark = false;
+
+  void toggleTheme() {
+    setState(() {
+      isDark = !isDark;
+    });
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return MixTheme(
+      data: isDark ? _darkTheme : _lightTheme,
+      child: widget.child,
+    );
+  }
+}
+
+// Sample widget that uses theme colors
+class _ThemedBox extends StatelessWidget {
+  const _ThemedBox();
+
+  @override
+  Widget build(BuildContext context) {
+    return Box(
+      style: Style($box.color.ref(_surface)),
+      child: StyledText('test', style: Style($text.color.ref(_onSurface))),
+    );
+  }
+}
+
+void main() {
+  testWidgets('should update colors when theme changes', (tester) async {
+    await tester.pumpMaterialApp(
+      const _ThemeToggleWrapper(child: _ThemedBox()),
+    );
+
+    final themeToggle = tester.state<_ThemeToggleWrapperState>(
+      find.byType(_ThemeToggleWrapper),
+    );
+
+    Text text = tester.widget<Text>(find.byType(Text));
+    expect(themeToggle.isDark, isFalse);
+    expect(text.style?.color, const Color(0xFFFFFFFF));
+
+    themeToggle.toggleTheme();
+    await tester.pump();
+
+    text = tester.widget<Text>(find.byType(Text));
+    expect(themeToggle.isDark, isTrue);
+    expect(text.style?.color, const Color(0xFF000000));
+  });
+}