Test that correct pages are displayed for navRailIndexStateProvider value

pubspec.lock

@@ -729,6 +729,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "3.0.0"
+  mockito:
+    dependency: "direct main"
+    description:
+      name: mockito
+      sha256: "6841eed20a7befac0ce07df8116c8b8233ed1f4486a7647c7fc5a02ae6163917"
+      url: "https://pub.dev"
+    source: hosted
+    version: "5.4.4"
   mpv_dart:
     dependency: transitive
     description:

pubspec.yaml

@@ -1,11 +1,11 @@
 name: apidash
 description: API Dash is a beautiful open-source cross-platform API Client built using Flutter which can help you easily create & customize your API requests, visually inspect responses and generate Dart code on the go.
-publish_to: "none"
+publish_to: 'none'
 version: 0.3.0+3
 
 environment:
-  sdk: ">=3.0.0 <4.0.0"
-  flutter: ">=3.7.2"
+  sdk: '>=3.0.0 <4.0.0'
+  flutter: '>=3.7.2'
 
 dependencies:
   flutter:
@@ -55,6 +55,7 @@ dependencies:
   dart_style: ^2.3.4
   json_text_field: ^1.1.0
   csv: ^5.1.1
+  mockito: ^5.4.4
 
 dev_dependencies:
   flutter_test:

test/providers/ui_providers_test.dart

@@ -0,0 +1,93 @@
+import 'dart:io';
+
+import 'package:apidash/providers/providers.dart';
+import 'package:apidash/screens/dashboard.dart';
+import 'package:apidash/screens/home_page/home_page.dart';
+import 'package:apidash/screens/intro_page.dart';
+import 'package:apidash/screens/settings_page.dart';
+import 'package:apidash/services/hive_services.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:mockito/mockito.dart';
+
+class MockPathProviderPlatform extends Mock implements MethodChannel {}
+
+void main() {
+  TestWidgetsFlutterBinding.ensureInitialized();
+
+  setUp(() async {
+    const MethodChannel channel =
+        MethodChannel('plugins.flutter.io/path_provider');
+    final MockPathProviderPlatform mock = MockPathProviderPlatform();
+    TestDefaultBinaryMessengerBinding.instance.defaultBinaryMessenger
+        .setMockMethodCallHandler(channel, (MethodCall methodCall) async {
+      if (methodCall.method == 'getApplicationDocumentsDirectory') {
+        // Create a mock app doc directory for testing
+        Directory tempDir =
+            await Directory.systemTemp.createTemp('mock_app_doc_dir');
+        return tempDir.path; // Return the path to the mock directory
+      }
+      return null;
+    });
+    await openBoxes();
+  });
+
+  group('Testing navRailIndexStateProvider', () {
+    testWidgets('Dashboard should display correct initial page',
+        (tester) async {
+      await tester.pumpWidget(
+        const ProviderScope(
+          child: MaterialApp(
+            home: Dashboard(),
+          ),
+        ),
+      );
+
+      // Verify that the HomePage is displayed initially
+      expect(find.byType(HomePage), findsOneWidget);
+      expect(find.byType(IntroPage), findsNothing);
+      expect(find.byType(SettingsPage), findsNothing);
+    });
+
+    testWidgets(
+        "Dashboard should display IntroPage when navRailIndexStateProvider is 1",
+        (WidgetTester tester) async {
+      await tester.pumpWidget(
+        ProviderScope(
+          overrides: [
+            navRailIndexStateProvider.overrideWith((ref) => 1),
+          ],
+          child: const MaterialApp(
+            home: Dashboard(),
+          ),
+        ),
+      );
+
+      // Verify that the IntroPage is displayed
+      expect(find.byType(IntroPage), findsOneWidget);
+      expect(find.byType(HomePage), findsNothing);
+      expect(find.byType(SettingsPage), findsNothing);
+    });
+    testWidgets(
+        "Dashboard should display SettingsPage when navRailIndexStateProvider is 2",
+        (WidgetTester tester) async {
+      await tester.pumpWidget(
+        ProviderScope(
+          overrides: [
+            navRailIndexStateProvider.overrideWith((ref) => 2),
+          ],
+          child: const MaterialApp(
+            home: Dashboard(),
+          ),
+        ),
+      );
+
+      // Verify that the SettingsPage is displayed
+      expect(find.byType(SettingsPage), findsOneWidget);
+      expect(find.byType(IntroPage), findsNothing);
+      expect(find.byType(HomePage), findsNothing);
+    });
+  });
+}