add traction import export

test/pages/traction_page_test.dart

@@ -0,0 +1,114 @@
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:go_router/go_router.dart';
+import 'package:shared_preferences/shared_preferences.dart';
+
+import 'package:mileograph_flutter/components/pages/traction.dart';
+
+import '../helpers/fake_services.dart';
+import '../helpers/test_app.dart';
+import '../helpers/test_data.dart';
+
+void main() {
+  TestWidgetsFlutterBinding.ensureInitialized();
+
+  setUpAll(() {
+    SharedPreferences.setMockInitialValues({});
+  });
+
+  testWidgets('Traction page shows list data', (tester) async {
+    final data = FakeDataService()
+      ..tractionValue = TestData.traction
+      ..locoClassesValue = ['67', '68']
+      ..eventFieldsValue = TestData.eventFields;
+    final auth = FakeAuthService(api: FakeApiService(), isElevatedValue: true);
+    final router = GoRouter(
+      routes: [
+        GoRoute(
+          path: '/',
+          builder: (context, state) => const TractionPage(),
+        ),
+      ],
+    );
+
+    await tester.pumpWidget(
+      buildTestRouterApp(
+        router: router,
+        dataService: data,
+        authService: auth,
+      ),
+    );
+    await tester.pumpAndSettle();
+
+    expect(find.text('Traction'), findsOneWidget);
+    expect(find.text('67'), findsWidgets);
+    expect(find.text('001'), findsWidgets);
+  });
+
+  testWidgets('Traction page shows export when class filter set', (tester) async {
+    final data = FakeDataService()
+      ..tractionValue = TestData.traction
+      ..locoClassesValue = ['67', '68']
+      ..eventFieldsValue = TestData.eventFields;
+    final auth = FakeAuthService(api: FakeApiService(), isElevatedValue: true);
+    final router = GoRouter(
+      routes: [
+        GoRoute(
+          path: '/',
+          builder: (context, state) => const TractionPage(),
+        ),
+      ],
+    );
+
+    await tester.pumpWidget(
+      buildTestRouterApp(
+        router: router,
+        dataService: data,
+        authService: auth,
+      ),
+    );
+    await tester.pumpAndSettle();
+
+    expect(find.textContaining('Export'), findsNothing);
+
+    final classField = find.byWidgetPredicate(
+      (widget) =>
+          widget is TextField && widget.decoration?.labelText == 'Class',
+    );
+    await tester.enterText(classField, '67');
+    await tester.pump();
+
+    expect(find.text('Export 67'), findsOneWidget);
+  });
+
+  testWidgets('Traction page shows admin import option', (tester) async {
+    final data = FakeDataService()
+      ..tractionValue = TestData.traction
+      ..locoClassesValue = ['67', '68']
+      ..eventFieldsValue = TestData.eventFields
+      ..pendingLocoCountValue = 2;
+    final auth = FakeAuthService(api: FakeApiService(), isElevatedValue: true);
+    final router = GoRouter(
+      routes: [
+        GoRoute(
+          path: '/',
+          builder: (context, state) => const TractionPage(),
+        ),
+      ],
+    );
+
+    await tester.pumpWidget(
+      buildTestRouterApp(
+        router: router,
+        dataService: data,
+        authService: auth,
+      ),
+    );
+    await tester.pumpAndSettle();
+
+    await tester.tap(find.byType(PopupMenuButton));
+    await tester.pumpAndSettle();
+
+    expect(find.text('Import traction'), findsOneWidget);
+  });
+}