[test] Flutter unit testing

.github/workflows/linux.yml

@@ -235,7 +235,7 @@ jobs:
            ulimit -c unlimited &&        \
            env CTEST_OUTPUT_ON_FAILURE=1 \
            LD_LIBRARY_PATH=/root/stage/usr/lib/x86_64-linux-gnu/:/root/stage/lib/:/root/parts/multipass/build/lib/ \
-           /root/parts/multipass/build/bin/multipass_tests"
+           ctest -V"
 
     - name: Measure coverage
       id: measure-coverage

.github/workflows/macos.yml

@@ -254,7 +254,7 @@ jobs:
         trap 'echo "MULTIPASS_TESTS_EXIT_CODE=$?" >> $GITHUB_ENV' EXIT
         # Set soft limit for the core file size (512MiB)
         ulimit -c 1048576
-        bin/multipass_tests
+        ctest -V
 
     - name: Upload test coredump
       uses: actions/upload-artifact@v7

.github/workflows/windows.yml

@@ -176,7 +176,7 @@ jobs:
     - name: Test
       working-directory: ${{ env.BUILD_DIR }}
       run: |
-        bin/multipass_tests
+        ctest -V
 
     - name: Package
       id: cmake-package

CMakeLists.txt

@@ -351,7 +351,22 @@ if(cmake_build_type_lower MATCHES "coverage")
         ${CMAKE_BINARY_DIR}'/*'
         --output-file coverage.cleaned
       COMMAND ${CMAKE_COMMAND} -E remove coverage.info
-      COMMAND ${GENHTML} -o coverage coverage.cleaned
+
+      # Merge Flutter test coverage with C++ coverage
+      COMMAND ${CMAKE_COMMAND} -E chdir ${CMAKE_SOURCE_DIR}/src/client/gui
+              ${FLUTTER_EXECUTABLE} test --coverage
+      COMMAND ${LCOV}
+        --remove ${CMAKE_SOURCE_DIR}/src/client/gui/coverage/lcov.info
+        --ignore-errors unused
+        '*/lib/generated/*'
+        '*/lib/l10n/*'
+        --output-file ${CMAKE_SOURCE_DIR}/src/client/gui/coverage/lcov.info
+      COMMAND ${LCOV}
+        --add-tracefile coverage.cleaned
+        --add-tracefile ${CMAKE_SOURCE_DIR}/src/client/gui/coverage/lcov.info
+        --output-file coverage.cleaned
+
+      COMMAND ${GENHTML} --source-directory ${CMAKE_SOURCE_DIR}/src/client/gui -o coverage coverage.cleaned
     )
   endif()
 endif()
@@ -369,6 +384,14 @@ add_subdirectory(src)
 if(MULTIPASS_ENABLE_TESTS)
   enable_testing()
   add_subdirectory(tests/unit)
+
+  if(MULTIPASS_ENABLE_FLUTTER_GUI)
+    add_test(
+      NAME multipass_gui_tests
+      COMMAND ${FLUTTER_EXECUTABLE} test
+      WORKING_DIRECTORY ${CMAKE_SOURCE_DIR}/src/client/gui
+    )
+  endif()
 endif()
 
 include(packaging/cpack.cmake OPTIONAL)

src/client/gui/test/catalogue/catalogue_screen_test.dart

@@ -0,0 +1,91 @@
+import 'dart:async';
+
+import 'package:flutter/material.dart' hide ImageInfo;
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:multipass_gui/catalogue/catalogue.dart';
+import 'package:multipass_gui/grpc_client.dart';
+import 'package:multipass_gui/l10n/app_localizations.dart';
+
+import '../helpers.dart';
+
+Widget _scope(Widget child) {
+  return withFakeSvgAssetBundle(
+    MaterialApp(
+      localizationsDelegates: AppLocalizations.localizationsDelegates,
+      supportedLocales: AppLocalizations.supportedLocales,
+      home: child,
+    ),
+  );
+}
+
+void main() {
+  group('CatalogueScreen', () {
+    testWidgets('shows a loading indicator while images are fetching',
+        (tester) async {
+      await tester.pumpWidget(
+        ProviderScope(
+          overrides: [
+            imagesProvider.overrideWith(
+              (ref) => Completer<List<ImageInfo>>().future,
+            ),
+          ],
+          child: _scope(const CatalogueScreen()),
+        ),
+      );
+      // One pump to trigger the first build before the future resolves.
+      await tester.pump();
+
+      expect(find.byType(CircularProgressIndicator), findsOneWidget);
+    });
+
+    testWidgets('shows an error message when images fail to load',
+        (tester) async {
+      await tester.pumpWidget(
+        ProviderScope(
+          overrides: [
+            imagesProvider.overrideWith((ref) async {
+              throw Exception('Connection failed');
+            }),
+          ],
+          child: _scope(const CatalogueScreen()),
+        ),
+      );
+      await tester.pumpAndSettle();
+
+      expect(find.textContaining('Connection failed'), findsOneWidget);
+    });
+
+    testWidgets('shows a refresh button when images fail to load',
+        (tester) async {
+      await tester.pumpWidget(
+        ProviderScope(
+          overrides: [
+            imagesProvider.overrideWith((ref) async {
+              throw Exception('Load error');
+            }),
+          ],
+          child: _scope(const CatalogueScreen()),
+        ),
+      );
+      await tester.pumpAndSettle();
+
+      expect(find.text('Refresh'), findsOneWidget);
+    });
+
+    testWidgets('shows the welcome title when images are successfully loaded',
+        (tester) async {
+      await tester.pumpWidget(
+        ProviderScope(
+          overrides: [
+            imagesProvider.overrideWith((ref) async => []),
+          ],
+          child: _scope(const CatalogueScreen()),
+        ),
+      );
+      await tester.pumpAndSettle();
+
+      expect(find.text('Welcome to Multipass'), findsOneWidget);
+    });
+  });
+}