Preserve dialog callback dismissal behavior (#8951)

Author: atavism

lib/core/common/app_dialog.dart

@@ -259,6 +259,9 @@ class AppDialog {
       body: content,
       primaryLabel: action ?? 'ok'.i18n,
       onPrimaryPressed: onPressed,
+      // Preserve the original dialog contract: when a callback is supplied,
+      // it is responsible for dismissing or replacing the current route.
+      dismissOnPrimary: onPressed == null,
     );
   }
 }

test/core/common/app_dialog_test.dart

@@ -0,0 +1,84 @@
+import 'package:flutter/material.dart';
+import 'package:flutter_screenutil/flutter_screenutil.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:lantern/core/common/app_dialog.dart';
+import 'package:lantern/core/common/app_theme.dart';
+
+void main() {
+  testWidgets('dialog callback does not pop the route beneath the dialog', (
+    tester,
+  ) async {
+    await tester.pumpWidget(
+      ScreenUtilInit(
+        designSize: const Size(390, 844),
+        child: MaterialApp(theme: AppTheme.appTheme(), home: const _HomePage()),
+      ),
+    );
+    await tester.pumpAndSettle();
+
+    await tester.tap(find.byKey(const Key('home.open_page')));
+    await tester.pumpAndSettle();
+    expect(find.byKey(const Key('dialog_page')), findsOneWidget);
+
+    await tester.tap(find.byKey(const Key('dialog_page.open_dialog')));
+    await tester.pumpAndSettle();
+    expect(find.text('Dialog title'), findsOneWidget);
+
+    await tester.tap(find.text('Close'));
+    await tester.pump();
+    await tester.pump(const Duration(milliseconds: 500));
+    await tester.pumpAndSettle();
+
+    expect(find.text('Dialog title'), findsNothing);
+    expect(find.byKey(const Key('dialog_page')), findsOneWidget);
+    expect(find.byKey(const Key('home')), findsNothing);
+  });
+}
+
+class _HomePage extends StatelessWidget {
+  const _HomePage();
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      key: const Key('home'),
+      body: Center(
+        child: ElevatedButton(
+          key: const Key('home.open_page'),
+          onPressed: () {
+            Navigator.of(context).push<void>(
+              MaterialPageRoute<void>(builder: (_) => const _DialogPage()),
+            );
+          },
+          child: const Text('Open page'),
+        ),
+      ),
+    );
+  }
+}
+
+class _DialogPage extends StatelessWidget {
+  const _DialogPage();
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      key: const Key('dialog_page'),
+      body: Center(
+        child: ElevatedButton(
+          key: const Key('dialog_page.open_dialog'),
+          onPressed: () {
+            AppDialog.dialog(
+              context: context,
+              title: 'Dialog title',
+              content: 'Dialog body',
+              action: 'Close',
+              onPressed: () => Navigator.of(context).pop(),
+            );
+          },
+          child: const Text('Open dialog'),
+        ),
+      ),
+    );
+  }
+}