From fb3abba49821f1a0f786aafd705b91ced421ff5c Mon Sep 17 00:00:00 2001
From: Taha Tesser <tessertaha@gmail.com>
Date: Sat, 7 Oct 2023 20:00:42 +0300
Subject: [PATCH] Throw a helpful error message when returning an empty list in
 `pageListBuilder`

---
 lib/src/wolt_modal_sheet.dart   | 1 +
 test/wolt_modal_sheet_test.dart | 4 +++-
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/lib/src/wolt_modal_sheet.dart b/lib/src/wolt_modal_sheet.dart
index b0ab1817..e8e5af72 100644
--- a/lib/src/wolt_modal_sheet.dart
+++ b/lib/src/wolt_modal_sheet.dart
@@ -215,6 +215,7 @@ class _WoltModalSheetState extends State<WoltModalSheet> {
         valueListenable: pagesListBuilderNotifier,
         builder: (context, pagesBuilder, _) {
           final pages = pagesBuilder(context);
+          assert(pages.isNotEmpty, 'pageListBuilder must return a non-empty list.');
           return ValueListenableBuilder<int>(
             valueListenable: pageIndexNotifier,
             builder: (_, int pageIndex, __) {
diff --git a/test/wolt_modal_sheet_test.dart b/test/wolt_modal_sheet_test.dart
index 5291f675..b2d89ad6 100644
--- a/test/wolt_modal_sheet_test.dart
+++ b/test/wolt_modal_sheet_test.dart
@@ -59,7 +59,9 @@ void main() {
       await tester.tap(find.text('Open sheet'));
       await tester.pumpAndSettle();
 
-      expect(tester.takeException(), isNotNull);
+      final AssertionError exception = tester.takeException() as AssertionError;
+      expect(exception, isAssertionError);
+      expect(exception.message, 'pageListBuilder must return a non-empty list.');
     });
   });