feat(flutter): 统一文字下拉刷新

test/core/app_pull_to_refresh_test.dart

@@ -0,0 +1,68 @@
+// Author: fruit.com.cn
+
+import 'dart:async';
+
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:fruitshorts/core/widgets/app_pull_to_refresh.dart';
+import 'package:fruitshorts/l10n/app_localizations.dart';
+
+void main() {
+  testWidgets(
+    'should_show_pull_release_and_refreshing_states_and_refresh_once',
+    (tester) async {
+      final refresh = Completer<void>();
+      var calls = 0;
+      await tester.pumpWidget(
+        MaterialApp(
+          locale: const Locale('en'),
+          localizationsDelegates: AppLocalizations.localizationsDelegates,
+          supportedLocales: AppLocalizations.supportedLocales,
+          home: Scaffold(
+            body: AppPullToRefresh(
+              onRefresh: () {
+                calls++;
+                return refresh.future;
+              },
+              child: ListView(
+                key: const Key('pull-refresh-list'),
+                physics: const AlwaysScrollableScrollPhysics(),
+                children: const [SizedBox(height: 1200)],
+              ),
+            ),
+          ),
+        ),
+      );
+
+      final gesture = await tester.startGesture(
+        tester.getCenter(find.byKey(const Key('pull-refresh-list'))),
+      );
+      await gesture.moveBy(const Offset(0, 30));
+      await tester.pump();
+      expect(find.text('Pull to refresh'), findsOneWidget);
+
+      await gesture.moveBy(const Offset(0, 40));
+      await tester.pump();
+      expect(find.text('Release to refresh'), findsOneWidget);
+
+      await gesture.up();
+      await tester.pump();
+      expect(find.text('Refreshing…'), findsOneWidget);
+      expect(calls, 1);
+
+      final duplicate = await tester.startGesture(
+        tester.getCenter(find.byKey(const Key('pull-refresh-list'))),
+      );
+      await duplicate.moveBy(const Offset(0, 70));
+      await duplicate.up();
+      await tester.pump();
+      expect(calls, 1);
+
+      refresh.complete();
+      await tester.pump();
+      await tester.pump(const Duration(milliseconds: 200));
+      expect(find.text('Refreshing…'), findsNothing);
+      expect(find.text('Pull to refresh'), findsNothing);
+    },
+  );
+}