[shared_preferences] Allow reading int as long in SharedPreferences #165781 (#9032)

Resolves issue [#165781](flutter/flutter#165781) by falling back to reading preference as an int then upcasted to a Long.

## Pre-Review Checklist

[^1]: Regular contributors who have demonstrated familiarity with the repository guidelines only need to comment if the PR is not auto-exempted by repo tooling.

Author: ash2moon

packages/shared_preferences/shared_preferences_android/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 2.4.9
+
+* Enables callers to use `getInt` to read preference of type `int` that was written to shared preferences by native code without passing though plugin code.
+
 ## 2.4.8
 
 * Updates compileSdk 34 to flutter.compileSdkVersion.

packages/shared_preferences/shared_preferences_android/android/src/main/kotlin/io/flutter/plugins/sharedpreferences/SharedPreferencesPlugin.kt

@@ -23,6 +23,7 @@ import io.flutter.plugin.common.BinaryMessenger
 import java.io.ByteArrayInputStream
 import java.io.ByteArrayOutputStream
 import java.io.ObjectOutputStream
+import java.lang.ClassCastException
 import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.firstOrNull
 import kotlinx.coroutines.flow.map
@@ -379,7 +380,12 @@ class SharedPreferencesBackend(
   override fun getInt(key: String, options: SharedPreferencesPigeonOptions): Long? {
     val preferences = createSharedPreferences(options)
     return if (preferences.contains(key)) {
-      preferences.getLong(key, 0)
+      try {
+        preferences.getLong(key, 0)
+      } catch (e: ClassCastException) {
+        // Retry with getInt in case the preference was written by native code directly.
+        preferences.getInt(key, 0).toLong()
+      }
     } else {
       null
     }

packages/shared_preferences/shared_preferences_android/example/android/app/src/main/java/dev/flutter/plugins/shared_preferences_example/MainActivity.java

@@ -17,9 +17,10 @@ public void configureFlutterEngine(@NonNull FlutterEngine flutterEngine) {
     SharedPreferences preferences =
         PreferenceManager.getDefaultSharedPreferences(getApplicationContext());
 
-    // This call adds a preference for later testing in the Dart integration tests.
+    // These calls add preferences for later testing in the Dart integration tests.
     preferences
         .edit()
+        .putInt("thisIntIsWrittenInTheExampleAppJavaCode", 5)
         .putString("thisStringIsWrittenInTheExampleAppJavaCode", "testString")
         .commit();
   }

packages/shared_preferences/shared_preferences_android/example/integration_test/shared_preferences_test.dart

@@ -914,4 +914,16 @@ void main() {
             'thisStringIsWrittenInTheExampleAppJavaCode', options),
         'testString');
   });
+
+  testWidgets('Shared Preferences can read ints by conversion to long',
+      (WidgetTester _) async {
+    final SharedPreferencesAsyncAndroidOptions options =
+        getOptions(useDataStore: false);
+    final SharedPreferencesAsyncPlatform preferences = getPreferences();
+
+    expect(
+        await preferences.getInt(
+            'thisIntIsWrittenInTheExampleAppJavaCode', options),
+        5);
+  });
 }

packages/shared_preferences/shared_preferences_android/pubspec.yaml

@@ -2,7 +2,7 @@ name: shared_preferences_android
 description: Android implementation of the shared_preferences plugin
 repository: https://github.com/flutter/packages/tree/main/packages/shared_preferences/shared_preferences_android
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+shared_preferences%22
-version: 2.4.8
+version: 2.4.9
 
 environment:
   sdk: ^3.6.0