Invalidate V8 DateTime cache on timezone changes

test-app/app/src/main/java/com/tns/RuntimeHelper.java

@@ -3,16 +3,22 @@
 import java.io.File;
 
 import android.app.Application;
+import android.content.BroadcastReceiver;
 import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.content.SharedPreferences;
 import android.content.pm.PackageManager.NameNotFoundException;
 import android.os.Build;
+import android.preference.PreferenceManager;
 import android.util.Log;
 
 import java.io.IOException;
 import java.lang.reflect.Constructor;
 import java.lang.reflect.Field;
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
+import java.util.TimeZone;
 
 public final class RuntimeHelper {
     private RuntimeHelper() {
@@ -233,12 +239,54 @@ public static Runtime initRuntime(Application app) {
                     }
                     e.printStackTrace();
                 }
+
+                if (appConfig.handleTimeZoneChanges()) {
+                    // If the user sets this flag, we will register a broadcast receiver
+                    // that will listen for the TIMEZONE_CHANGED event and update V8's cache
+                    // so that subsequent calls to "new Date()" return the new timezone
+                    registerTimezoneChangedListener(app, runtime);
+                }
             }
             return runtime;
         } finally {
             frame.close();
         }
     }
 
+    private static void registerTimezoneChangedListener(Context context, final Runtime runtime) {
+        IntentFilter timezoneFilter = new IntentFilter(Intent.ACTION_TIMEZONE_CHANGED);
+
+        BroadcastReceiver timezoneReceiver = new BroadcastReceiver() {
+            @Override
+            public void onReceive(Context context, Intent intent) {
+                String action = intent.getAction();
+                if (action == null || !action.equals(Intent.ACTION_TIMEZONE_CHANGED)) {
+                    return;
+                }
+
+                SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context);
+
+                String oldTimezone = prefs.getString(PREF_TIMEZONE, null);
+                String newTimezone = TimeZone.getDefault().getID();
+                if (newTimezone == null) {
+                    newTimezone = "";
+                }
+
+                if (oldTimezone == null) {
+                    oldTimezone = "";
+                }
+
+                if (!oldTimezone.equals(newTimezone)) {
+                    prefs.edit().putString(PREF_TIMEZONE, newTimezone).commit();
+                    // Notify V8 for the timezone change
+                    runtime.ResetDateTimeConfigurationCache();
+                }
+            }
+        };
+
+        context.registerReceiver(timezoneReceiver, timezoneFilter);
+    }
+
     private static final String logTag = "MyApp";
+    private static final String PREF_TIMEZONE = "_android_runtime_pref_timezone_";
 }

test-app/runtime/src/main/cpp/com_tns_Runtime.cpp

@@ -347,4 +347,14 @@ extern "C" JNIEXPORT void Java_com_tns_Runtime_CallWorkerObjectOnErrorHandleMain
     } catch (NativeScriptException& e) {
         e.ReThrowToJava();
     }
+}
+
+extern "C" JNIEXPORT void Java_com_tns_Runtime_ResetDateTimeConfigurationCache(JNIEnv* _env, jobject obj, jint runtimeId) {
+    auto runtime = TryGetRuntime(runtimeId);
+    if (runtime == nullptr) {
+        return;
+    }
+
+    auto isolate = runtime->GetIsolate();
+    Date::DateTimeConfigurationChangeNotification(isolate);
 }

test-app/runtime/src/main/java/com/tns/AppConfig.java

@@ -16,7 +16,8 @@ protected enum KnownKeys {
         MemoryCheckInterval("memoryCheckInterval", 0),
         FreeMemoryRatio("freeMemoryRatio", 0.0),
         Profiling("profiling", ""),
-        MarkingMode("markingMode", com.tns.MarkingMode.full);
+        MarkingMode("markingMode", com.tns.MarkingMode.full),
+        HandleTimeZoneChanges("handleTimeZoneChanges", false);
 
         private final String name;
         private final Object defaultValue;
@@ -100,6 +101,9 @@ public AppConfig(File appDir) {
                             Log.v("JS", "Failed to parse marking mode. The default " + ((MarkingMode)KnownKeys.MarkingMode.getDefaultValue()).name() + " will be used.");
                         }
                     }
+                    if (androidObject.has(KnownKeys.HandleTimeZoneChanges.getName())) {
+                        values[KnownKeys.HandleTimeZoneChanges.ordinal()] = androidObject.getBoolean(KnownKeys.HandleTimeZoneChanges.getName());
+                    }
                 }
             }
         } catch (Exception e) {
@@ -138,4 +142,8 @@ public String getProfilingMode() {
     public MarkingMode getMarkingMode() {
         return (MarkingMode)values[KnownKeys.MarkingMode.ordinal()];
     }
+
+    public boolean handleTimeZoneChanges() {
+        return (boolean)values[KnownKeys.HandleTimeZoneChanges.ordinal()];
+    }
 }

test-app/runtime/src/main/java/com/tns/Runtime.java

@@ -66,6 +66,8 @@ public class Runtime {
 
     private static native void CallWorkerObjectOnErrorHandleMain(int runtimeId, int workerId, String message, String stackTrace, String filename, int lineno, String threadName) throws NativeScriptException;
 
+    private static native void ResetDateTimeConfigurationCache(int runtimeId);
+
     void passUncaughtExceptionToJs(Throwable ex, String stackTrace) {
         passUncaughtExceptionToJsNative(getRuntimeId(), ex, stackTrace);
     }
@@ -224,6 +226,13 @@ public Handler getHandler() {
         return this.threadScheduler.getHandler();
     }
 
+    public void ResetDateTimeConfigurationCache() {
+        Runtime runtime = getCurrentRuntime();
+        if (runtime != null) {
+            ResetDateTimeConfigurationCache(runtime.getRuntimeId());
+        }
+    }
+
     private static class WorkerThreadHandler extends Handler {
         @Override
         public void handleMessage(Message msg) {