fix: Notify listeners when keys get removed (remove/clearAll) (#920)

* fix: Notify on key delete

* Update HybridMMKV.cpp

* update test for correctness

Author: mrousavy

example/__tests__/MMKV.harness.ts

@@ -796,15 +796,13 @@ describe('MMKV Listeners & Observers', () => {
       // Wait for the listeners to trigger
       await waitForNextTick();
 
-      const changesBefore = changedKeys.length;
-
       storage.clearAll();
 
-      // Wait for potential listeners to trigger (but they shouldn't for clearAll)
+      // Wait for the listeners to trigger
       await waitForNextTick();
 
-      // clearAll should not trigger individual key change events
-      expect(changedKeys.length).toStrictEqual(changesBefore);
+      // We did 2x set and a clearAll (clears 2x keys)
+      expect(changedKeys.length).toStrictEqual(4);
 
       listener.remove();
     });

packages/react-native-mmkv/cpp/HybridMMKV.cpp

@@ -145,13 +145,23 @@ bool HybridMMKV::contains(const std::string& key) {
   return instance->containsKey(key);
 }
 bool HybridMMKV::remove(const std::string& key) {
-  return instance->removeValueForKey(key);
+  bool wasRemoved = instance->removeValueForKey(key);
+  if (wasRemoved) {
+    // Notify on changed
+    MMKVValueChangedListenerRegistry::notifyOnValueChanged(instance->mmapID(), key);
+  }
+  return wasRemoved;
 }
 std::vector<std::string> HybridMMKV::getAllKeys() {
   return instance->allKeys();
 }
 void HybridMMKV::clearAll() {
+  auto keysBefore = getAllKeys();
   instance->clearAll();
+  for (const auto& key : keysBefore) {
+    // Notify on changed
+    MMKVValueChangedListenerRegistry::notifyOnValueChanged(instance->mmapID(), key);
+  }
 }
 void HybridMMKV::recrypt(const std::optional<std::string>& key) {
   bool successful = false;

packages/react-native-mmkv/src/createMMKV/createMMKV.web.ts

@@ -80,19 +80,29 @@ export function createMMKV(
     return `${keyPrefix}${key}`
   }
 
+  const callListeners = (key: string) => {
+    listeners.forEach((l) => l(key))
+  }
+
   return {
     clearAll: () => {
       const keys = Object.keys(storage())
       for (const key of keys) {
         if (key.startsWith(keyPrefix)) {
           storage().removeItem(key)
+          callListeners(key)
         }
       }
     },
-    remove: (key) => storage().removeItem(prefixedKey(key)) ?? false,
+    remove: (key) => {
+      const wasRemoved = storage().removeItem(prefixedKey(key)) ?? false
+      if (wasRemoved) callListeners(key)
+      return wasRemoved
+    },
     set: (key, value) => {
       if (key === '') throw new Error('Cannot set a value for an empty key!')
       storage().setItem(prefixedKey(key), value.toString())
+      callListeners(key)
     },
     getString: (key) => storage().getItem(prefixedKey(key)) ?? undefined,
     getNumber: (key) => {