fix(database, web): more explicit interop types

packages/firebase_database/firebase_database_web/lib/src/interop/data_snapshot_interop.dart

@@ -4,12 +4,7 @@
 
 part of 'database_interop.dart';
 
-@JS('DataSnapshot')
-@staticInterop
-@anonymous
-abstract class DataSnapshotJsImpl {}
-
-extension DataSnapshotJsImpl$ on DataSnapshotJsImpl {
+extension type DataSnapshotJsImpl._(JSObject _) implements JSObject {
   external JSString? get key;
 
   external JSAny? /* JSString | num | null*/ get priority;

packages/firebase_database/firebase_database_web/lib/src/interop/database.dart

@@ -78,8 +78,7 @@ class Database
 /// can be used for reading or writing data to that database location.
 ///
 /// See: <https://firebase.google.com/docs/reference/js/firebase.database.Reference>.
-class DatabaseReference<T extends database_interop.ReferenceJsImpl>
-    extends Query<T> {
+class DatabaseReference extends Query<database_interop.ReferenceJsImpl> {
   static final _expando = Expando<DatabaseReference>();
 
   /// The last part of the current path.
@@ -204,11 +203,9 @@ class DatabaseReference<T extends database_interop.ReferenceJsImpl>
                 applyLocally: applyLocally.toJS),
           )
           .toDart;
-      final castedJsTransaction =
-          jsTransactionResult as database_interop.TransactionResultJsImpl;
       return Transaction(
-        committed: (castedJsTransaction.committed).toDart,
-        snapshot: DataSnapshot._fromJsObject(castedJsTransaction.snapshot),
+        committed: (jsTransactionResult.committed).toDart,
+        snapshot: DataSnapshot._fromJsObject(jsTransactionResult.snapshot),
       );
     } catch (e, s) {
       throw convertFirebaseDatabaseException(e, s);
@@ -317,8 +314,7 @@ class Query<T extends database_interop.QueryJsImpl> extends JsObjectWrapper<T> {
     final jsSnapshotPromise = database_interop.get(jsObject);
     final snapshot = await jsSnapshotPromise.toDart;
 
-    return DataSnapshot.getInstance(
-        snapshot as database_interop.DataSnapshotJsImpl);
+    return DataSnapshot.getInstance(snapshot);
   }
 
   /// Returns a Query with the ending point [value]. The ending point
@@ -674,18 +670,18 @@ class OnDisconnect
 /// [Future] property.
 ///
 /// See: <https://firebase.google.com/docs/reference/js/firebase.database.ThenableReference>.
-class ThenableReference
-    extends DatabaseReference<database_interop.ThenableReferenceJsImpl> {
-  late final Future<DatabaseReference> _future = jsObject
-      .then(((database_interop.ReferenceJsImpl reference) {
-        DatabaseReference.getInstance(reference);
-      }).toJS)
-      .toDart
-      .then((value) => value as DatabaseReference);
+class ThenableReference extends DatabaseReference {
+  late final Future<DatabaseReference> _future =
+      (jsObject as database_interop.ThenableReferenceJsImpl)
+          .then(((database_interop.ReferenceJsImpl reference) {
+            DatabaseReference.getInstance(reference);
+          }).toJS)
+          .toDart
+          .then((value) => value as DatabaseReference);
 
   /// Creates a new ThenableReference from a [jsObject].
   ThenableReference.fromJsObject(
-    super.jsObject,
+    database_interop.ThenableReferenceJsImpl super.jsObject,
   ) : super._fromJsObject();
 
   /// A Future property.

packages/firebase_database/firebase_database_web/lib/src/interop/database_interop.dart

@@ -50,7 +50,7 @@ external void forceWebSockets();
 
 @JS()
 @staticInterop
-external JSPromise /*DataSnapshotJsImpl*/ get(QueryJsImpl query);
+external JSPromise<DataSnapshotJsImpl> get(QueryJsImpl query);
 
 @JS()
 @staticInterop
@@ -164,13 +164,13 @@ external ReferenceJsImpl refFromURL(
 
 @JS()
 @staticInterop
-external JSPromise remove(
+external JSPromise<ReferenceJsImpl> remove(
   ReferenceJsImpl ref,
 );
 
 @JS()
 @staticInterop
-external JSPromise/*<TransactionResultJsImpl>*/ runTransaction(
+external JSPromise<TransactionResultJsImpl> runTransaction(
   ReferenceJsImpl ref,
   JSFunction transactionUpdate,
   // Function(JSAny currentData) transactionUpdate,
@@ -220,29 +220,17 @@ abstract class ServerValue {
   external static JSAny get TIMESTAMP;
 }
 
-@JS('Database')
-@staticInterop
-abstract class DatabaseJsImpl {}
-
-extension DatabaseJsImplExtension on DatabaseJsImpl {
+extension type DatabaseJsImpl._(JSObject _) implements JSObject {
   external AppJsImpl get app;
   external set app(AppJsImpl a);
   external JSString get type;
 }
 
-@JS('QueryConstraint')
-@staticInterop
-abstract class QueryConstraintJsImpl {}
-
-extension QueryConstraintJsImplExtension on QueryConstraintJsImpl {
+extension type QueryConstraintJsImpl._(JSObject _) implements JSObject {
   external JSString get type;
 }
 
-@JS('OnDisconnect')
-@staticInterop
-abstract class OnDisconnectJsImpl {}
-
-extension OnDisconnectJsImplExtension on OnDisconnectJsImpl {
+extension type OnDisconnectJsImpl._(JSObject _) implements JSObject {
   external JSPromise cancel([
     JSFunction onComplete,
     //void Function(JSAny) onComplete
@@ -269,11 +257,8 @@ extension OnDisconnectJsImplExtension on OnDisconnectJsImpl {
   );
 }
 
-@JS('ThenableReference')
-@staticInterop
-abstract class ThenableReferenceJsImpl extends ReferenceJsImpl {}
-
-extension ThenableReferenceJsImplExtension on ThenableReferenceJsImpl {
+extension type ThenableReferenceJsImpl._(JSObject _)
+    implements JSObject, ReferenceJsImpl {
   external JSPromise then([JSFunction? onResolve, JSFunction? onReject]);
 }
 
@@ -302,12 +287,7 @@ abstract class ListenOptions {
   external static JSBoolean get onlyOnce;
 }
 
-@JS()
-@staticInterop
-@anonymous
-abstract class FirebaseError {}
-
-extension FirebaseErrorExtension on FirebaseError {
+extension type FirebaseError._(JSObject _) implements JSObject {
   external JSString get code;
   external JSString get message;
   external JSString get name;

packages/firebase_database/firebase_database_web/lib/src/interop/query_interop.dart

@@ -4,11 +4,7 @@
 
 part of 'database_interop.dart';
 
-@JS('Query')
-@staticInterop
-abstract class QueryJsImpl {}
-
-extension ExtensionQueryJsImpl on QueryJsImpl {
+extension type QueryJsImpl._(JSObject _) implements JSObject {
   external ReferenceJsImpl get ref;
 
   external JSBoolean isEqual(QueryJsImpl other);

packages/firebase_database/firebase_database_web/lib/src/interop/reference_interop.dart

@@ -4,21 +4,13 @@
 
 part of 'database_interop.dart';
 
-@JS('TransactionResult')
-@staticInterop
-abstract class TransactionResultJsImpl {}
-
-extension TransactionResultJsImplExtension on TransactionResultJsImpl {
+extension type TransactionResultJsImpl._(JSObject _) implements JSObject {
   external JSObject toJSON();
   external JSBoolean get committed;
   external DataSnapshotJsImpl get snapshot;
 }
 
-@JS('DatabaseReference')
-@staticInterop
-abstract class ReferenceJsImpl extends QueryJsImpl {}
-
-extension ReferenceJsImplExtension on ReferenceJsImpl {
+extension type ReferenceJsImpl._(JSObject _) implements JSObject, QueryJsImpl {
   external JSString? get key;
 
   external ReferenceJsImpl? get parent;