Merge branch 'main' of https://github.com/sitatec/firebase_database_m…

…ocks into main

README.md

@@ -1,10 +1,76 @@
 # firebase_database_mocks
+Fakes to write unit tests for FirebaseDatabase (real-time database). Get Instance
+`MockFirebaseDatabase.instance`, then pass it around your project as if it were a
+`FirebaseDatabase.instance`. This mock keep data in memory while test running.
 
-A new Flutter project.
+## Usage
+```dart
+import 'package:firebase_database/firebase_database.dart';
+import 'package:firebase_database_mocks/firebase_database_mocks.dart';
+import 'package:flutter_test/flutter_test.dart';
 
-## Getting Started
+class UserRepository {
+  UserRepository(this.firebaseDatabase);
+  FirebaseDatabase firebaseDatabase;
 
-This project is a starting point for a Flutter application.
+  Future<String> getUserName(String userId) async {
+    final userNameReference =
+        firebaseDatabase.reference().child('users').child(userId).child('name');
+    final dataSnapshot = await userNameReference.once();
+    return dataSnapshot.value;
+  }
+
+  Future<Map<String, dynamic>> getUser(String userId) async {
+    final userNode = firebaseDatabase.reference().child('users/$userId');
+    final dataSnapshot = await userNode.once();
+    return dataSnapshot.value;
+  }
+}
+
+void main() {
+  FirebaseDatabase firebaseDatabase;
+  UserRepository userRepository;
+  // Put fake data
+  const userId = 'userId';
+  const userName = 'Elon musk';
+  const fakeData = {
+    'users': {
+      userId: {
+        'name': userName,
+        'email': '[email protected]',
+        'photoUrl': 'url-to-photo.jpg',
+      },
+      'otherUserId': {
+        'name': 'userName',
+        'email': '[email protected]',
+        'photoUrl': 'other_url-to-photo.jpg',
+      }
+    }
+  };
+  MockFirebaseDatabase.instance.reference().set(fakeData);
+  setUp(() {
+    firebaseDatabase = MockFirebaseDatabase.instance;
+    userRepository = UserRepository(firebaseDatabase);
+  });
+  test('Should get userName ...', () async {
+    final userNameFromFakeDatabase = await userRepository.getUserName(userId);
+    expect(userNameFromFakeDatabase, equals(userName));
+  });
+
+  test('Should get user ...', () async {
+    final userNameFromFakeDatabase = await userRepository.getUser(userId);
+    expect(
+      userNameFromFakeDatabase,
+      equals({
+        'name': userName,
+        'email': '[email protected]',
+        'photoUrl': 'url-to-photo.jpg',
+      }),
+    );
+  });
+}
+
+```
 
 A few resources to get you started if this is your first Flutter project: