feat(djangoflow_remote_config): Add mapExtensions (#71)

- Add `removeNullAndCast` to `Map<String, dynamic>`
- Add tests
- Add export

packages/djangoflow_remote_config/lib/djangoflow_remote_config.dart

@@ -6,3 +6,4 @@ export 'src/data/models/app_launch_details/app_launch_details.dart';
 export 'src/presentation/remote_config_part_updater.dart';
 export 'src/configuration/constants.dart';
 export 'src/utils/remote_config_extensions.dart';
+export 'src/utils/map_extensions.dart';

packages/djangoflow_remote_config/lib/src/utils/map_extensions.dart

@@ -0,0 +1,17 @@
+extension MapExtensions on Map<String, dynamic>? {
+  /// Removes all null values from the map and casts it to a Map<String, Object>
+  Map<String, Object>? removeNullAndCast() {
+    final Map<String, Object> newMap = {};
+    if (this == null || this!.isEmpty) {
+      return null;
+    } else {
+      this!.forEach((key, value) {
+        if (value != null) {
+          newMap[key] = value;
+        }
+      });
+
+      return newMap;
+    }
+  }
+}

packages/djangoflow_remote_config/test/utils/extensions/map_extensions_test.dart

@@ -0,0 +1,41 @@
+import 'package:djangoflow_remote_config/src/utils/map_extensions.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+void main() {
+  const Map<String, dynamic> testMap = {
+    'key1': 'value1',
+    'key2': 2,
+    'key3': null,
+  };
+
+  test('MapExtension returns null if map is null', () {
+    const Map<String, dynamic>? nullMap = null;
+    final Map<String, Object>? newMap = nullMap?.removeNullAndCast();
+
+    expect(newMap, null);
+  });
+
+  test('MapExtension returns null if map is empty', () {
+    const Map<String, dynamic> nullMap = {};
+    final Map<String, Object>? newMap = nullMap.removeNullAndCast();
+
+    expect(newMap, null);
+  });
+
+  test(
+    'MapExtension casts Map<String,dynamic> to Map<String, Object>',
+    () {
+      final Map<String, Object>? newMap = testMap.removeNullAndCast();
+      expect(newMap, isA<Map<String, Object>>());
+    },
+  );
+
+  test(
+    'MapExtension removes null values',
+    () {
+      final Map<String, Object>? newMap = testMap.removeNullAndCast();
+      expect(newMap?.containsValue(null), false);
+      expect(newMap, {'key1': 'value1', 'key2': 2});
+    },
+  );
+}