Merge pull request #708 from GetStream/add-filter

feat(llc): added not exists filter

docusaurus/docs/Flutter/guides/understanding_filters.mdx

@@ -104,7 +104,16 @@ Filter.autoComplete('name', 'demo')
 The 'exists' filter matches values that exist, or don't exist, based on the specified boolean value.
 
 ```dart
-Filter.exists('name', true)
+Filter.exists('name')
+```
+
+#### Filter.notExists
+
+The 'notExists' filter checks if the specified key doesn't exist. This is a simplified call to `Filter.exists`
+with the value set to false.
+
+```dart
+Filter.notExists('name')
 ```
 
 #### Filter.contains

packages/stream_chat/CHANGELOG.md

@@ -1,5 +1,9 @@
 ## Upcoming
 
+✅ Added
+
+- Added `Filter.notExists`.
+
 🐞 Fixed
 
 - [[#710]](https://github.com/GetStream/stream-chat-flutter/issues/710) Fixed JWT requiring using `String` as id.

packages/stream_chat/lib/src/core/models/filter.dart

@@ -167,6 +167,9 @@ class Filter extends Equatable {
   factory Filter.exists(String key, {bool exists = true}) =>
       Filter._(operator: FilterOperator.exists, key: key, value: exists);
 
+  /// Matches values that don't exist.
+  factory Filter.notExists(String key) => Filter.exists(key, exists: false);
+
   /// Matches any list that contains the specified values
   factory Filter.contains(String key, Object value) =>
       Filter._(operator: FilterOperator.contains, key: key, value: value);

packages/stream_chat/test/src/core/models/filter_test.dart

@@ -114,7 +114,7 @@ void main() {
 
     test('notExists', () {
       const key = 'testKey';
-      final filter = Filter.exists(key, exists: false);
+      final filter = Filter.notExists(key);
       expect(filter.key, key);
       expect(filter.value, isFalse);
       expect(filter.operator, FilterOperator.exists.rawValue);