feat: Added tests and minor fixes

packages/stream_chat_flutter/lib/src/gradient_avatar.dart

@@ -47,7 +47,7 @@ class _GradientAvatarState extends State<GradientAvatar> {
     var result = '';
 
     for (var i = 0; i < parts.length; i++) {
-      result = result + parts[i][0];
+      result = result + parts[i][0].toUpperCase();
     }
 
     return result;
@@ -112,8 +112,8 @@ class DemoPainter extends CustomPainter {
 
     final textSize = smallerSide / 3;
 
-    final dxShift = (username.length == 2 ? 1.45 : 0.75) * textSize / 2;
+    final dxShift = (username.length == 2 ? 1.45 : 0.9) * textSize / 2;
-    final dyShift = (username.length == 2 ? 1.0 : 1.8) * textSize / 2;
+    final dyShift = (username.length == 2 ? 1.0 : 1.65) * textSize / 2;
 
     final fontSize = username.length == 2 ? textSize : textSize * 1.5;
 

packages/stream_chat_flutter/test/src/gradient_avatar_test.dart

@@ -0,0 +1,82 @@
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:golden_toolkit/golden_toolkit.dart';
+import 'package:mocktail/mocktail.dart';
+import 'package:stream_chat_flutter/src/gradient_avatar.dart';
+import 'package:stream_chat_flutter/stream_chat_flutter.dart';
+
+import 'mocks.dart';
+
+void main() {
+  testWidgets(
+    'control test',
+    (WidgetTester tester) async {
+      final client = MockClient();
+      final clientState = MockClientState();
+
+      when(() => client.state).thenReturn(clientState);
+      when(() => clientState.user).thenReturn(OwnUser(id: 'user-id'));
+
+      await tester.pumpWidget(
+        MaterialApp(
+          home: StreamChat(
+            client: client,
+            child: const Scaffold(
+              body: Center(
+                child: SizedBox(
+                  width: 50,
+                  height: 50,
+                  child: GradientAvatar(name: 'demo user', userId: 'demo123'),
+                ),
+              ),
+            ),
+          ),
+        ),
+      );
+
+      expect(find.byType(GradientAvatar), findsOneWidget);
+    },
+  );
+
+  testGoldens(
+    'golden test for the name "demo user"',
+    (WidgetTester tester) async {
+      await tester.pumpWidget(
+        const MaterialApp(
+          home: Scaffold(
+            body: Center(
+              child: SizedBox(
+                width: 50,
+                height: 50,
+                child: GradientAvatar(name: 'demo user', userId: 'demo123'),
+              ),
+            ),
+          ),
+        ),
+      );
+
+      await screenMatchesGolden(tester, 'gradient_avatar_0');
+    },
+  );
+
+  testGoldens(
+    'golden test for the name "demo"',
+        (WidgetTester tester) async {
+      await tester.pumpWidget(
+        const MaterialApp(
+          home: Scaffold(
+            body: Center(
+              child: SizedBox(
+                width: 50,
+                height: 50,
+                child: GradientAvatar(name: 'demo', userId: 'demo1'),
+              ),
+            ),
+          ),
+        ),
+      );
+
+      await screenMatchesGolden(tester, 'gradient_avatar_1');
+    },
+  );
+}