From 19bd90978b942f6b5aa61a407288af1df83a740a Mon Sep 17 00:00:00 2001
From: Amir Panahandeh <amirpanahandeh@yahoo.com>
Date: Wed, 20 Sep 2023 09:40:00 +0330
Subject: [PATCH] Update isDataOnlyNewLines and add tests

---
 packages/fleather/lib/src/widgets/controller.dart | 11 +++++------
 packages/fleather/lib/util.dart                   |  4 ++--
 packages/fleather/test/util_test.dart             | 10 ++++++++++
 3 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/packages/fleather/lib/src/widgets/controller.dart b/packages/fleather/lib/src/widgets/controller.dart
index 55aa09f2..b603c6d1 100644
--- a/packages/fleather/lib/src/widgets/controller.dart
+++ b/packages/fleather/lib/src/widgets/controller.dart
@@ -78,12 +78,11 @@ class FleatherController extends ChangeNotifier {
       }
       // special case for AutoTextDirectionRule
       if (delta.length <= 3 && delta.last.isRetain) {
-        return delta.last.attributes
-                    ?.containsKey(ParchmentAttribute.direction.key) ==
-                true &&
-            delta.last.attributes
-                    ?.containsKey(ParchmentAttribute.alignment.key) ==
-                true;
+        return delta.last.attributes != null &&
+            delta.last.attributes!
+                .containsKey(ParchmentAttribute.direction.key) &&
+            delta.last.attributes!
+                .containsKey(ParchmentAttribute.alignment.key);
       }
     }
     return false;
diff --git a/packages/fleather/lib/util.dart b/packages/fleather/lib/util.dart
index 7ba23a76..0c548a6a 100644
--- a/packages/fleather/lib/util.dart
+++ b/packages/fleather/lib/util.dart
@@ -55,6 +55,6 @@ TextDirection getDirectionOfNode(StyledNode node) {
 }
 
 bool isDataOnlyNewLines(Object data) {
-  if (data is! String) return false;
-  return data.replaceAll('\n', '').isEmpty;
+  if (data is! String || data.isEmpty) return false;
+  return RegExp('^(\n)+\$').hasMatch(data);
 }
diff --git a/packages/fleather/test/util_test.dart b/packages/fleather/test/util_test.dart
index e043ee74..e8c7108d 100644
--- a/packages/fleather/test/util_test.dart
+++ b/packages/fleather/test/util_test.dart
@@ -40,4 +40,14 @@ void main() {
       expect(result, 1);
     });
   });
+
+  test('isDataOnlyNewLines', () {
+    expect(isDataOnlyNewLines(123), false);
+    expect(isDataOnlyNewLines(Object()), false);
+    expect(isDataOnlyNewLines(''), false);
+    expect(isDataOnlyNewLines('\nTest\nTest\n'), false);
+    expect(isDataOnlyNewLines('\n \n\n'), false);
+    expect(isDataOnlyNewLines('\n\t\n\n'), false);
+    expect(isDataOnlyNewLines('\n\n\n'), true);
+  });
 }