🐛 fix ljharb/qs#493

lib/src/extensions/decode.dart

@@ -159,7 +159,10 @@ extension _$Decode on QS {
         : givenKey!;
 
     // The regex chunks
-    final RegExp brackets = RegExp(r'(\[[^[\]]*])');
+    final RegExp brackets = RecursiveRegex(
+      startDelimiter: '[',
+      endDelimiter: ']',
+    );
 
     // Get the parent
     Match? segment = options.depth > 0 ? brackets.firstMatch(key) : null;
@@ -178,7 +181,7 @@ extension _$Decode on QS {
         i < options.depth) {
       i += 1;
       if (segment != null) {
-        keys.add(segment.group(1)!);
+        keys.add(segment.group(0)!);
         // Update the key to start searching from the next position
         key = key.slice(segment.end);
       }

lib/src/qs.dart

@@ -10,6 +10,7 @@ import 'package:qs_dart/src/models/decode_options.dart';
 import 'package:qs_dart/src/models/encode_options.dart';
 import 'package:qs_dart/src/models/undefined.dart';
 import 'package:qs_dart/src/utils.dart';
+import 'package:recursive_regex/recursive_regex.dart';
 import 'package:weak_map/weak_map.dart';
 
 part 'extensions/decode.dart';

pubspec.yaml

@@ -10,6 +10,7 @@ dependencies:
   collection: ^1.18.0
   equatable: ^2.0.5
   meta: ^1.9.1
+  recursive_regex: ^1.0.0
   weak_map: ^3.0.1
 
 dev_dependencies:

test/unit/fixed_qs_issues_test.dart

@@ -0,0 +1,19 @@
+import 'package:qs_dart/qs_dart.dart';
+import 'package:test/test.dart';
+
+void main() {
+  group('fixed ljharb/qs issues', () {
+    test('ljharb/qs#493', () {
+      final Map<String, dynamic> original = {
+        'search': {'withbracket[]': 'foobar'}
+      };
+      final String encoded = 'search[withbracket[]]=foobar';
+
+      expect(
+        QS.encode(original, EncodeOptions(encode: false)),
+        equals(encoded),
+      );
+      expect(QS.decode(encoded), equals(original));
+    });
+  });
+}