to keep ids in 32-bit range

Author: yash-agarwa-l

dart/packages/fory-test/test/datatype_test/enum_serializer_test.dart

@@ -187,5 +187,22 @@ void main() {
       final ByteReader reader = ByteReader.forBytes(writer.takeBytes());
       check(reader.readVarUint32Small7()).equals(1);
     });
+
+    test('throws when enum id is outside unsigned 32-bit range', () {
+      final EnumSerializer serializer = EnumSerializer(false, [
+        EnumWithIds.A,
+      ], {
+        -1: EnumWithIds.A,
+      });
+
+      final ByteWriter writer = ByteWriter();
+      check(
+        () => serializer.write(
+          writer,
+          EnumWithIds.A,
+          _newSerializationContext(),
+        ),
+      ).throws<RangeError>();
+    });
   });
 }

dart/packages/fory/lib/src/codegen/analyze/impl/struct/enum_analyzer_impl.dart

@@ -26,6 +26,9 @@ import 'package:fory/src/codegen/meta/impl/enum_spec_generator.dart';
 class EnumAnalyzerImpl implements EnumAnalyzer {
   const EnumAnalyzerImpl();
 
+  static const int _minEnumId = 0;
+  static const int _maxEnumId = (1024 * 1024 * 1024 * 4) - 1; // 2^32 - 1
+
   /// Finds a non-constant field annotated with @ForyEnumId().
   String? _findIdField(EnumElement enumElement) {
     for (final FieldElement field in enumElement.fields) {
@@ -69,6 +72,7 @@ class EnumAnalyzerImpl implements EnumAnalyzer {
     final Map<int, String> usedIds = <int, String>{};
     final List<String> duplicateIds = <String>[];
     final List<String> missingIdValues = <String>[];
+    final List<String> outOfRangeIds = <String>[];
 
     for (final FieldElement enumField in enumFields) {
       final int? id = idFieldName != null
@@ -80,6 +84,11 @@ class EnumAnalyzerImpl implements EnumAnalyzer {
         continue;
       }
 
+      if (id < _minEnumId || id > _maxEnumId) {
+        outOfRangeIds.add('$id for ${enumField.name}');
+        continue;
+      }
+
       final String? firstValueWithId = usedIds[id];
       if (firstValueWithId != null) {
         duplicateIds.add('$id for $firstValueWithId and ${enumField.name}');
@@ -90,7 +99,7 @@ class EnumAnalyzerImpl implements EnumAnalyzer {
     }
 
     final bool useAnnotatedIds =
-        missingIdValues.isEmpty && duplicateIds.isEmpty;
+      missingIdValues.isEmpty && duplicateIds.isEmpty && outOfRangeIds.isEmpty;
     final bool hasAnyAnnotatedIds = enumIds.isNotEmpty;
     if (hasAnyAnnotatedIds && !useAnnotatedIds) {
       if (missingIdValues.isNotEmpty) {
@@ -107,6 +116,14 @@ class EnumAnalyzerImpl implements EnumAnalyzer {
           'All @ForyEnumId annotations are ignored and ordinal serialization is used.',
         );
       }
+      if (outOfRangeIds.isNotEmpty) {
+        print(
+          '[WARNING] Enum $enumName in $packageName has @ForyEnumId values outside the '
+          'unsigned 32-bit range (0 to 4294967295). '
+          'Offending values: ${outOfRangeIds.join('; ')}. '
+          'All @ForyEnumId annotations are ignored and ordinal serialization is used.',
+        );
+      }
     }
 
     return EnumSpecGenerator(

dart/packages/fory/lib/src/serializer/enum_serializer.dart

@@ -50,6 +50,9 @@ final class _EnumSerializerCache extends SerializerCache {
 final class EnumSerializer extends CustomSerializer<Enum> {
   static const SerializerCache cache = _EnumSerializerCache();
 
+  static const int _minEnumId = 0;
+  static const int _maxEnumId = (1024 * 1024 * 1024 * 4) - 1; // 2^32 - 1
+
   final List<Enum> values;
   final Map<int, Enum>? _idToValue;
   final Map<Enum, int>? _valueToId;
@@ -101,6 +104,15 @@ final class EnumSerializer extends CustomSerializer<Enum> {
           'Enum value is missing from EnumSpec.idToValue mapping.',
         );
       }
+      if (id < _minEnumId || id > _maxEnumId) {
+        throw RangeError.range(
+          id,
+          _minEnumId,
+          _maxEnumId,
+          'id',
+          'Enum id must be within unsigned 32-bit range.',
+        );
+      }
       bw.writeVarUint32Small7(id);
       return;
     }