From 5a13f622cf41383f8c14e21149309ce9bc5c366e Mon Sep 17 00:00:00 2001
From: Will Hughes <insertjokehere@users.noreply.github.com>
Date: Wed, 23 Mar 2022 17:56:14 +1300
Subject: [PATCH] Correctly parse lists of enums in Dart generated code (#7157)

* Correctly parse lists of enums in Dart generated code

* Add a test for #6869

* Commit generated code

* Fixed missing newline-at-eof
---
 dart/test/flat_buffers_test.dart              | 16 +++++++++++++++
 dart/test/list_of_enums.fbs                   | 10 ++++++++++
 src/idl_gen_dart.cpp                          | 20 ++++++++++++++++++-
 tests/DartTest.sh                             |  2 ++
 ...onster_test_my_game.example_generated.dart |  2 +-
 5 files changed, 48 insertions(+), 2 deletions(-)
 create mode 100644 dart/test/list_of_enums.fbs

diff --git a/dart/test/flat_buffers_test.dart b/dart/test/flat_buffers_test.dart
index 8cee6b281..04875a0bc 100644
--- a/dart/test/flat_buffers_test.dart
+++ b/dart/test/flat_buffers_test.dart
@@ -13,6 +13,7 @@ import 'package:test_reflective_loader/test_reflective_loader.dart';
 
 import './monster_test_my_game.example_generated.dart' as example;
 import './monster_test_my_game.example2_generated.dart' as example2;
+import './list_of_enums_generated.dart' as example3;
 
 main() {
   defineReflectiveSuite(() {
@@ -20,6 +21,7 @@ main() {
     defineReflectiveTests(ObjectAPITest);
     defineReflectiveTests(CheckOtherLangaugesData);
     defineReflectiveTests(GeneratorTest);
+    defineReflectiveTests(ListOfEnumsTest);
   });
 }
 
@@ -902,3 +904,17 @@ class GeneratorTest {
         same(example.AnyAmbiguousAliasesTypeId.values));
   }
 }
+
+// See #6869
+@reflectiveTest
+class ListOfEnumsTest {
+  void test_listOfEnums() async {
+    var mytable = example3.MyTableObjectBuilder(
+      options: [example3.OptionsEnum.A, example3.OptionsEnum.B, example3.OptionsEnum.C]);
+    var bytes = mytable.toBytes();
+    var mytable_read = example3.MyTable(bytes);
+    expect(mytable_read.options![0].value, example3.OptionsEnum.A.value);
+    expect(mytable_read.options![1].value, example3.OptionsEnum.B.value);
+    expect(mytable_read.options![2].value, example3.OptionsEnum.C.value);
+  }
+}
diff --git a/dart/test/list_of_enums.fbs b/dart/test/list_of_enums.fbs
new file mode 100644
index 000000000..a4272a43b
--- /dev/null
+++ b/dart/test/list_of_enums.fbs
@@ -0,0 +1,10 @@
+enum OptionsEnum : uint32
+{
+    A = 1,
+    B = 2,
+    C = 3
+}
+
+table MyTable {
+    options : [OptionsEnum];
+}
diff --git a/src/idl_gen_dart.cpp b/src/idl_gen_dart.cpp
index ff2c1a5d5..3b8660bfd 100644
--- a/src/idl_gen_dart.cpp
+++ b/src/idl_gen_dart.cpp
@@ -308,7 +308,7 @@ class DartGenerator : public BaseGenerator {
             "> {\n";
     code += "  const _" + name + "Reader();\n\n";
     code += "  @override\n";
-    code += "  int get size => 1;\n\n";
+    code += "  int get size => " + EnumSize(enum_def.underlying_type) + ";\n\n";
     code += "  @override\n";
     code +=
         "  " + name + " read(" + _kFb + ".BufferContext bc, int offset) =>\n";
@@ -339,6 +339,24 @@ class DartGenerator : public BaseGenerator {
     }
   }
 
+  static std::string EnumSize(const Type &type) {
+    switch (type.base_type) {
+      case BASE_TYPE_BOOL:
+      case BASE_TYPE_CHAR:
+      case BASE_TYPE_UTYPE:
+      case BASE_TYPE_UCHAR: return "1";
+      case BASE_TYPE_SHORT:
+      case BASE_TYPE_USHORT: return "2";
+      case BASE_TYPE_INT:
+      case BASE_TYPE_UINT:
+      case BASE_TYPE_FLOAT: return "4";
+      case BASE_TYPE_LONG:
+      case BASE_TYPE_ULONG:
+      case BASE_TYPE_DOUBLE: return "8";
+      default: return "1";
+    }
+  }
+
   std::string GenReaderTypeName(const Type &type, Namespace *current_namespace,
                                 const FieldDef &def,
                                 bool parent_is_vector = false, bool lazy = true,
diff --git a/tests/DartTest.sh b/tests/DartTest.sh
index 36d1b1495..653f77720 100755
--- a/tests/DartTest.sh
+++ b/tests/DartTest.sh
@@ -25,6 +25,8 @@ cp monster_test.fbs ../dart/test
 
 cd ../dart
 
+../flatc --dart --gen-object-api -o ./test ./test/list_of_enums.fbs
+
 # update packages
 dart pub get
 # Execute the sample.
diff --git a/tests/monster_test_my_game.example_generated.dart b/tests/monster_test_my_game.example_generated.dart
index dd816d97b..4c9557368 100644
--- a/tests/monster_test_my_game.example_generated.dart
+++ b/tests/monster_test_my_game.example_generated.dart
@@ -152,7 +152,7 @@ class _LongEnumReader extends fb.Reader<LongEnum> {
   const _LongEnumReader();
 
   @override
-  int get size => 1;
+  int get size => 8;
 
   @override
   LongEnum read(fb.BufferContext bc, int offset) =>