[pigeon] wrap encodable lists in encodable value before reply (#2968)

* wrap encodable lists before reply

* Changelog

* changelog

* basic test

* positive test and move

* nit

packages/pigeon/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 4.2.14
+
+* [c++] Fixes reply sending non EncodableValue wrapped lists.
+
 ## 4.2.13
 
 * Add documentation comment support for Enum members.

packages/pigeon/lib/cpp_generator.dart

@@ -590,7 +590,7 @@ const flutter::StandardMessageCodec& ${api.name}::GetCodec() {
                     indent.write('if ($encodableArgName.IsNull()) ');
                     indent.scoped('{', '}', () {
                       indent.writeln(
-                          'reply(WrapError("$argName unexpectedly null."));');
+                          'reply(flutter::EncodableValue(WrapError("$argName unexpectedly null.")));');
                       indent.writeln('return;');
                     });
                   }
@@ -656,7 +656,7 @@ $prefix\t}${indent.newline}''';
               if (method.isAsynchronous) {
                 methodArgument.add(
                   '[&wrapped, &reply]($returnTypeName&& output) {${indent.newline}'
-                  '${wrapResponse('\treply(wrapped);${indent.newline}', method.returnType)}'
+                  '${wrapResponse('\treply(flutter::EncodableValue(std::move(wrapped)));${indent.newline}', method.returnType)}'
                   '}',
                 );
               }
@@ -673,11 +673,13 @@ $prefix\t}${indent.newline}''';
             indent.scoped('{', '}', () {
               indent.writeln('wrapped = WrapError(exception.what());');
               if (method.isAsynchronous) {
-                indent.writeln('reply(wrapped);');
+                indent.writeln(
+                    'reply(flutter::EncodableValue(std::move(wrapped)));');
               }
             });
             if (!method.isAsynchronous) {
-              indent.writeln('reply(wrapped);');
+              indent.writeln(
+                  'reply(flutter::EncodableValue(std::move(wrapped)));');
             }
           });
         });

packages/pigeon/lib/generator_tools.dart

@@ -9,7 +9,7 @@ import 'dart:mirrors';
 import 'ast.dart';
 
 /// The current version of pigeon. This must match the version in pubspec.yaml.
-const String pigeonVersion = '4.2.13';
+const String pigeonVersion = '4.2.14';
 
 /// Read all the content from [stdin] to a String.
 String readStdin() {

packages/pigeon/pubspec.yaml

@@ -2,7 +2,7 @@ name: pigeon
 description: Code generator tool to make communication between Flutter and the host platform type-safe and easier.
 repository: https://github.com/flutter/packages/tree/main/packages/pigeon
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3Apigeon
-version: 4.2.13 # This must match the version in lib/generator_tools.dart
+version: 4.2.14 # This must match the version in lib/generator_tools.dart
 
 environment:
   sdk: ">=2.12.0 <3.0.0"

packages/pigeon/test/cpp_generator_test.dart

@@ -1203,4 +1203,74 @@ void main() {
     final String code = sink.toString();
     expect(code, contains(' : public flutter::StandardCodecSerializer'));
   });
+
+  test('Does not send unwrapped EncodableLists', () {
+    final Root root = Root(apis: <Api>[
+      Api(name: 'Api', location: ApiLocation.host, methods: <Method>[
+        Method(
+          name: 'doSomething',
+          arguments: <NamedType>[
+            NamedType(
+                name: 'aBool',
+                type: const TypeDeclaration(
+                  baseName: 'bool',
+                  isNullable: false,
+                )),
+            NamedType(
+                name: 'anInt',
+                type: const TypeDeclaration(
+                  baseName: 'int',
+                  isNullable: false,
+                )),
+            NamedType(
+                name: 'aString',
+                type: const TypeDeclaration(
+                  baseName: 'String',
+                  isNullable: false,
+                )),
+            NamedType(
+                name: 'aList',
+                type: const TypeDeclaration(
+                  baseName: 'List',
+                  typeArguments: <TypeDeclaration>[
+                    TypeDeclaration(baseName: 'Object', isNullable: true)
+                  ],
+                  isNullable: false,
+                )),
+            NamedType(
+                name: 'aMap',
+                type: const TypeDeclaration(
+                  baseName: 'Map',
+                  typeArguments: <TypeDeclaration>[
+                    TypeDeclaration(baseName: 'String', isNullable: true),
+                    TypeDeclaration(baseName: 'Object', isNullable: true),
+                  ],
+                  isNullable: false,
+                )),
+            NamedType(
+                name: 'anObject',
+                type: const TypeDeclaration(
+                  baseName: 'ParameterObject',
+                  isNullable: false,
+                )),
+          ],
+          returnType: const TypeDeclaration.voidDeclaration(),
+        ),
+      ])
+    ], classes: <Class>[
+      Class(name: 'ParameterObject', fields: <NamedType>[
+        NamedType(
+            type: const TypeDeclaration(
+              baseName: 'bool',
+              isNullable: false,
+            ),
+            name: 'aValue'),
+      ]),
+    ], enums: <Enum>[]);
+    final StringBuffer sink = StringBuffer();
+    generateCppSource(const CppOptions(), root, sink);
+    final String code = sink.toString();
+    expect(code, isNot(contains('reply(wrap')));
+    expect(code, contains('reply(flutter::EncodableValue('));
+  });
 }