Add moveable_types=forward_setter option for perfect forwarding setters
Adds `forward_setter` value to `moveable_types` option, generating perfect forwarding setters for complex types while preserving traditional setters for primitives. Also fixes missing `operator<` implementation that caused link errors when structs are used as map keys.
**Forward Setter Generation** (`compiler/cpp/src/thrift/generate/t_cpp_generator.cc`):
- Parse `moveable_types=forward_setter` option
- Complex types (strings, containers, structs) → template setters with `std::forward<T_>`
- Primitive types → traditional const-ref setters
- Template implementations in `.tcc` file (auto-included in header)
- Legacy `moveable_types` behavior unchanged
**Compiler Unit Tests** (`compiler/cpp/tests/cpp/`):
- New `test_forward_setter.thrift` fixture
- Dedicated `t_cpp_generator_forward_setter_tests.cc` (91 assertions, 9 test cases)
- Verify `.tcc` generation and template implementations
**Integration Tests** (`test/cpp/src/`):
- `ForwardSetterTest.cpp` - validates lvalue/rvalue/temporary/literal setters with move semantics
- `PrivateOptionalTest.cpp` - SFINAE + static_assert verify optional fields are private
- `EnumClassTest.cpp` - type_traits + static_assert verify true enum class semantics
**CMakeLists.txt** (`test/cpp/`):
- Separate gen-cpp-{forward,private,enumclass} directories
**Makefile.am** (`test/cpp/`):
- Library targets for each option variant
- Proper `BUILT_SOURCES` dependencies
- Include path ordering: option-specific directory before standard `gen-cpp`
```cpp
// Generated with --gen cpp:moveable_types=forward_setter
struct TestStruct {
int32_t primitive_field;
std::string complex_field;
void __set_primitive_field(const int32_t val); // Traditional
template <typename T_>
void __set_complex_field(T_&& val); // Perfect forwarding
};
// In .tcc file:
template <typename T_>
void TestStruct::__set_complex_field(T_&& val) {
this->complex_field = ::std::forward<T_>(val);
__isset.complex_field = true;
}
```
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- [ ] If a ticket exists: Does your pull request title follow the pattern "THRIFT-NNNN: describe my issue"?
- [x] Did you squash your changes to a single commit? (not required, but preferred)
- [x] Did you do your best to avoid breaking changes? If one was needed, did you label the Jira ticket with "Breaking-Change"?
---------
Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: zsy056 <1074382+zsy056@users.noreply.github.com>
diff --git a/test/cpp/src/PrivateOptionalTest.cpp b/test/cpp/src/PrivateOptionalTest.cpp
new file mode 100644
index 0000000..82fa802
--- /dev/null
+++ b/test/cpp/src/PrivateOptionalTest.cpp
@@ -0,0 +1,137 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+/**
+ * Test file to verify that private_optional generated code compiles and works correctly.
+ * This exercises the private_optional option using ThriftTest types.
+ */
+
+#include <iostream>
+#include <string>
+#include <cassert>
+#include <type_traits>
+
+// Include generated thrift types with private_optional option
+#include "ThriftTest_types.h"
+
+using namespace thrift::test;
+
+// SFINAE test to check if a field is directly accessible
+template<typename T, typename = void>
+struct has_public_string_thing : std::false_type {};
+
+template<typename T>
+struct has_public_string_thing<T, decltype(void(std::declval<T>().string_thing))> : std::true_type {};
+
+// SFINAE test to check if optional field 'aa' is directly accessible
+template<typename T, typename = void>
+struct has_public_aa : std::false_type {};
+
+template<typename T>
+struct has_public_aa<T, decltype(void(std::declval<T>().aa))> : std::true_type {};
+
+// SFINAE test to check if required field 'ab' is directly accessible
+template<typename T, typename = void>
+struct has_public_ab : std::false_type {};
+
+template<typename T>
+struct has_public_ab<T, decltype(void(std::declval<T>().ab))> : std::true_type {};
+
+int main() {
+ std::cout << "Testing private_optional with ThriftTest types..." << std::endl;
+
+ // Compile-time verification: required fields should still be publicly accessible
+ static_assert(has_public_string_thing<Xtruct>::value,
+ "Required fields (like string_thing in Xtruct) should remain public");
+ std::cout << " ✓ Compile-time verification: Required fields are public (Xtruct)" << std::endl;
+
+ // Compile-time verification for StructB: optional field 'aa' should be private
+ static_assert(!has_public_aa<StructB>::value,
+ "Optional field 'aa' in StructB should be private with private_optional");
+ std::cout << " ✓ Compile-time verification: Optional field 'aa' is private (StructB)" << std::endl;
+
+ // Compile-time verification for StructB: required field 'ab' should be public
+ static_assert(has_public_ab<StructB>::value,
+ "Required field 'ab' in StructB should remain public");
+ std::cout << " ✓ Compile-time verification: Required field 'ab' is public (StructB)" << std::endl;
+
+ // Test 1: Verify getters work for accessing fields
+ {
+ Xtruct x;
+ x.__set_string_thing("test");
+ const std::string& str = x.__get_string_thing();
+ assert(str == "test");
+ std::cout << " ✓ Getter for string field works" << std::endl;
+ }
+
+ // Test 2: Verify setters work
+ {
+ Xtruct x;
+ x.__set_i32_thing(42);
+ x.__set_i64_thing(1234567890);
+ assert(x.__get_i32_thing() == 42);
+ assert(x.__get_i64_thing() == 1234567890);
+ std::cout << " ✓ Setters for primitive fields work" << std::endl;
+ }
+
+ // Test 3: Verify getters/setters for complex types
+ {
+ Xtruct2 x2;
+ Xtruct x;
+ x.__set_string_thing("nested");
+ x.__set_i32_thing(99);
+ x2.__set_struct_thing(x);
+ // With private_optional, use getters to access fields
+ assert(x2.__get_struct_thing().__get_string_thing() == "nested");
+ assert(x2.__get_struct_thing().__get_i32_thing() == 99);
+ std::cout << " ✓ Getters/setters for struct fields work" << std::endl;
+ }
+
+ // Test 4: Verify direct access to required fields still works
+ {
+ Xtruct x;
+ x.string_thing = "direct access";
+ x.i32_thing = 123;
+ assert(x.string_thing == "direct access");
+ assert(x.i32_thing == 123);
+ std::cout << " ✓ Direct access to required fields works" << std::endl;
+ }
+
+ // Test 5: Test StructB with optional and required fields
+ {
+ StructB sb;
+ StructA sa;
+ sa.__set_s("test struct");
+
+ // Set optional field 'aa' using setter (cannot access directly)
+ sb.__set_aa(sa);
+
+ // Set and access required field 'ab' directly (it's public)
+ sb.ab = sa;
+
+ // Verify using getters
+ assert(sb.__get_aa().__get_s() == "test struct");
+ assert(sb.ab.__get_s() == "test struct");
+ std::cout << " ✓ StructB: Optional field private, required field public" << std::endl;
+ }
+
+ std::cout << "\n✅ All private_optional tests passed!" << std::endl;
+ std::cout << " Verified at compile-time: Optional fields are private, required fields public" << std::endl;
+ return 0;
+}