protobuf: simplify test package

recipes/protobuf/all/test_package/CMakeLists.txt

@@ -4,7 +4,7 @@ project(test_package LANGUAGES CXX)
 
 find_package(protobuf CONFIG REQUIRED)
 
-add_executable(${PROJECT_NAME} test_package.cpp addressbook.proto)
+add_executable(${PROJECT_NAME} test_package.cpp)
 target_compile_features(${PROJECT_NAME} PRIVATE cxx_std_11)
 target_include_directories(${PROJECT_NAME} PRIVATE "${CMAKE_CURRENT_BINARY_DIR}")
 if (protobuf_LITE)
@@ -17,5 +17,3 @@ if(TARGET protobuf::libprotoc)
     target_link_libraries(${PROJECT_NAME} PRIVATE protobuf::libprotoc)
 endif()
 
-protobuf_generate_cpp(PROTO_SRCS PROTO_HDRS TARGET ${PROJECT_NAME})
-protobuf_generate(LANGUAGE cpp TARGET ${PROJECT_NAME} PROTOS addressbook.proto)

recipes/protobuf/all/test_package/conanfile.py

@@ -13,10 +13,8 @@ def layout(self):
         cmake_layout(self)
 
     def requirements(self):
-        self.requires(self.tested_reference_str)
-
-    def build_requirements(self):
-        self.tool_requires(self.tested_reference_str)
+        # note `run=True` so that the runenv can find protoc
+        self.requires(self.tested_reference_str, run=True)
 
     def generate(self):
         tc = CMakeToolchain(self)
@@ -32,3 +30,8 @@ def test(self):
         if can_run(self):
             bin_path = os.path.join(self.cpp.build.bindirs[0], "test_package")
             self.run(bin_path, env="conanrun")
+
+            # Invoke protoc in the same way CMake would
+            self.run(f"protoc --proto_path={self.source_folder} --cpp_out={self.build_folder} {self.source_folder}/addressbook.proto", env="conanrun")
+            assert os.path.exists(os.path.join(self.build_folder,"addressbook.pb.cc"))
+            assert os.path.exists(os.path.join(self.build_folder,"addressbook.pb.h"))

recipes/protobuf/all/test_package/test_package.cpp

@@ -1,17 +1,15 @@
 #include <cstdlib>
 #include <iostream>
 
-#include "addressbook.pb.h"
+#include <google/protobuf/timestamp.pb.h>
+#include <google/protobuf/util/time_util.h>
 
 int main()
 {
-	std::cout << "Bincrafters\n";
+	google::protobuf::Timestamp ts;
+	google::protobuf::util::TimeUtil::FromString("1972-01-01T10:00:20.021Z", &ts);
+	const auto nanoseconds = ts.nanos();
 
-	tutorial::Person p;
-	p.set_id(21);
-	p.set_name("conan-center-index");
-	p.set_email("info@conan.io");
-
-	std::cout << p.SerializeAsString() << "\n";
+	std::cout << nanoseconds << "\n";
 	return EXIT_SUCCESS;
 }