Add custom test framework and code coverage support

- Move test framework from test/perf/ to test/ for shared use
- Add GTest-compatible macros (TEST, TEST_F, EXPECT_*, ASSERT_*, etc.)
- Remove GTest dependency from CMakeLists.txt
- Add test_framework library for unit and mp_unit tests
- Add code coverage support with lcov (MSCCLPP_ENABLE_COVERAGE option)
- Update perf tests to use shared framework

Co-authored-by: chhwang <8018170+chhwang@users.noreply.github.com>

Author: Copilot

CMakeLists.txt

@@ -56,6 +56,7 @@ option(MSCCLPP_USE_ROCM "Use AMD/ROCm." OFF)
 option(MSCCLPP_USE_IB "Use InfiniBand." ON)
 option(MSCCLPP_BYPASS_GPU_CHECK "Bypass GPU check." OFF)
 option(MSCCLPP_NPKIT_FLAGS "Set NPKIT flags" OFF)
+option(MSCCLPP_ENABLE_COVERAGE "Enable code coverage" OFF)
 set(MSCCLPP_GPU_ARCHS "" CACHE STRING "Specify GPU architectures with delimiters (comma, space, or semicolon).")
 
 if(MSCCLPP_BYPASS_GPU_CHECK)
@@ -98,6 +99,69 @@ else()
         message(FATAL_ERROR "No compatible GPU found. Set MSCCLPP_USE_CUDA or MSCCLPP_USE_ROCM to ON.")
     endif()
 endif()
+
+# Code coverage setup
+if(MSCCLPP_ENABLE_COVERAGE)
+    if(NOT CMAKE_BUILD_TYPE STREQUAL "Debug")
+        message(WARNING "Code coverage results with an optimized (non-Debug) build may be misleading")
+    endif()
+    
+    if(CMAKE_CXX_COMPILER_ID MATCHES "GNU|Clang")
+        message(STATUS "Code coverage enabled")
+        
+        # Add coverage flags to all targets
+        add_compile_options(--coverage -O0 -g)
+        add_link_options(--coverage)
+        
+        # Find lcov
+        find_program(LCOV_PATH lcov)
+        find_program(GENHTML_PATH genhtml)
+        
+        if(NOT LCOV_PATH)
+            message(WARNING "lcov not found. Install lcov to generate coverage reports.")
+        endif()
+        
+        if(NOT GENHTML_PATH)
+            message(WARNING "genhtml not found. Install lcov to generate HTML coverage reports.")
+        endif()
+        
+        if(LCOV_PATH AND GENHTML_PATH)
+            # Add coverage target
+            add_custom_target(coverage
+                COMMAND ${CMAKE_COMMAND} -E echo "Removing old coverage data..."
+                COMMAND ${LCOV_PATH} --directory . --zerocounters
+                
+                COMMAND ${CMAKE_COMMAND} -E echo "Running tests..."
+                COMMAND ${CMAKE_CTEST_COMMAND} --output-on-failure
+                
+                COMMAND ${CMAKE_COMMAND} -E echo "Collecting coverage data..."
+                COMMAND ${LCOV_PATH} --directory . --capture --output-file coverage.info
+                
+                COMMAND ${CMAKE_COMMAND} -E echo "Filtering coverage data..."
+                COMMAND ${LCOV_PATH} --remove coverage.info '/usr/*' '*/test/*' '*/build/*' --output-file coverage.info
+                
+                COMMAND ${CMAKE_COMMAND} -E echo "Generating HTML report..."
+                COMMAND ${GENHTML_PATH} coverage.info --output-directory coverage_html
+                
+                COMMAND ${CMAKE_COMMAND} -E echo "Coverage report generated in coverage_html/index.html"
+                
+                WORKING_DIRECTORY ${CMAKE_BINARY_DIR}
+                COMMENT "Generating code coverage report"
+            )
+            
+            # Add coverage clean target
+            add_custom_target(coverage-clean
+                COMMAND ${CMAKE_COMMAND} -E remove_directory coverage_html
+                COMMAND ${CMAKE_COMMAND} -E remove coverage.info
+                COMMAND ${LCOV_PATH} --directory . --zerocounters
+                WORKING_DIRECTORY ${CMAKE_BINARY_DIR}
+                COMMENT "Cleaning coverage data"
+            )
+        endif()
+    else()
+        message(WARNING "Code coverage is only supported with GCC or Clang compilers")
+    endif()
+endif()
 if(MSCCLPP_GPU_ARCHS)
     string(STRIP "${MSCCLPP_GPU_ARCHS}" MSCCLPP_GPU_ARCHS)
     string(REPLACE " " ";" MSCCLPP_GPU_ARCHS "${MSCCLPP_GPU_ARCHS}")

test/CMakeLists.txt

@@ -7,7 +7,6 @@ set(TEST_LIBS_COMMON mscclpp ${GPU_LIBRARIES} ${NUMA_LIBRARIES} Threads::Threads
 if(MSCCLPP_USE_IB)
     list(APPEND TEST_LIBS_COMMON ${IBVERBS_LIBRARIES})
 endif()
-set(TEST_LIBS_GTEST GTest::gtest_main GTest::gmock_main)
 set(TEST_INC_COMMON PRIVATE ${PROJECT_SOURCE_DIR}/include SYSTEM PRIVATE ${GPU_INCLUDE_DIRS})
 set(TEST_INC_INTERNAL PRIVATE ${PROJECT_SOURCE_DIR}/src/core/include)
 
@@ -38,25 +37,25 @@ add_test_executable(executor_test executor_test.cc)
 configure_file(run_mpi_test.sh.in run_mpi_test.sh)
 
 include(CTest)
-include(FetchContent)
-FetchContent_Declare(googletest URL https://github.com/google/googletest/archive/refs/tags/v1.14.0.zip)
-option(INSTALL_GTEST OFF)
-FetchContent_MakeAvailable(googletest)
-include(GoogleTest)
+
+# Build test framework library
+add_library(test_framework STATIC framework.cc)
+target_include_directories(test_framework PUBLIC ${CMAKE_CURRENT_SOURCE_DIR})
+target_link_libraries(test_framework PUBLIC MPI::MPI_CXX)
 
 # Unit tests
 add_executable(unit_tests)
-target_link_libraries(unit_tests ${TEST_LIBS_COMMON} ${TEST_LIBS_GTEST})
+target_link_libraries(unit_tests ${TEST_LIBS_COMMON} test_framework)
 target_include_directories(unit_tests ${TEST_INC_COMMON} ${TEST_INC_INTERNAL})
 add_subdirectory(unit)
-gtest_discover_tests(unit_tests DISCOVERY_MODE PRE_TEST)
+add_test(NAME unit_tests COMMAND unit_tests)
 
 # Multi-process unit tests
 add_executable(mp_unit_tests)
-target_link_libraries(mp_unit_tests ${TEST_LIBS_COMMON} ${TEST_LIBS_GTEST} MPI::MPI_CXX)
+target_link_libraries(mp_unit_tests ${TEST_LIBS_COMMON} test_framework MPI::MPI_CXX)
 target_include_directories(mp_unit_tests ${TEST_INC_COMMON} ${TEST_INC_INTERNAL})
 add_subdirectory(mp_unit)
-gtest_discover_tests(mp_unit_tests DISCOVERY_MODE PRE_TEST)
+add_test(NAME mp_unit_tests COMMAND ${CMAKE_CURRENT_BINARY_DIR}/run_mpi_test.sh mp_unit_tests 2)
 
 # mscclpp-test
 add_subdirectory(mscclpp-test)

test/perf/CMakeLists.txt

@@ -22,7 +22,7 @@ function(add_perf_test_executable name sources)
         set_source_files_properties(${sources} PROPERTIES LANGUAGE CXX)
     endif()
     add_executable(${name} ${sources})
-    target_link_libraries(${name} ${PERF_TEST_LIBS_COMMON})
+    target_link_libraries(${name} ${PERF_TEST_LIBS_COMMON} test_framework)
 
     # Link nlohmann_json - use the target from main project
     target_link_libraries(${name} nlohmann_json::nlohmann_json)