[Script] Add a tool to test the code coverage. (#325)

This PR adds a script to test the code coverage.

---------

Co-authored-by: Yixin Dong <[email protected]>

Author: Seven-Streams

CMakeLists.txt

@@ -19,6 +19,7 @@ option(XGRAMMAR_BUILD_CXX_TESTS "Build C++ tests" OFF)
 option(XGRAMMAR_ENABLE_CPPTRACE
        "Enable C++ trace (Now only support Linux, and RelWithDebugInfo or Debug build)" OFF
 )
+option(XGRAMMAR_ENABLE_COVERAGE "Enable code coverage with gcov" OFF)
 
 set(XGRAMMAR_CUDA_ARCHITECTURES
     native
@@ -93,3 +94,16 @@ if(XGRAMMAR_BUILD_CXX_TESTS)
   include(GoogleTest)
   gtest_discover_tests(xgrammar_test)
 endif()
+
+if(XGRAMMAR_ENABLE_COVERAGE)
+  target_link_libraries(xgrammar_bindings PRIVATE gcov)
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fprofile-arcs -ftest-coverage")
+  set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fprofile-arcs -ftest-coverage")
+
+  set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} --coverage")
+  set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} --coverage")
+
+  if(XGRAMMAR_BUILD_PYTHON_BINDINGS)
+    set(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS} --coverage")
+  endif()
+endif()

cmake/config.cmake

@@ -1,4 +1,5 @@
 set(CMAKE_BUILD_TYPE RelWithDebInfo)
 set(XGRAMMAR_BUILD_PYTHON_BINDINGS ON)
+set(XGRAMMAR_ENABLE_COVERAGE OFF)
 set(XGRAMMAR_BUILD_CXX_TESTS OFF)
 set(XGRAMMAR_ENABLE_CPPTRACE OFF)

docs/how_to/code_coverage.rst

@@ -0,0 +1,18 @@
+.. _how-to-test-code-coverage:
+
+Code Coverage Test
+==================
+
+The script ``run_coverage.sh`` offers a way to test the code coverage
+of the XGrammar library.
+
+To run the coverage test, please follow these steps:
+
+#. In ``config.cmake``, set the variable ``XGRAMMAR_ENABLE_COVERAGE`` to ``ON``.
+#. Compile the XGrammar library with the configured settings.
+#. Run the script ``run_coverage.sh`` in the root directory of the XGrammar library.
+
+After running the script, you will find the coverage report in the
+``coverage_report`` directory.
+
+You can modify the script to change the test cases or the output directory.

scripts/run_coverage.sh

@@ -0,0 +1,11 @@
+#!/bin/bash
+
+# Usage: bash ./scripts/run_coverage.sh
+lcov --directory . --zerocounters
+ctest --test-dir build -V --timeout 60 --stop-on-failure
+pytest
+
+lcov --gcov-tool /usr/bin/gcov-13 --directory . --capture --output-file coverage.info --ignore-errors mismatch,gcov
+genhtml coverage.info --output-directory coverage_report --ignore-errors version
+rm coverage.info
+echo "Coverage report generated at: $(pwd)/coverage_report/index.html"