Merge branch 'add-coverage'

4 files changed, 87 insertions, 4 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index a8240a2..621136c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -9,10 +9,6 @@ endif()
 
 find_package(SFML 2 REQUIRED COMPONENTS graphics)
 
-configure_file(config.h.in config.h ESCAPE_QUOTES @ONLY)
-include_directories("${CMAKE_CURRENT_BINARY_DIR}"
-  "${CMAKE_CURRENT_SOURCE_DIR}/include")
-
 # Add debugging warnings.
 if(MSVC)
   string(APPEND CMAKE_CXX_FLAGS_DEBUG " /W4")
@@ -22,6 +18,17 @@ else()
   CACHE STRING "Flags used by the CXX compiler during DEBUG builds.")
 endif()
 
+set(CMAKE_BUILD_TYPE "${CMAKE_BUILD_TYPE}" CACHE STRING
+  "Choose the type of build: None, Debug, Release, RelWithDebInfo, \
+MinSizeRel, or Coverage")
+list(APPEND CMAKE_CONFIGURATION_TYPES Coverage)
+
+include(cmake/Coverage.cmake)
+
+configure_file(config.h.in config.h ESCAPE_QUOTES @ONLY)
+include_directories("${CMAKE_CURRENT_BINARY_DIR}"
+  "${CMAKE_CURRENT_SOURCE_DIR}/include")
+
 add_subdirectory(src)
 
 if("${BUILD_TESTING}" OR "${STARS_BUILD_TESTING}")
diff --git a/README.md b/README.md
index ba4588a..6b0f350 100644
--- a/README.md
+++ b/README.md
@@ -15,6 +15,14 @@ sh config.sh
 cmake --build build
 ```
 
+## Developer instructions
+
+### Coverage
+To generate coverage reports, build the project with
+`-DCMAKE_BUILD_TYPE=Coverage`, then from the `build/` directory, execute
+`src/main`. Perform actions, exit cleanly, then run `make coverage`. Coverage
+reporting is supported on Apple (LLVM) and Linux (gcov/lcov).
+
 ## Bug reports, questions, etc.
 
 * The stars homepage is hosted at <https://git.aidenw.net/stars/about/>
diff --git a/cmake/Coverage.cmake b/cmake/Coverage.cmake
new file mode 100644
index 0000000..5d2e2e0
--- /dev/null
+++ b/cmake/Coverage.cmake
@@ -0,0 +1,66 @@
+string(TOLOWER "${CMAKE_BUILD_TYPE}" build_type)
+
+if(CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
+set(CMAKE_CXX_FLAGS_COVERAGE
+        "-g -O0 -fprofile-instr-generate -fcoverage-mapping" CACHE STRING
+        "Flags used by the CXX compiler during COVERAGE builds."
+        FORCE)
+set(CMAKE_EXE_LINKER_FLAGS_COVERAGE "-fprofile-instr-generate" CACHE STRING
+        "Flags used by the linker during COVERAGE builds." FORCE)
+find_program(LLVM-PROFDATA llvm-profdata)
+find_program(LLVM-COV llvm-cov)
+elseif(CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
+find_program(LCOV lcov)
+find_program(GENHTML genhtml)
+set(CMAKE_CXX_FLAGS_COVERAGE "-g -O0 --coverage -fkeep-inline-functions \
+-fkeep-static-functions" CACHE STRING
+  "Flags used by the CXX compiler during COVERAGE builds." FORCE)
+set(CMAKE_EXE_LINKER_FLAGS_COVERAGE "--coverage" CACHE STRING
+  "Flags used by the linker during COVERAGE builds." FORCE)
+endif()
+mark_as_advanced(CMAKE_CXX_FLAGS_COVERAGE CMAKE_EXE_LINKER_FLAGS_COVERAGE)
+
+if(build_type STREQUAL "coverage")
+set(STARS_COVERAGE_DIR "${CMAKE_CURRENT_BINARY_DIR}/coverage" CACHE STRING
+  "Coverage HTML output directory for stars.")
+
+# Meta-target for subdirectory coverage.
+add_custom_target(coverage
+  # build/coverage/ is usually created by dependents but needed for BYPRODUCTS.
+  "${CMAKE}" -E make_directory "${STARS_COVERAGE_DIR}"
+  BYPRODUCTS "${STARS_COVERAGE_DIR}")
+endif()
+
+# Make a coverage report in the subdirectory SUBDIR with coverage from targets
+# OBJ1...ARGN. Does nothing if this is not a "Coverage" build.
+function(cover_subdirectory_targets SUBDIR OBJ1)
+if(build_type STREQUAL "coverage")
+if(CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
+set(LLVM_COV_OBJECTS -object "$<TARGET_FILE:${OBJ1}>")
+foreach(tgt ${ARGN})
+string(APPEND LLVM_COV_OBJECTS -object "$<TARGET_FILE:${tgt}>")
+endforeach()
+
+add_custom_target(coverage-${SUBDIR}
+  "${LLVM-PROFDATA}" merge -o "${CMAKE_CURRENT_BINARY_DIR}/${SUBDIR}.profdata"
+  -sparse "${PROJECT_BINARY_DIR}/default.profraw"
+  COMMAND "${LLVM-COV}" show ${LLVM_COV_OBJECTS}
+  -instr-profile="${CMAKE_CURRENT_BINARY_DIR}/${SUBDIR}.profdata"
+  -output-dir="${STARS_COVERAGE_DIR}/${SUBDIR}" -format=html
+  COMMENT "Coverage available at file://${STARS_COVERAGE_DIR}/${SUBDIR}"
+  BYPRODUCTS "${STARS_COVERAGE_DIR}/${SUBDIR}")
+add_dependencies(coverage coverage-${SUBDIR})
+elseif(CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
+add_custom_target(coverage-${SUBDIR}
+  "${LCOV}" -q --demangle-cpp --capture --no-external
+  --base-directory "${PROJECT_SOURCE_DIR}"
+  --directory "${CMAKE_CURRENT_BINARY_DIR}"
+  -o "${CMAKE_CURRENT_BINARY_DIR}/coverage.info"
+  COMMAND "${GENHTML}" -q -o "${STARS_COVERAGE_DIR}/${SUBDIR}"
+  "${CMAKE_CURRENT_BINARY_DIR}/coverage.info"
+  COMMENT "Coverage available at file://${STARS_COVERAGE_DIR}/${SUBDIR}"
+  BYPRODUCTS "${STARS_COVERAGE_DIR}/${SUBDIR}")
+add_dependencies(coverage coverage-${SUBDIR})
+endif()
+endif()
+endfunction()
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 31a39ad..5590923 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -23,3 +23,5 @@ target_link_libraries(main app)
 
 # Only installation target is this exe.
 install(TARGETS main DESTINATION bin)
+
+cover_subdirectory_targets(src main)