Allow project to be used as a library

See cpm-cmake/CPM.cmake#275 (comment)

Author: flaviut

CMakeLists.txt

@@ -8,27 +8,32 @@ add_library(fpm INTERFACE)
 
 target_include_directories(fpm INTERFACE include)
 
+# if this project is being used as a submodule, it's someone elses' dependency.
+# in that case, we don't want to set up any testing, since they just want to
+# use it as a library.
+get_directory_property(hasParent PARENT_DIRECTORY)
+if(NOT hasParent)
 #
 # Test suite
 #
 enable_testing()
 include(GoogleTest)
 
 add_executable(fpm-test
-  tests/arithmetic.cpp
-  tests/arithmetic_int.cpp
-  tests/basic_math.cpp
-  tests/constants.cpp
-  tests/conversion.cpp
-  tests/classification.cpp
-  tests/customizations.cpp
-  tests/detail.cpp
-  tests/input.cpp
-  tests/manip.cpp
-  tests/nearest.cpp
-  tests/output.cpp
-  tests/power.cpp
-  tests/trigonometry.cpp
+tests/arithmetic.cpp
+tests/arithmetic_int.cpp
+tests/basic_math.cpp
+tests/constants.cpp
+tests/conversion.cpp
+tests/classification.cpp
+tests/customizations.cpp
+tests/detail.cpp
+tests/input.cpp
+tests/manip.cpp
+tests/nearest.cpp
+tests/output.cpp
+tests/power.cpp
+tests/trigonometry.cpp
 )
 set_target_properties(fpm-test PROPERTIES CXX_STANDARD 11)
 target_link_libraries(fpm-test PRIVATE fpm gtest_main)
@@ -44,29 +49,29 @@ include(ExternalProject)
 set(LIBFIXMATH_ROOT "${CMAKE_CURRENT_BINARY_DIR}/libfixmath")
 
 ExternalProject_Add(libfixmath-external
-  GIT_REPOSITORY "https://github.com/PetteriAimonen/libfixmath.git"
-  GIT_TAG bada934981a5961569ad2cb6b9006ed94542cc9c
-  PREFIX ${LIBFIXMATH_ROOT}
-  CONFIGURE_COMMAND ""
-  BUILD_COMMAND ""
-  INSTALL_COMMAND ""
+GIT_REPOSITORY "https://github.com/PetteriAimonen/libfixmath.git"
+GIT_TAG bada934981a5961569ad2cb6b9006ed94542cc9c
+PREFIX ${LIBFIXMATH_ROOT}
+CONFIGURE_COMMAND ""
+BUILD_COMMAND ""
+INSTALL_COMMAND ""
 )
 
 set(LIBFIXMATH_SOURCES
-  ${LIBFIXMATH_ROOT}/src/libfixmath-external/libfixmath/fix16.c
-  ${LIBFIXMATH_ROOT}/src/libfixmath-external/libfixmath/fix16_exp.c
-  ${LIBFIXMATH_ROOT}/src/libfixmath-external/libfixmath/fix16_sqrt.c
-  ${LIBFIXMATH_ROOT}/src/libfixmath-external/libfixmath/fix16_str.c
-  ${LIBFIXMATH_ROOT}/src/libfixmath-external/libfixmath/fix16_trig.c
-  ${LIBFIXMATH_ROOT}/src/libfixmath-external/libfixmath/fract32.c
-  ${LIBFIXMATH_ROOT}/src/libfixmath-external/libfixmath/uint32.c
+${LIBFIXMATH_ROOT}/src/libfixmath-external/libfixmath/fix16.c
+${LIBFIXMATH_ROOT}/src/libfixmath-external/libfixmath/fix16_exp.c
+${LIBFIXMATH_ROOT}/src/libfixmath-external/libfixmath/fix16_sqrt.c
+${LIBFIXMATH_ROOT}/src/libfixmath-external/libfixmath/fix16_str.c
+${LIBFIXMATH_ROOT}/src/libfixmath-external/libfixmath/fix16_trig.c
+${LIBFIXMATH_ROOT}/src/libfixmath-external/libfixmath/fract32.c
+${LIBFIXMATH_ROOT}/src/libfixmath-external/libfixmath/uint32.c
 )
 set_source_files_properties(${LIBFIXMATH_SOURCES} PROPERTIES GENERATED TRUE)
 add_library(libfixmath ${LIBFIXMATH_SOURCES})
 
 # Set libfixmath compile options to match fpm functionality
 target_compile_definitions(libfixmath
-  PUBLIC
+PUBLIC
     FIXMATH_NO_CACHE        # No caching of results
 
     #FIXMATH_NO_OVERFLOW    # We want no runtime-overflow detection, but it fails to compile
@@ -86,12 +91,12 @@ add_dependencies(libfixmath libfixmath-external)
 set(LIBCNL_ROOT "${CMAKE_CURRENT_BINARY_DIR}/libcnl")
 
 ExternalProject_Add(libcnl-external
-  GIT_REPOSITORY "https://github.com/johnmcfarlane/cnl"
-  GIT_TAG 4d445566fe7c6c8939fffc145a2f30fd587796a6
-  PREFIX ${LIBCNL_ROOT}
-  CONFIGURE_COMMAND ""
-  BUILD_COMMAND ""
-  INSTALL_COMMAND ""
+GIT_REPOSITORY "https://github.com/johnmcfarlane/cnl"
+GIT_TAG 4d445566fe7c6c8939fffc145a2f30fd587796a6
+PREFIX ${LIBCNL_ROOT}
+CONFIGURE_COMMAND ""
+BUILD_COMMAND ""
+INSTALL_COMMAND ""
 )
 
 add_library(libcnl INTERFACE)
@@ -103,9 +108,9 @@ add_dependencies(libcnl libcnl-external)
 # Runs benchmarks of FPM operations and dumps results to standard output.
 #
 add_executable(fpm-benchmark
-	benchmarks/arithmetic.cpp
-	benchmarks/power.cpp
-	benchmarks/trigonometry.cpp
+    benchmarks/arithmetic.cpp
+    benchmarks/power.cpp
+    benchmarks/trigonometry.cpp
 )
 target_link_libraries(fpm-benchmark PRIVATE fpm libfixmath libcnl benchmark benchmark_main)
 
@@ -114,20 +119,20 @@ target_link_libraries(fpm-benchmark PRIVATE fpm libfixmath libcnl benchmark benc
 # Dumps the accuracy of approximated FPM functions to JSON files.
 #
 add_executable(fpm-accuracy
-	accuracy/accuracy.cpp
+    accuracy/accuracy.cpp
 )
 set_target_properties(fpm-accuracy PROPERTIES CXX_STANDARD 14)
 target_link_libraries(fpm-accuracy PRIVATE fpm libfixmath)
 
 
 include(FindGnuplot)
 if (GNUPLOT_FOUND)
-  # Create accuracy data
-  set(DATA_DIR ${CMAKE_CURRENT_BINARY_DIR})
+# Create accuracy data
+set(DATA_DIR ${CMAKE_CURRENT_BINARY_DIR})
 
-  set(DATA_FILES_ACCURACY "")
-  set(IMG_FILES_ACCURACY "")
-  foreach(DATA sin-trig cos-trig tan-trig asin-invtrig acos-invtrig atan-invtrig atan2-trig sqrt-auto cbrt-auto pow-auto exp-auto exp2-auto log-auto log2-auto log10-auto)
+set(DATA_FILES_ACCURACY "")
+set(IMG_FILES_ACCURACY "")
+foreach(DATA sin-trig cos-trig tan-trig asin-invtrig acos-invtrig atan-invtrig atan2-trig sqrt-auto cbrt-auto pow-auto exp-auto exp2-auto log-auto log2-auto log10-auto)
     string(REGEX MATCHALL "[^-]+" M ${DATA})
     list(GET M 0 SERIES)
     list(GET M 1 TYPE)
@@ -137,62 +142,63 @@ if (GNUPLOT_FOUND)
     list(APPEND IMG_FILES_ACCURACY ${IMG_FILE})
 
     add_custom_command(
-      OUTPUT ${IMG_FILE}
-      COMMAND ${GNUPLOT_EXECUTABLE} -c ${PROJECT_SOURCE_DIR}/accuracy/accuracy.gnuplot ${SERIES} ${TYPE}
-      DEPENDS ${DATA_DIR}/${SERIES}.csv accuracy/accuracy.gnuplot
-      WORKING_DIRECTORY ${DATA_DIR}
-      VERBATIM
-      COMMENT "Plotting ${SERIES} accuracy data"
+    OUTPUT ${IMG_FILE}
+    COMMAND ${GNUPLOT_EXECUTABLE} -c ${PROJECT_SOURCE_DIR}/accuracy/accuracy.gnuplot ${SERIES} ${TYPE}
+    DEPENDS ${DATA_DIR}/${SERIES}.csv accuracy/accuracy.gnuplot
+    WORKING_DIRECTORY ${DATA_DIR}
+    VERBATIM
+    COMMENT "Plotting ${SERIES} accuracy data"
     )
-  endforeach(DATA)
+endforeach(DATA)
 
-  add_custom_command(
+add_custom_command(
     OUTPUT ${DATA_FILES_ACCURACY}
     COMMAND fpm-accuracy
     DEPENDS fpm-accuracy
     WORKING_DIRECTORY ${DATA_DIR}
     VERBATIM
     COMMENT "Generating accuracy data with fpm-accuracy"
-  )
+)
 
-  add_custom_target(fpm-accuracy-images DEPENDS ${IMG_FILES_ACCURACY})
+add_custom_target(fpm-accuracy-images DEPENDS ${IMG_FILES_ACCURACY})
 endif()
 
 if (CMAKE_BUILD_TYPE STREQUAL "Release")
-  # Enable the performance data-generation command only for Release builds.
+# Enable the performance data-generation command only for Release builds.
 
-  set(DATA_FILE_PERFORMANCE_JSON ${DATA_DIR}/performance.json)
-  add_custom_command(
+set(DATA_FILE_PERFORMANCE_JSON ${DATA_DIR}/performance.json)
+add_custom_command(
     OUTPUT ${DATA_FILE_PERFORMANCE_JSON}
     COMMAND fpm-benchmark --benchmark_out=${DATA_FILE_PERFORMANCE_JSON} --benchmark_out_format=json
     DEPENDS fpm-benchmark
     WORKING_DIRECTORY ${DATA_DIR}
     VERBATIM
     COMMENT "Generating performance data with fpm-benchmark"
-  )
+)
 
-  set(DATA_FILE_PERFORMANCE_GNUPLOT ${DATA_DIR}/performance.csv)
-  add_custom_command(
+set(DATA_FILE_PERFORMANCE_GNUPLOT ${DATA_DIR}/performance.csv)
+add_custom_command(
     OUTPUT ${DATA_FILE_PERFORMANCE_GNUPLOT}
     COMMAND python ${PROJECT_SOURCE_DIR}/benchmarks/benchmark.py ${DATA_FILE_PERFORMANCE_JSON} ${DATA_FILE_PERFORMANCE_GNUPLOT}
     DEPENDS ${DATA_FILE_PERFORMANCE_JSON} ${PROJECT_SOURCE_DIR}/benchmarks/benchmark.py
     WORKING_DIRECTORY ${DATA_DIR}
     VERBATIM
     COMMENT "Converting performance data for GnuPlot"
-  )
+)
 
-  set(IMG_FILE_PERFORMANCE "{$DATA_DIR}/performance.png")
-  add_custom_command(
+set(IMG_FILE_PERFORMANCE "{$DATA_DIR}/performance.png")
+add_custom_command(
     OUTPUT ${IMG_FILE_PERFORMANCE}
     COMMAND ${GNUPLOT_EXECUTABLE} ${PROJECT_SOURCE_DIR}/benchmarks/benchmark.gnuplot
     DEPENDS ${DATA_FILE_PERFORMANCE_GNUPLOT} ${PROJECT_SOURCE_DIR}/benchmarks/benchmark.gnuplot
     WORKING_DIRECTORY ${DATA_DIR}
     VERBATIM
     COMMENT "Plotting performance data"
-  )
+)
 
-  add_custom_target(fpm-performance-images DEPENDS ${IMG_FILE_PERFORMANCE})
+add_custom_target(fpm-performance-images DEPENDS ${IMG_FILE_PERFORMANCE})
 endif()
 
 add_subdirectory(3rdparty/googlebench)
 add_subdirectory(3rdparty/googletest)
+endif()