CMake + Qt + GTest files linking - c++

Question

I have a simple CMake + Qt + GTest project:
.
├── CMakeLists.txt
├── src
│   ├── CMakeLists.txt
│   ├── main.cpp
│   └── utils
│   ├── calculator.cpp
│   └── calculator.h
└── tests
├── calculator_test.cpp
└── CMakeLists.txt
Root CMakeFiles.txt
cmake_minimum_required(VERSION 3.5)
project(random_project)
# Place binaries and libraries according to GNU standards.
include(GNUInstallDirs)
set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/${CMAKE_INSTALL_LIBDIR})
set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/${CMAKE_INSTALL_LIBDIR})
set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/${CMAKE_INSTALL_BINDIR})
# Add source folder.
add_subdirectory(src)
# Add GTest.
include(cmake/googletest.cmake)
fetch_googletest(
${PROJECT_SOURCE_DIR}/cmake
${PROJECT_BINARY_DIR}/googletest
)
enable_testing()
# Add tests folder.
add_subdirectory(tests)
And I want to reach calculator.h in calculator_test.cpp which uses GTest:
#include <gtest/gtest.h>
#include "utils/calculator.h" // <- Want to reach this in that path format.
TEST(example, add)
{
EXPECT_EQ(8, Calculator::sum(3, 5));
}
I have tried to link but then test is not found and the path is releative:
tests/CMakeFiles.txt
# Find the Qt libraries.
find_package(Qt5Widgets REQUIRED)
# Qt5 libraries.
set(QT5_LIBRARIES
Qt5::Widgets)
# Source files.
set(SOURCE_FILES
calculator_test.cpp
../src/utils/calculator.cpp
../src/utils/calculator.h
../src/main.cpp) # If I link like this, test is not found.
# Tell CMake to create the executable.
add_executable(unit_tests ${SOURCE_FILES})
# Use the Widgets module from Qt5.
target_link_libraries(unit_tests ${QT5_LIBRARIES} gtest_main)
# Add tests.
add_test(
NAME unit_tests
COMMAND ${CMAKE_BINARY_DIR}/${CMAKE_INSTALL_BINDIR}/unit_tests
)
How to link calculator.h in calculator_test.cpp test with CMakeLists.txt?

Answer 1

My Qt project with CMake project file cannot resolve the path to
"someHeader.h". What can I do to fix it?
You can specify the include path:
include_directories("${PROJECT_SOURCE_DIR}/relativePathToHeader")
and likely the path needed:
include_directories("${PROJECT_SOURCE_DIR}/src/utils") or maybe
include_directories("${PROJECT_SOURCE_DIR}/utils") depending on where the source directory actually is.
You need to re-run CMake, of course.