Creating c++ library using cmake - c++

Question

Dear cmake / c++ experts,
I created a small library for display and input on the console. Now I would like to use it in another project. Unfortunately, even after quite some time spent in the cmake documents, I cannot get it to work.
The library is here: https://github.com/HEIGVD-PRG1-F-2022/prg1f-io and uses the following CMakeLists.txt:
cmake_minimum_required(VERSION 3.23)
project(prg1f-io VERSION 0.1 DESCRIPTION "Input and display methods for PRG1-F")
set(CMAKE_CXX_STANDARD 20)
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall")
add_library(prg1f-io STATIC src/display.cpp)
set_target_properties(prg1f-io PROPERTIES VERSION ${PROJECT_VERSION})
set_target_properties(prg1f-io PROPERTIES PUBLIC_HEADER include/display.h)
include(GNUInstallDirs)
install(TARGETS prg1f-io
LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
PUBLIC_HEADER DESTINATION ${CMAKE_INSTALL_INCLUDEDIR})
And I created a small test here: https://github.com/HEIGVD-PRG1-F-2022/prg1f-test with the following CMakeLists.txt:
cmake_minimum_required(VERSION 3.23)
project(prg1f_test)
set(CMAKE_CXX_STANDARD 20)
include(FetchContent)
FetchContent_Declare(prg1f-io
GIT_REPOSITORY https://github.com/HEIGVD-PRG1-F-2022/prg1f-io.git
GIT_TAG main
)
FetchContent_MakeAvailable(prg1f-io)
add_executable(prg1f-test main.cpp)
target_link_libraries(prg1f-test PRIVATE prg1f-io)
While the CMakeLists.txt in the test does download the library and compiles it, I cannot get access to the header files in the test. I tried different includes, but none of the following work:
#include <prg1f-io/include/display.h>
#include <prg1f-io/display.h>
#include <prg1f-io>
#include <display.h>
I'm sure it's a little line somewhere in one of the CMakeLists.txt, but I cannot find it.
Any help is greatly appreciated!

Answer 1

Thanks to #Tsyvarev, I can now rest in peace:
The CMakeLists.txt of the library:
cmake_minimum_required(VERSION 3.23)
project(prg1f-io VERSION 0.1 DESCRIPTION "Input and display methods for PRG1-F")
set(CMAKE_CXX_STANDARD 20)
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall")
add_library(prg1f-io STATIC src/display.cpp)
set_target_properties(prg1f-io PROPERTIES VERSION ${PROJECT_VERSION})
target_include_directories(prg1f-io PUBLIC include)
And the CMakeLists.txt of the binary using the library:
cmake_minimum_required(VERSION 3.23)
project(prg1f_test)
set(CMAKE_CXX_STANDARD 20)
include(FetchContent)
FetchContent_Declare(prg1f-io
GIT_REPOSITORY https://github.com/HEIGVD-PRG1-F-2022/prg1f-io.git
GIT_TAG main
)
FetchContent_MakeAvailable(prg1f-io)
add_executable(prg1f-test main.cpp)
target_link_libraries(prg1f-test PRIVATE prg1f-io)
Now I can include the headers using:
#include <display.h>
All I'm missing now is how to #include<prg1f-io/display.h> without having to add a prg1f-io/include/prg1f-io/display.h directory.