C unit testing with multiple test files

[student868]

Hi,

I am trying to use multiple test files for C code.
I include the same headers on both files inside extern block but keep getting LNK2005 error (on one file I include also the .c files because it won't compile otherwise).

can someone have an idea why? (I do have guards inside the header files).

Thanks

[joshiayush]

Linker Tools Error LNK2005

This error can occur when a header file defines a function that isn't inline . If you include this header file in more than one source file, you get multiple definitions of the function in the executable.

Or in general if you define your functions in header files and include them in multiple object files then you're gonna get this error anyways.

Could you please post the code that is creating that error?

[student868]

hi,

thanks for your reply. I have the following files:

try.h

#ifndef TRY_TRY_H
#define TRY_TRY_H

#include <stdio.h>

int hello_world();

#endif //TRY_TRY_H

try.c

#include "try.h"

int hello_world(){
    printf("hello world!\n");
    return 0;
}

tests.cpp

#include <fstream>
#include "gtest/gtest.h"

extern "C" {
#include "../../try.h"
#include "../../try.c"
}

TEST(t1, t1a) {
    EXPECT_EQ(hello_world(), 0);
}

tests2.cpp

#include <fstream>
#include "gtest/gtest.h"

extern "C" {
#include "../../try.h"
#include "../../try.c"
}

TEST(t2, t2a) {
    EXPECT_EQ(hello_world(), 0);
}

CMakeLists.txt:

project(Google_tests)

add_subdirectory(lib)
include_directories(${gtest_SOURCE_DIR}/include ${gtest_SOURCE_DIR})

add_executable(Google_Tests_run tests/tests.cpp tests/tests2.cpp)

target_link_libraries(Google_Tests_run gtest gtest_main)

How can I use ".c" & ".h" files in multiple test files with google test?

thanks

[ghost]

@student868

I think it seems also good to have multiple executables(test binaries) rather than having just one executable
And then you can run all of them at once with the command ctest (or make test or ninja test) on shell

enable_testing()

function(create_test name)
  add_executable(${name} tests/${name}.cpp)
  target_link_libraries(${name} gtest gtest_main)
  add_test(NAME ${name} COMMAND "$<TARGET_FILE:${name}>")
endfunction()

create_test(tests)    # for tests/tests.cpp
create_test(tests2)   # for tests/tests2.cpp

Another practice can be found here : https://cliutils.gitlab.io/modern-cmake/chapters/testing/googletest.html