如何通过单元测试（使用 CMake 和 GTest）知道测试数据的文件夹在哪里？

Question

I am using CMake and GTest to unit test a C++ program. One of my tests uses fopen() to open a file of test data.

I am struggling to figure out how to not get a "No such file or directory" error.

Directory Structure

├── CMakeLists.txt
├── build
├── src
│   └── myProgram.cxx
└── tests
    ├── CMakeLists.txt
    ├── data
    │   ├── dataset1.txt
    │   ├── dataset2.txt
    │   ├── dataset3.txt
    │   └── dataset4.txt
    └── myProgramTests.cxx

Test Code

TEST(test, read_data_file) {
    // Open test file
    std::FILE *f = fopen("inputs/dataset1.txt", "r");
    if (f == NULL){
        perror ("Error opening file");
    }
    fclose(f);
}

This seems simple, but I can't figure out what to put here. I have tried "dataset1.txt" , "inputs/dataset1.txt" , "tests/inputs/dataset1.txt" . What am I missing / is there a way for me into "include" these files via a line in CMakeLists.txt so I can just read them in with one of the strings I tried above?

Summary : How do I properly reference the location of files stored in a tests/data subdirectory within GTest?

Answer 1

Use ctest of cmake. Its add_test command has a useful property WORKING_DIRECTORY that are you looking for.

Answer 2

Paths that do not start with a / are relative to your current working directory, ie the directory your shell is in when you run the tests.

For example, if your current working directory is the top-level directory of your project, then the relative path to dataset1.txt is tests/data/dataset1.txt