TempDir: Simplified Temporary Directory for C++

TempDir is a lightweight C++17 library designed to provide an easy-to-use solution for managing temporary directories and files, particularly in unit testing scenarios (e.g., with Catch2). Inspired by JUnit's @TempDir annoation in the Java ecosystem, TempDir simplifies the creation, cleanup, and management of temporary directories in your C++ projects.

The library is implemented as a single-header file, making integration easy and comes without additional dependencies. The project is licensed under the MIT License.

Features

• Automatic cleanup: Configurable cleanup policies to manage temporary directories' lifecycle.
• Easy integration: A single-header implementation that can be directly included in your project.
• Unit test focus: Perfect for use in testing frameworks like Catch2
• Modern C++ support: Written in C++17 for robust and efficient performance.

Installation

Simply copy the tempdir.hpp file into your project and include it in your source files:

#include <bw/tempdir/tempdir.hpp>

You can also use the vcpkg port bw-tempdir

vcpkg install bw-tempdir

or add dependency to vpkg.json manifest file

{
  "name": "your-project",
  "version-string": "1.0.0",
  "dependencies": [
    "bw-tempdir",
    ...
  ]
}

Example Usage

Creating and Managing a Temporary Directory

#include <bw/tempdir/tempdir.hpp>
#include <filesystem>
#include <fstream>
#include <iostream>

using namespace bw::tempdir;

int main()
{
    try
    {
        TempDir temp_dir; // Creates a temporary directory in the system's temp folder.

        // Access the directory path
        std::cout << "Temporary directory created at: " << temp_dir.path() << std::endl;

        // Perform operations in the temp directory
        auto test_file = temp_dir.path() / "example.txt";
        std::ofstream(test_file) << "Hello, TempDir!";

        std::cout << "Created file: " << test_file << std::endl;

        // Directory is automatically cleaned up based on the cleanup policy
        // when temp_dir goes out of scope.
    }
    catch (const TempDirException& ex)
    {
        std::cerr << "An error occurred: " << ex.what() << std::endl;
    }

    return 0;
}

Please do also check examples directory for more examples.

Using TempDir in Catch2 Unit Tests

#include <bw/tempdir/tempdir.hpp>
#include <catch2/catch_all.hpp>
#include <filesystem>
#include <fstream>

using namespace bw::tempdir;
namespace fs = std::filesystem;

TEST_CASE("TempDir usage in unit tests")
{
    TempDir temp_dir;

    REQUIRE(fs::exists(temp_dir.path())); // Temp directory should exist.

    auto test_file = temp_dir.path() / "test.txt";
    std::ofstream(test_file) << "Unit test data";

    REQUIRE(fs::exists(test_file)); // File should be created.
}
// temp_dir out of scope, created temp directory will be removed

Cleanup Policies

The TempDir class offers configurable cleanup policies:

• Cleanup::always: Always clean up the directory when TempDir goes out of scope.
• Cleanup::on_success: Clean up only if no exceptions were thrown.
• Cleanup::never: Keep the directory and its contents.

You can set the cleanup policy in the constructor:

TempDir temp_dir(Cleanup::on_success);

Logging

Disabled by default TempDir supports customizable logging by allowing you to provide a logging function in the Config object:

// print to std::cout
TempDir temp_dir(Config().enable_logging());

// TempDir create '/tmp/temp_dir_1732162084442_37189'
// TempDir remove '/tmp/temp_dir_1732162084442_37189'


// forward to custom logger
TempDir temp_dir(Config().enable_logging([](auto& msg) { 
    spdlog::info(msg);
}));

License

TempDir is licensed under the MIT License. See LICENSE for details.

Contributing

Contributions are welcome! If you encounter a bug, have a feature request, or would like to contribute code, feel free to open an issue or submit a pull request.