SimpleTest: Simple unit testing for C++

by Reece Jones

Overview

SimpleTest is designed to be an easy-to-use framework for basic unit testing tasks.
Ever wanted to smash out a few quick unit tests, but don't want the extensive - but harder to use - features of, say, GoogleTest? Then SimpleTest may be the framework for you!

Features

• Very simple to use
• Basic boolean & exception assertions
• Automatic main() generation
• Concise test output & summary
• No macros required

Requirements

• C++20
• [For CMake build] CMake 3.22 or newer

Usage

Include stest/test_case.hpp to define test cases, and stest/assert.hpp for assertions.
Or just include stest/stest.hpp to get both.

Example my_unit_tests.cpp:

#include <stest/stest.hpp>

stest::test_block my_tests = [] {           // Introduces a block scope.
    stest::test_case("FooTest") = [] {      // Declares a test case.
        stest::test_assert(foo(3) == 9);    // Ensures an expression is true.
    };
};

test_block allows us to enter a block scope at namespace scope.

test_case(name) = body declares a test case, taking a std::string for the name and any callable for the test case body.

test_assert(expression) asserts that expression is true.

Other assertions available are:

• test_assert_throws<E>(callable) - asserts callable throws E.
• fail_test() - immediately fails the test.

Macro-ful (not recommended)

As an alternative, if you really really want to use macros in exchange for even "simpler" code:

#include <stest/stest.hpp>
#include <stest/macros.hpp>

// No test_block required.
STEST_CASE("FooTest") = [] {
    stest::test_assert(foo(3) == 9);
};

Importing

There are a few methods of importing SimpleTest, depending on your desired build process.

CMake - find_package()

The recommended method is by installing and using find_package(), which will handle finding SimpleTest and checking version compatibility for you.

First, use CMake to install SimpleTest. Navigate to the SimpleTest repo directory, then:

mkdir build
cd build
cmake ..
# Admin/root privileges may be required for this step.
cmake --install .

This installs the SimpleTest source code and exported CMake targets to your system (e.g. on Windows: C:/Program Files/SimpleTest, on Linux: /usr/local).

(A custom install location can be specified with the --prefix install option, and then pointing CMake to that location via SimpleTest_ROOT or CMAKE_PREFIX_PATH.)

Then in your project's CMakeLists.txt:

find_package(SimpleTest 1.0.0 REQUIRED)

add_executable(MyUnitTest my_unit_tests.cpp)
target_link_libraries(MyUnitTest PRIVATE SimpleTest::SimpleTest)

SimpleTest will inject a main() function into the MyUnitTest executable that will invoke all the test cases defined in my_unit_tests.cpp.
If you don't want a main() injected, link to SimpleTest::SimpleTestLib instead.

CMake - add_subdirectory()

add_subdirectory(path/to/SimpleTest)

Targets will be available without the SimpleTest:: namespace.

This is not recommended, especially for library projects, as there is no protection against duplicate imports or incompatible versions.

Manual

Add path/to/SimpleTest/include to your include directories.

If you want a main() to be generated for you, compile and link path/to/SimpleTest/src/stest/main.cpp.

Tests

Yes, even the testing framework has tests! (Otherwise how could you trust your test results?)
The test code is contained in test/ and the CMake target is SimpleTestTest. The target will only be built if the CMake variable SIMPLETEST_BUILD_TEST is set to ON.