[Boost].UT

Overview

• No dependencies (C++17*/C++20, Tested Compilers: GCC-9+, Clang-9.0+, MSVC-2019+*)

• Single header/module (boost/ut.hpp)

• Macro-free (✔️)

• Features (Assertions, Suites, Tests, Sections, BDD, Matchers, Logging, ...)

• (*) Limitations may apply

• [Boost].UT is not an official Boost library

Hello World - https://godbolt.org/z/Y43mXz

// #include <boost/ut.hpp> // Single header
//  import   boost.ut;     // Single module (C++20)

int main() {

  "hello world"_test = [] {
    expect(true);
  };

}

$CXX $CXXFLAGS hello_world.cpp -o hello_world

./hello_world -> All tests passed (1 asserts in 1 tests)

Assertions - https://godbolt.org/z/jaFK8w

expect(1_i == 2);                       // UDL syntax  -> assertions.cpp:1:FAILED [1 == 2]

expect(that % 1 == 2);                  // Matchers syntax  -> assertions.cpp:1:FAILED [1 == 2]

expect(2 == 1_i) << "should equal?";  -> assertions.cpp:1:FAILED [2 == 1] should equal?

 std::vector v{1l, 2l, 3l};
!expect(4_ul == std::size(v));          // Fatal assertion
 expect(v[3] == 4_l);                   // Not executed
  -> assertions.cpp:2:FAILED [4 == 3]

expect(41.10_d == 42.101 and "a" == "b"sv);  -> assertions.cpp:1:FAILED [42.1 == 42.101 and a == b]

Sections - https://godbolt.org/z/y9m5vF

"[vector]"_test = [] {

  std::vector<int> v(5);
  !expect(5_ul == std::size(v));

  should("resize bigger") = [=] {
    v.resize(10);
    expect(10_ul == std::size(v));
  };

  !expect(5_ul == std::size(v));

  should("resize smaller") = [=] {
    v.resize(0);
    expect(0_ul == std::size(v));
  };

};

Behavior Driven Development (BDD) - https://godbolt.org/z/ps9_EQ

"[vector]"_test = [] {

  given("I have a vector") = [] {
    std::vector<int> v(5);
    !expect(5_ul == std::size(v));

    when("I resize bigger") = [=] {
      v.resize(10);

      then("The size should increase") = [=] {
        expect(10_ul == std::size(v));
      };

    };

  };

};

Parameterized - https://godbolt.org/z/6FHtpq

"args"_test = [](const auto& arg) {
  expect(arg > 0_i) << "all values greater than 0";
}

| std::vector{1, 2, 3}; -> All tests passed (3 asserts in 3 tests)

"args and types"_test =
  []<class TArg>(const TArg& arg) {
    expect(std::is_integral_v<TArg>);
    expect(type<TArg> == type<int> or type<TArg> == type<bool>);
  }

| std::tuple{true, 42}; -> All tests passed (4 asserts in 2 tests)

Suites - https://godbolt.org/z/F3xJcJ

suite errors = [] {

  "exception"_test = [] { 
    expect(throws([] { throw 0; })) << "throws any exception";
  };

  "failure"_test = [] {
    expect(aborts([] { assert(false); }));
  };

};

int main() { } -> All tests passed (2 asserts in 2 tests)

Benchmarks - https://github.com/cpp-testing/ut-benchmark

Suite+Assert+STL / 10'000 tests, 20'000 asserts, 100 cpp files

Benchmarks - C++20 Modules - https://github.com/cpp-testing/ut-benchmark

Suite+Assert+STL / 10'000 tests, 20'000 asserts, 100 cpp files

[Boost].UT - https://github.com/boost-experimental/ut

"If you liked it then you "should have put a"_test on it", Beyonce rule

kris@jusiak.net | @krisjusiak | linkedin.com/in/kris-jusiak