examples/subcases_and_bdd/main.cpp

#define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
#include "doctest.h"

#include <iostream>
#include <vector>
using namespace std;

TEST_CASE("lots of nested subcases") {
    cout << endl << "root" << endl;
    SUBCASE("") {
        cout << "1" << endl;
        SUBCASE("") { cout << "1.1" << endl; }
    }
    SUBCASE("") {   
        cout << "2" << endl;
        SUBCASE("") { cout << "2.1" << endl; }
        SUBCASE("") {
            cout << "2.2" << endl;
            SUBCASE("") {
                cout << "2.2.1" << endl;
                SUBCASE("") { cout << "2.2.1.1" << endl; }
                SUBCASE("") { cout << "2.2.1.2" << endl; }
            }
        }
        SUBCASE("") { cout << "2.3" << endl; }
        SUBCASE("") { cout << "2.4" << endl; }
    }
}

SCENARIO("vectors can be sized and resized") {
    GIVEN("A vector with some items") {
        std::vector<int> v(5);

        REQUIRE(v.size() == 5u);
        REQUIRE(v.capacity() >= 5u);

        WHEN("the size is increased") {
            v.resize(10u);

            THEN("the size and capacity change") {
                CHECK(v.size() == 20u);
                CHECK(v.capacity() >= 10u);
            }
        }
        WHEN("the size is reduced") {
            v.resize(0);

            THEN("the size changes but not capacity") {
                CHECK(v.size() == 0u);
                CHECK(v.capacity() >= 5u);
            }
        }
        WHEN("more capacity is reserved") {
            v.reserve(10);

            THEN("the capacity changes but not the size") {
                CHECK(v.size() == 5u);
                CHECK(v.capacity() >= 10u);
            }
        }
        WHEN("less capacity is reserved") {
            v.reserve(0);

            THEN("neither size nor capacity are changed") {
                CHECK(v.size() == 10u);
                CHECK(v.capacity() >= 5u);
            }
        }
    }
}