Checking if vector re-allocation invoke the copy constructor of each element

main.cpp

#include <iostream>
#include <vector>

class Item {
	private:
		char identifier;

	public:
		Item(char identifier) : identifier(identifier) {
			std::cout << "Item's " << identifier << " constructor called" << std::endl;
		}

		Item(const Item &src) : identifier(src.identifier) {
			std::cout << "Item's " << identifier << " copy constructor called" << std::endl;
		}

		~Item(void) {
			std::cout << "Item's " << identifier << " destructor called" << std::endl;
		}

		Item& operator=(const Item &src) {
			identifier = src.identifier;
			std::cout << "Item's " << src.identifier << " assignation called" << std::endl;
			return *this;
		}
};

int main(void) {
	std::vector<Item> items;

	std::cout << "push_back" << std::endl;
	items.push_back(Item('a'));

	std::cout << "push_back" << std::endl;
	items.push_back(Item('b'));

	std::cout << "push_back" << std::endl;
	items.push_back(Item('c'));

	std::cout << "reserve" << std::endl;
	items.reserve(50);

	std::cout << "push_back" << std::endl;
	items.push_back(Item('d'));

	std::cout << "end" << std::endl;
}

output.sh-session

$ g++ -std=c++98 -o test main.cpp && ./test
push_back
Item's a constructor called
Item's a copy constructor called
Item's a destructor called
push_back
Item's b constructor called
Item's b copy constructor called
Item's a copy constructor called
Item's a destructor called
Item's b destructor called
push_back
Item's c constructor called
Item's c copy constructor called
Item's a copy constructor called
Item's b copy constructor called
Item's a destructor called
Item's b destructor called
Item's c destructor called
reserve
Item's a copy constructor called
Item's b copy constructor called
Item's c copy constructor called
Item's a destructor called
Item's b destructor called
Item's c destructor called
push_back
Item's d constructor called
Item's d copy constructor called
Item's d destructor called
end
Item's a destructor called
Item's b destructor called
Item's c destructor called
Item's d destructor called